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1
Johnson, Jack Buckland Jr. "Evaluating the Importance of Strength, Power, and Performance Tests in an NCAA Division I Football Program." Diss., Virginia Tech, 2001. http://hdl.handle.net/10919/29933.
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Strength and conditioning professionals spend a great deal of time and effort trying to improve athletic performance. Even as coaches evaluate each athlete by using the results of a vast battery of tests, there has been considerable speculation and discussion about the physical attributes of Division I football players and their playing status. The purpose of this study was to determine what influence strength, power, and performance tests scores have on an individual's playing status.
The Skill group results indicate that power is the most important factor differentiating between starters and non-starters. Simultaneously, the Combo group results indicate that speed is the most important factor differentiating between starters and non-starters. Also, the L.O.S. group results indicate that bodyweight is the most important factor differentiating between starters and non-starters.Ph. D.
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Englund, Jon. "Structural strength of work boatsand high speed crafts with floatingframes." Thesis, KTH, Marina system, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-121320.
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This thesis investigates the usage of floating frames in boats. A floating frame is a transverse frame fittedto the longitudinal stiffener flanges without contact with the shell plating, as opposed to the traditionalfixed frame which is welded to the shell plating with the stiffeners most commonly fitted through cut outsin the frame.To study the floating frame structure in a bigger perspective a finite element analysis is performed on amid ship compartment of an existing 60 m high speed catamaran ferry. The analysis is performed on amodel with scantlings as the original craft but with introduced floating frames. Stresses are analysed withrespect to maximum allowable stress as given in the DNV-rules for HAZ.High stresses are found in the bottom of the frames due to the reduced bending stiffness without effectiveflange from the shell plating. A large deformation in the shell plating relative the transverse frames isfound, creating high stresses in the stiffener webs. This deformation is induced by a large verticaldeformation of the frames.It is concluded that the transverse frames requires an increased stiffness to achieve acceptable stress levels.Possible solutions to increase stiffness are discussed, further studies are required to achieve an acceptablestructure.A design criterion for stiffeners in floating frame constructions is evaluated. The criterion considers theinteraction between a concentrated contact force and a bending moment with the purpose of simplifyingthe design process of stiffeners. The criterion is a combination of design methods from DNV HSLC andEurocode 9.The design criterion is found to give conservative results, although not unreasonably conservative. Thecriterion is suitable for the design of smaller work boats where the scantlings traditionally are not veryoptimized.
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Tchikanda, Serge William. "Modeling for high-speed high-strength precision optical fiber drawing." Diss., Georgia Institute of Technology, 2001. http://hdl.handle.net/1853/20051.
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Flyen, Ane Horten. "The Association between Gait Speed and Lower Extremity Strength in Elderly." Thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for bevegelsesvitenskap, 2013. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-21631.
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Background: Gait speed has been strongly associated with functioning and also found to be a global index of functioning in elderly. Similarly, low general muscle strength has been associated with physical inactivity and functional impairment. Aim: The aim of this study was to investigate whether there is an association between gait speed and lower extremity strength in elderly. Design: This was a cross-sectional study. Methods: 489 community-dwelling women and men (71.5 ± 5 yrs) filled out a questionnaire for background information, and were tested for gait speed and lower extremity strength. Gait speed was measured while participants walked in their preferred and fast gait speed on an electronic GaitRite walking mat. Lower extremity strength was tested with the Sit-to-stand performance test and leg press. Results: Significant, low to strong, positive associations were found between both gait speed levels and the Sit-to-stand parameters in both genders (p < 0.0005). Fast gait speed was strongly associated with peak V in both women and men (p < 0.0005). There was found low to moderate associations between gait in both speed levels and leg press parameters in both genders (p < 0.0005). Strong associations were also found between gait speed and step length in both speed levels (p <0.0005) and between peak force (F) and peak rate of force development (RFD) in leg press in both genders (p < 0.0005). Conclusion: Gait speed is associated with lower extremity strength in elderly, with increase in gait speed associated with increase in lower extremity strength. When gait speed increases, step length and cadence increases as well. Men walked faster and had stronger lower extremity strength than women. Future studies should investigate the direction of the association between gait speed and lower extremity strength through a prospective study, to see whether it is possible to maintain good function in gait by conduct lower extremity strength training or if it is more effective to focus on gait speed to maintain good lower extremity strength. Key Words: Gait speed, step length, cadence, lower extremity strength, functional strength, isometric strength, leg strength, leg press, sit-to-stand test and elderly.
5
Pethan, Scott M. "Effects of training in Strength Shoes [symbol for trademark] on speed, jumping ability, and calf girth /." Connect to online version, 1993. http://minds.wisconsin.edu/handle/1793/38911.
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Hinojosa, Richard. "The Interrelationships of Strength, Speed, Power and Anthropometric Measures in College Aged Women." Thesis, North Texas State University, 1985. https://digital.library.unt.edu/ark:/67531/metadc500785/.
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The purpose of the investigation was to determine the interrelationships of strength, speed, power and anthropometric measures in women. Sixty females ranging in ages from 18 to 25 volunteered as subjects. Subjects were measured for strength on the bench press, leg extension and leg curl, power vertical jump, speed--a 40 yard dash, body weight (BW) and fat weight (FW) using a scale and skinfold tests. The correlations for strength and power (.35 to .53), strength and speed (-.37 to -.56) and speed and power (-.45) were significant (p < .01). Partial correlations with (BW) and (FW) held constant were also significant, but were not significantly greater than their zero-order correlations.
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Faccioni, Adrian, and n/a. "Relationships between selected speed strength performance tests and temporal variables of maximal running velocity." University of Canberra. Human & Biomedical Sciences, 1995. http://erl.canberra.edu.au./public/adt-AUC20060707.160114.
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The relationships between selected sprint specific bounding exercises and sprint
performance were analysed using fourteen sprint athletes (7 elite performers, 7 sub-elite
performers). Subjects were required to perform sprints over 60m, Counter Movement
Jumps with and without loading (20kg), High Speed Alternate Leg Bounding over 30m
and High Speed Single Leg Hopping over 20m. All athletes were subject to
anthropometric measurement (Height, Weight and Leg Length). Of all variables
measured, the Elite group were significantly better (p<0.001) in Counter Movement
Jump, Time to 60m, Time from 30m to 60m and in their Maximal Running Velocity.
Linear regressions were carried out on all variables that correlated with Time to 30m
(Acceleration Phase) and Maximal Running Velocity at both the pO.OOl and p<0.01
level of significance. This allowed several prediction tables to be compiled that had
performance measures (sprints and jumps) that could be used as testing measures for
sprint athletes to determine their Acceleration Phase and Maximal Running Velocity. A
stepwise multiple regression demonstrated that Time to 60m was the best predictor of
Maximal Running Velocity. Time to 60m, Leg length, High Speed Alternate Leg
Bounding and Sprint Stride Rate were the best predictors of the Acceleration Phase. A
Stepwise cross-validation linear discriminant function analysis was used to determine the
best predictors from both sprint and jump measures that would distinguish an athlete as
an elite or sub-elite performer. From sprint variables, Time to 60m and Time to 30m were
the two variables that best placed a sprint subject in either the Elite or Sub-elite group.
From the bounding variables, Counter Movement Jump and the Ground Contact Time of
the High Speed Alternate Leg Bounding were the two variables that best placed a sprint
subject in either the Elite or Sub-elite group. The present study suggests that Time to 60m
is the best predictor of Maximal Running Velocity and Acceleration Phase. Counter
Movement Jumping and High speed Alternate Leg Bounding are also useful tools in
developing and testing elite sprint athlete performance.
8
Shelton, P. W. "The influence of temperature on the strength, stiffness and toughness of high-speed steels." Thesis, University of Bradford, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.371533.
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Miller, James. "Changes in Sprint Kinematics Between Phase Potentiation and Linear PRogressive Models of Resistance Training." Digital Commons @ East Tennessee State University, 2017. https://dc.etsu.edu/etd/3309.
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Fifteen well-trained males, mid-thigh pull peak force (IPF 4403.61 ± 664.69N) and isometric peak force allometrically scaled (IPFa 226.04 ± 25.81) were assigned to two groups: repetition maximum training (RM) and relative intensity training (RI) for a twelve-week training intervention. The main effect of time showed a statistically significant difference in mean sprint performance and IPFa at the different time points (p < 0.001). There was a larger magnitude of within-subject effect with respect to sprint performance pre – post with the RI group (ES = 1.06, 7.19%) as compared to the RM group (ES = 0.567, 4.23%, p < 0.001), as well as a larger magnitude of within-subject effect with respect to IPFa pre – post with the RI group (ES = 0.426, 7.51%) as compared to the RM group (ES = 0.270, 13.29%). Furthermore, there was a non-statistically significant, moderate between-group difference in the change in IPFa from pre-post in favor of the RI group (ES=.75), and a large between-group difference in the change in sprint performance pre-post in favor of the RI group (ES=1.50). Results lead investigators to suggest the utilization of RI training tactics for the development of sprint performance when minimal sprint skill training is available.
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Heron, Gary D. "SPEED AND AGILITY TRAINING THE MUSTANG WAY: THE DEVELOPMENT OF AN INSTRUCTIONAL DVD FOR CAL POLY ATHLETES' SUMMER TRAINING." DigitalCommons@CalPoly, 2013. https://digitalcommons.calpoly.edu/theses/953.
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SPEED AND AGILITY TRAINING THE MUSTANG WAY:
THE DEVELOPMENT OF AN INSTRUCTIONAL DVD FOR CAL POLY ATHLETES’ SUMMER TRAINING
Gary Douglas Heron
The purpose of this project was to create an instructional DVD of speed and agility training for Cal Poly student-athletes. The DVD is for athletes’ use when they are away from campus during summer break and contains information about the same drills and information the strength and conditioning coaches provided while athletes were on campus. The project was filmed and edited by the graduate assistant strength and conditioning coach for Cal Poly intercollegiate athletics. The DVD contains 74 drills that encompass speed techniques, acceleration techniques, plyometrics, footwork, and change of direction. Recommendations for further empirical research in the area of speed and agility training are provided.
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LI, Jr-Hung. "INFRARED BRAZING OF LOW CARBON SPEED WITH COPPER FILLER." University of Cincinnati / OhioLINK, 2001. http://rave.ohiolink.edu/etdc/view?acc_num=ucin990736063.
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Magrum, Eric D. "Outcomes of an Integrated Approach to Speed and Strength Training with an Elite-Level Sprinter." Digital Commons @ East Tennessee State University, 2017. https://dc.etsu.edu/etd/3187.
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The purpose of this study was to observe changes in sprint velocity, ground contact time, and peak force demonstrated by a competitive sprinter following an integrated approach to speed development and strength training. As part of an ongoing monitoring procedure the participant completed 20m sprint testing through an optical measurement system and isometric-strength testing before and after each phase of training. Sprint velocity, ground contact time and peak force were analysed using Tau-U, smallest worthwhile and percent change statistics. Results indicate sprinting velocity statistically improved while changes in peak force were practically significant and ground contact time remained trivial throughout the investigation. Results lead investigators to suggest the implementation of a periodized approach merging technical skill and the development of physical abilities. The integrated approach provided a transfer of training effect and may have been the primary source of sprint enrichment.
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Zhang, Lihe. "Impact resistance of high strength fiber reinforced concrete." Thesis, University of British Columbia, 2008. http://hdl.handle.net/2429/705.
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Concrete structures may be subjected to dynamic loading during their service life. Understanding the dynamic properties of concrete structures is becoming critical because of the increased concern about the dynamic loading of both civilian and military structures, and especially, the recent increase in terrorist attacks on structures. Fiber reinforced concrete (FRC) is known to exhibit superior performance in its post-peak energy absorption capacity, (i.e., toughness) under flexural and tensile loading. However, the behavior of fiber reinforced concrete under compressive impact has not previously been investigated. In the present research, the response of fiber reinforced concrete was investigated over the full strain rate regime, from static loading to high strain rate loading, and finally to impact loading. The compressive toughness of FRC under static loading was studied using an existing Japanese standard (JSCE SF-5). Then, a test method for FRC under compressive impact loading was developed, involving the use of a high speed video camera system to measure the deformation of FRC cylinders under compressive impact.
The strain rate sensitivity of FRC in both flexure and compression was also fully investigated. FRC was found to have higher strengths under impact loading (both flexural and compressive) than under static loading. The compressive toughness under impact loading increased due to the high peak load and the high strain capacity. FRC under flexural impact loading showed a greater strength improvement than under static flexure. FRC displays a much higher Dynamic Improvement Factor (DIF) under flexural impact than under compressive impact. It gave an overall higher performance under impact than under static loading. It also exhibited a higher strain rate sensitivity than plain concrete in both compression and flexure.
Damage analysis, in terms of loss of strain energy, was carried out based on damage mechanics principles. Damage was found to increase with increasing strain rate. A new constitutive model was proposed to account for the relationship between DIF (Comp) and strain rate and the data derived from the model were found to be consistent with the experimental results.
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Hollins, Jana. "The Relationships of Physiological and Strength Variables to Run Performances." Digital Commons @ East Tennessee State University, 2015. https://dc.etsu.edu/etd/2552.
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Monitoring progress of athletes is an essential component of the training process. Collegiate distance running coaches often use field tests to assess progress because of a lack of time and resources to do laboratory testing. The purpose of this dissertation was to examine the relationships between physiological and strength variables measured in a laboratory and field testing measures in collegiate distance runners. Collegiate distance runners completed a series of tests in the Sport Science laboratory at East Tennessee State University to obtain physiological and strength parameters, such as V̇ O2max and vertical jump height. The athletes then completed one of two field tests (either a 3 km time trial or a 3 minute all out run test). There were strong correlations between the laboratory measures and the field test performances. These results indicate that strength is an important factor in run performance. Also, a 3 km time trial and a 3 minute all out run test are suitable for athlete monitoring.
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Mong, Lars Johan. "Structural strength of work boats and high speed crafts with pre-fabricated, floating panels in aluminum." Thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for marin teknikk, 2011. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-15478.
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This thesis evaluates some relevant aspects related to structural integrity for work boats and high speed vessels with floating frames. This structural design is expected to significantly reduce the building cost, but it is also expected to reduce the structural strength of the vessel. A model of a modified version of the JumboCat 60 (JC60) with floating frames is used as a recurring example in the calculations. As of date, the use of floating frames in not acknowledge by the classification societies. The traditional version of the JC60 is however classified according to the DNV HSLC rules, and it is shown that the scantlings for the floating frame version exceeds the minimum requirements in the rules. Finite element models of the traditional and the floating frame version of the JC60 has been developed. These has been analysed for three different load conditions as defined in the DNV Classification Notes 30.8, namely the symmetric bottom slamming, the transverse split force, and the torsional/pitch-connecting moment load condition. These load conditions are assumed to be the most critical. From the finite element analyses, it is seen that the structural response for both models is quite similar. Only the transverse split force load condition analyses showed stresses exceeding the allowable stress levels given in the DNV HSLC rules. However, the results indicated that the hull beam of the traditional model was slightly stiffer, so it is suggested that the plate thickness for the shell plating in the floating frame version is increased at some critical regions. An increase of the longitudinal stiffener shear area is also seen necessary to reduce high shear stresses at critical areas for the floating frame version. A fatigue assessment of the longitudinal stiffener-transverse floating frame connection has been performed. Three different locations were identified as potentially critical in terms of excessive fatigue damage. Those were located at the middle of the stiffener flange at the weld toe, at the edge of the stiffener flange at the weld toe, and at the edge of the frame bottom flange. The long term distribution of stresses was approximated by a twoparameter Weibull distribution. The shape factor was set to 0.81 and the number of load cycles for 20 years of service was set to 100 million. The maximum stress range in the load history was assumed to occur for symmetric bottom slamming. Four finite element models of the structural detail were developed and analysed for determination of the maximum stress range. It was found by Miner summation that none of the locations considered would experience a critical fatigue failure for 20 years of service.
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Ervik, Toralf. "Structural Strength of Work Boats and High Speed Crafts with Pre-fabricated, Floating Panels in Aluminium." Thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for marin teknikk, 2010. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-11471.
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Aluminium is a material commonly used for smaller boats and high speed crafts due to its low weight. Traditionally the hull construction is performed in a similar manner as that of steel ships, with longitudinal stiffeners fitted through cut-outs in the transverse web frames and welded to the shell plating. This requires much fitting and welding, making the production of hulls a slow and expensive task due to the manual labour needed. An alternative method for construction of aluminium hulls is to extrude panels consisting of both the shell plating and stiffener. These pre-fabricated panels are then welded directly to the transverse frames, thus reducing the manual labour related to hull production significantly. This thesis continues the work previously performed by Jon Englund on floating panels. He found that the stresses will increase significantly in a floating frame structure compared to that of a traditional, fixed structure. It was discovered that the main challenge of a floating frame structure is out-of-plane bending stresses occurring in the stiffeners webs due to frame deflections. By use of finite element analyses and analytical calculations, a compartment of the JumboCat 60 is analysed, and proposals for achieving acceptable stresses are given. The stiffener stresses mentioned above are found to be drastically reduced by increasing the bending- and axial stiffness of the transverse web frames. Local stress concentrations are found in the intersection between stiffener and web frame. Nonlinear finite element analyses show that substantial strain-hardening can be achieved in the stiffeners webs through cyclic loading. The loss of strength due to welding may thus be partly recovered.
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Karki, Utsab. "Experimental and Numerical Study of High-Speed Friction Stir Spot Welding of Advanced High-Strength Steel." BYU ScholarsArchive, 2015. https://scholarsarchive.byu.edu/etd/5521.
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With the desire to lighten the frame while keeping or increasing the strength, Advanced High-Strength Steels (AHSS) have been developed for use in the automotive industry. AHSS meet many vehicle functional requirements because of their excellent strength and acceptable ductility. But joining AHSS is a challenge, because weldability is lower than that of mild steels. Friction stir spot welding (FSSW) is a solid state joining process that can provide a solution to the weldability issues in AHSS, but FSSW has not been studied in great detail for this application. In this work, Si3N4 tools were used for FSSW experiments on DP 980 steel with 1.2mm thickness. Joint strength was measured by lap shear tension testing, while thermocouples were used for the temperature measurements. A finite element model was developed in order to predict material flow and temperatures associated with FSSW. Since a 3D model of the process is very time consuming, a novel 2D model was developed for this study. An updated Lagrangian scheme was employed to predict the flow of sheet material, subjected to the boundary conditions of the fixed backing plate and descending rotating tool. Heat generation by friction was computed by including the rotational velocity component from the tool in the thermal boundary conditions. Material flow was calculated from a velocity field while an isotropic, viscoplastic Norton-Hoff law was used to compute the material flow stress as a function of temperature, strain and strain rate. Shear stress at the tool/sheet interface was computed using the viscoplastic friction law. The model predicted welding temperatures to within 4% of the experiments. The welding loads were significantly over predicted. Comparison with a 3D model of FSSW showed that frictional heating and the proportion of total heat generated by friction were similar. The position of the joint interface was reasonably well predicted compared to experiment.
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Ericsson, Mats. "Fatigue Strength of Friction Stir Welded Joints in Aluminium." Doctoral thesis, Stockholm, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-160.
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Omae, Kenji. "Gait speed and overactive bladder in the healthy community-dwelling super elderly-The Sukagawa Study." Kyoto University, 2020. http://hdl.handle.net/2433/245838.
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Bellon, Christopher. "The Relationship Between Strength, Power, and Sprint Acceleration in Division I Men’s Soccer Players." Digital Commons @ East Tennessee State University, 2016. https://dc.etsu.edu/etd/3087.
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The purposes of this dissertation were three-fold. The first was to identify the approximate distances characterizing early-, mid-, and late-acceleration in a population of Division I men’s collegiate soccer players. The secondary purpose was to investigate the relationships between various strength-power variables and key sprint characteristics during early-, mid-, and late-acceleration in a population of Division I men’s soccer players. The final purpose of this dissertation was to compare the spatiotemporal characteristics of “strong” versus “weak” and “more powerful” versus “less powerful” Division I men’s soccer players during early-, mid-, and late- acceleration. The following are the major findings of this dissertation. The early-, mid-, and late-acceleration zones within this sport population coincide with distances of approximately 0-2.5, 2.5-6, and 6-12m, respectively. Peak power (PP) and rate of force development (RFD) at 90ms appear to be strongly related to shorter ground contact times in each of these zones, while PP and RFD at 200 and 250ms showed strong relationships with step frequency during mid-acceleration. Not surprisingly, athletes who were characterized as “strong” or demonstrated “higher power outputs” appeared to achieve greater sprint velocity by expressing higher step frequency, particularly during mid-acceleration, as well as abbreviated ground contact times across each sub-section of acceleration. These results support the importance of developing high levels of maximal strength, PP, and RFD to enhance sprint acceleration. Additionally, these findings may also be used to strategically integrate speed development and resistance training practices into the annual training plan. The amalgamation of these training variables may allow practitioners to better manage fatigue and elicit desired performance adaptations at the appropriate times of the training year.
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Bramley, Wesley Joel. "The relationship between strength, power and speed measures and playing ability in premier level competition rugby forwards." Queensland University of Technology, 2006. http://eprints.qut.edu.au/16252/.
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Physical tasks such as scrummaging, rucking and mauling are highly specific to rugby and also place unique physiological demands on the different playing positions within the forwards. Traditionally, the recruitment and development of talented rugby union players has focused on the assessment of motor skills and game intelligence aspects of performance, with less emphasis placed on the specific physiological requirements of playing positions in rugby. The purpose of this investigation was to measure the position-specific strength, speed and power characteristics of Premier rugby forwards in order (1) to determine whether any differences existed in the physiological characteristics of the different forward playing positions (prop, lock and loose forwards) and (2) to investigate the relationship between these physiological characteristics and coaches evaluations of football playing ability. Twenty-two male Premier level competition rugby forwards, consisting of eight prop forwards, five lock forwards and nine loose-forwards participated in the study. The Grunt 3000, a rugby specific force testing device was utilised to measure the static and dynamic horizontal strength during simulated scrummaging and rucking/mauling movements. Sprint times relating to acceleration ability (0 -10m, 0-20m) and maximum running speed (20 - 40m) were measured during a 40m sprint running test. In addition, force, power and displacement characteristics of a countermovement vertical jump were calculated from trials performed on a force plate. Also, player performance skill and physical capacity scores were determined independently by experienced coaches who assessed them based on their performances during the season. One-way analysis of variance and effect size statistics evaluated differences in the measured variables between forward playing positions and linear regression analysis evaluated the relationship between the coaches' scores of player performance skill and physical capacity and game specific measures of strength speed and power. Since there were no statistical significant differences between forward groups for horizontal force and countermovement jump variables and these analyses lacked statistical power, an effect size statistic was used to establish trends for differences in force and CMJ variables between the groups. There were moderate effect size differences between groups for horizontal impact force with prop and lock forwards producing 17.7% and 12.8% more force than the loose forwards respectively. No clear differences were apparent between forward positional groups for mean dynamic horizontal force and countermovement jump displacement of the centre of gravity. A significant difference (p =0.049) was shown between forward positional groups over the 0-40m sprint distance. Also, moderate effect size differences between pairs of groups were evident in 0-10m, 0-20m, 20-40m sprint times with both loose forwards and lock forwards on average, 6% faster than the prop forwards. A backward linear regression analysis revealed that the single best predictor of coaches' physical capacity and performance skill scores was the 20 - 40m sprint performance, accounting for 28% of the variance in player's physical capacity scores and 29% of the variance in player's performance skill scores. Whole-body horizontal static strength and impact strength in prop forwards and dynamic horizontal strength (relative to body mass) and sprint acceleration ability in loose forwards represent key factors for consideration when selecting forward players to these positions in the Premier rugby competition. The vertical jumping ability of all forward positional groups needs to be confirmed in a future study utilising a line-out specific countermovement jump test (free use of arm swing and line-out lifters in the jump) on a force plate. Monitoring of performance in rugby forwards should include an acceleration sprint test (0-10m) as this is specific to the sprinting patterns of forward players during a game, and maximum sprinting speed test (20-40m) as this test has the ability to discriminate between skilled and less-skilled rugby union forwards.
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Senn, Daniel LeRoy. "Short-term Training Effects of Dynamic Warm Up Volume on Speed, Power, and Agility." Thesis, North Dakota State University, 2011. https://hdl.handle.net/10365/29320.
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This study examined the short-term training effects of two volumes of a dynamic warm up
performed 4 days per week over a 3 1/2-week period. A total of 25 Division III wrestlers
volunteered for the study. Three participants either dropped out or were unable to attend
post-testing, resulting in 22 total participants completing the study. Groups were divided
into control, low volume, and high volume groups. All participants completed pre and poststudy
performance tests including the standing long jump, proagility, start-stop-cut, and 30-
meter sprint. The low and high volume training groups each performed the same dynamic
warm up prior to each pre-season captain's practice. The control group did not participate
in an organized warm up. The low volume group performed one set of each warm up
exercise, and the high volume group performing two sets of each warm up exercise. Data
analysis indicated significant increases in performance for the standing long jump (p =
.011) and start-stop-cut (p = .000) measures among the entire sample population. However,
there was no significant difference between the groups in these measures. No significant
results were found either for the sample as a whole or between groups for the proagility and
30-meter measures. The increased performance of all groups, including the control group,
fails to provide evidence for the effectiveness of training with either warm up volume.
Further research is needed to address limitations of this study to determine effectiveness of
various warm up volumes.
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Eastman, Carie Suzanne. "Effect of High-Speed Treadmill Training with a Body Weight Support System in a Sport Acceleration Program." BYU ScholarsArchive, 2011. https://scholarsarchive.byu.edu/etd/2739.
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Introduction: Maximum running acceleration essential components in many sports. The identification of specific training protocols to maximize sprint speed would be useful knowledge for soccer coaches and players.
Purpose: The purpose of this study was to determine the effect of a high-speed treadmill with the use of a body-weight support system in a 6-week sport acceleration program on: 40-yard sprint time, maximal isometric knee flexor and extensor strength.
Methods: 32 female soccer players (age 16 ± 1.19 yrs) participated in two treatment groups and one control group. Both treatment groups participated in a 12-session sport acceleration program. The first treatment group utilized a body-weight support system while on a high-speed treadmill; the second group used a standard treadmill with no body weight support system. The control group, NT, did not participate in a sports acceleration program and did not alter their exercise routines outside of the study.
Results: For each variable an Analysis of Covariance (ANCOVA) was performed. 40-yard sprint times for treatment groups were shown to improve significantly as compared to the control group (p = 0.0007 for high-speed treadmill with body-weight support system, p= < 0.0001 for standard treadmill without body-weight support system). Isometric flexor and extensor strengths did not show significant differences between treatment groups and control group. P-values for the high-speed with body-weight support system were (p = 0.53) for flexors and (p = 0.51) for extensors as compared to the control group. P-values for the standard treadmill with no body-weight support system were (p = 0.19) for extensors and (p = 0.0263) for flexors. It is noted that the extensor muscles were nearly significant for the standard treadmill with no body-weight support system.
Discussion: These results can help high school coaches and athletes determine the optimal treadmill training regime. The current study shows that a high-speed treadmill with body-weight support system is just as beneficial as standard treadmill training.
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Junior, Joel Moraes Santos. "Relação entre a força propulsora e a velocidade nos quatro estilos competitivos da natação." Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/39/39134/tde-01042013-155638/.
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Embora muitos estudos tenham investigado a contribuição da força propulsora na velocidade de nadadores, a maioria das pesquisas se restringiu ao estilo crawl e no nado como um todo. Sendo assim, o objetivo do presente estudo foi mensurar e comparar a força propulsora e o desempenho de velocidade nos quatro estilos competitivos e verificar a relação entre elas durante o nado completo, o nado somente de pernas e o nado somente de braços em nadadores competitivos. Participaram do estudo 37 nadadores do sexo masculino com experiência competitiva de no mínimo dois anos, com idade entre 15 e 19 anos. A amostra foi dividida pelos estilos borboleta (n=9), costas (n=7), peito (n=9) e crawl (n=12). Foram medida as variáveis de força propulsora (VFP) no nado atado (NA) nas seguintes situações; força propulsora máxima de nado em 10 segundos (FPM10), força propulsora máxima de pernas em 10 segundos (FPMp), força propulsora máxima de braços em 10 segundos (FPMb), força propulsora máxima de nado em 25 segundos (FPM25) força propulsora média de nado em 25 segundos (FPm25). Também foi mensurada a velocidade nas metragens de 15 e 50 metros (V15 e V50). Cada nadador realizou os testes de força e velocidade nos principais estilos de competição. Os resultados demonstraram correlações entre as VFP com a velocidade para os quatro estilos competitivos no nado completo (entre r=0,62 e 0,97), na força propulsora de pernas nos estilos costas e crawl (r=, 0,77, 0,73 e 0,72) e para a força propulsora de braços no estilo crawl (r=0,73). O estilo peito se correlacionou de maneira moderada negativamente (r=, -0,69, -0,75, -0,76 e -0,77) com a FPM10, FPM25, FPM25 e FPm25. Conclui-se que a força propulsiva apresentou relação com a velocidade nos quatro estilos competitivos e que tal relação é melhor no nado completo quando comparada aos membros inferiores e superioresAlthough many studies have investigated the contribution of propulsive force in speed of swimmers, most studies has been restricted to crawl and complete swimming. So, the objective of this study was to measure and compare the propulsive force and speed performance on all four competitive strokes and the relation between them during complete swimming, propulsive force of the legs and of the arms. The study included 37 male swimmers competitive with at least two years, with ages between 15 and 19 years old. The sample was divided by styles butterfly (n = 9), back (n = 7), breast (n = 9) and crawl (n = 12). We analyze the propulsive force variables (VFP) in tethered swimming (NA) in situations: maximum propulsive force of swimming in 10 seconds (FPM10) maximum propulsive force of legs in 10 seconds (FPMp), maximum propulsive force of arms in 10 seconds (FPMb), maximum propulsive force of swimming in 25 seconds (FPM25) mean propulsive force of swimming in 25 seconds (FPm25). Also the speed was measured at distances of 15 and 50 meters (V15 and V50). Each swimmer performed the tests of strength and speed in the main styles of competition. The results showed correlations between VFP with speed for the four competitive swimming in complete swimming (between r = 0.62 and 0.97), in the propulsive force of legs in the back and crawl styles (r = 0.77, 0.73 and 0.72) and the propulsive force of arms in the crawl (r = 0.73). The breaststroke showed moderate negative correlation (r = -0.69, -0.75, -0.76 and -0.77) with FPM10, FPM25, and FPM25 FPm25. It is concluded that the propulsive force was related to the speed in four competitive and that this relationship is better in comparison to the complete swimming upper and lower limbs
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Schwicht, Daniel Ethan. "Large-Scale Strength Testing of High-Speed Railway Bridge Embankments: Effects of Cement Treatment and Skew Under Passive Loading." BYU ScholarsArchive, 2018. https://scholarsarchive.byu.edu/etd/7346.
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To investigate the passive force-displacement relationships provided by a transitional zoned backfill consisting of cement treated aggregate (CTA) and compacted gravel, a series of full-scale lateral abutment load tests were performed. The transitional zoned backfill was designed to minimize differential settlement adjacent to bridge abutments for the California High Speed Rail project. Tests were performed with a 2-D or plane strain backfill geometry to simulate a wide abutment. To investigate the effect of skew angle on the passive force, lateral abutment load tests were also performed with a simulated abutment with skew angles of 30º and 45º. The peak passive force developed was about 2.5 times higher than that predicted with the California HSR design method for granular backfill material with a comparable backwall height and width. The displacement required to develop the peak passive force decreased with skew angle and was somewhat less than for conventional granular backfills. Peak passive force developed with displacements of 3 to 1.8% of the wall height, H in comparison to 3 to 5% of H for conventional granular backfills.The skew angle had less effect on the peak passive force for the transitional backfill than for conventional granular backfills. For example, the passive force reduction factor, Rskew, was only 0.83 and 0.51 for the 30º and 45º skew abutments in comparison to 0.51 and 0.37 for conventional granular backfills. Field measurements suggest that the CTA backfill largely moves with the abutment and does not experience significant heave while shear failure and heaving largely occurs in the granular backfill behind the CTA backfill zone.
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Srinivaas, Sujith. "Testing and Analysis of Innovative High-Speed Automotive Fastening System for Multi Materials." The Ohio State University, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=osu1587397193415362.
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Prasitsiriphon, Orawan, and Daniela Weber. "Objective physical measures and their association with subjective functional limitations in a representative study population of older Thais." Springer Nature, 2019. http://dx.doi.org/10.1186/s12877-019-1093-3.
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In this study, we analyzed elderly people in Thailand to identify the validity of suggested cutoff points of physical measures, handgrip strength, usual walking speed, and a composite score of both measures to predict functional limitations. Moreover, we examined whether these physical performance measures are accurate indicators of the investigated health outcomes.
Methods: Using Receiver Operating Characteristics (ROC) analysis, we investigated a sample of 8272 respondents aged 60 to 79 years. All data were based on the 2009 National Health Examination Survey (NHES IV) of Thailand.
Results: For males aged 60 to 69 years, handgrip strength was used as an indicator of functional limitations. The cutoff point for disabilities in the activities of daily living (ADLs) was 29.5 kg, while in other limitations it ranged from 28.7 to 31.3 kg. In contrast, usual walking speed was able to indicate ADL disabilities at 0.7 m per second (m/s). As one might expect, the cutoff points for males aged 70 to 79 years were lower than for males in the 60 to 69 age group. For females, handgrip strength was able to indicate ADL disabilities at 16.5 kg for both the 60 to 69, and 70 to 79 age groups. Likewise, walking speed was indicative of ADL disabilities at 0.6 m/s for both age groups. Interestingly, the composite measure increases the ability to detect ADL disabilities in the younger group but not in the older group. The area under the curve (AUC) of cutoffs measuring the detection power of a diagnostic test was varied, ranging from 0.535 to 0.7386.
Conclusions: The cutoff points of three measures varied according to sex and type of functional limitations. Our findings also showed that physical performance measures were useful for identifying people with an increased risk of functional limitations, particularly for ADL disabilities. However, although the AUC of the cutoffs of other functional limitations were relatively low, they should be considered with caution.
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Berberi, Ilias. "Performance Trade-Offs in Wild White-Footed Mice (Peromyscus Leucopus)." Thesis, Université d'Ottawa / University of Ottawa, 2018. http://hdl.handle.net/10393/38382.
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Various aspects of performance (e.g., sprint speed, grip strength) are thought to be important determinants of the success of animals in natural activities such as foraging, mating, and escaping from predators. However, it is generally known that morphological properties enhancing one type of performance (e.g., speed) can lead to a reduction in another (e.g., strength). Such performance trade-offs have been quantified at the inter-specific level, but evidence at the inter-individual level remains equivocal. To test for the presence of a performance trade-off, I initiated a study on wild white-footed mice (Peromyscus leucopus). In summer 2016, I captured a total of 186 individuals, 87 of which were repeatedly phenotyped for grip strength and sprint speed. A significant positive relationship was found between body mass and grip strength (but not for sprint speed). Individual differences in performance were repeatable through time for both grip strength and sprint speed. Using a bivariate mixed model, I detected a significant negative correlation between grip strength and sprint speed at the among-individual level. By contrast, the within-individual correlation between grip strength and sprint speed tended to be positive, suggesting that some unquantified aspects of the mouse phenotype (e.g., body condition, age) may have a positive effect on both performance traits. Given the relatively low repeatability of grip strength and sprint speed, a failure to properly partition the correlation at the among- and within-individual level generates a counter-intuitive, positive correlation. This study is one the first to detect a performance trade-off at the among-individual level in a wild animal population.
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Frennessen, Sebastian, and Jens Ericsson. "Sambandet mellan skotthastighet, handgreppstyrka samt skridskohastighet hos manliga elithockeyspelare." Thesis, Uppsala universitet, Åsenlöf: Fysioterapi, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-402352.
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Bakgrund: Sportfysioterapeuter hjälper atleter att förbättra sport-specifika förmågor. Inom ishockey är slagskottet den skotteknik som producerar den snabbaste puckhastigheten. Handgreppsstyrka har visat sig vara viktig för en hockeyspelares sport-specifika förmågor och klubbrörelser. Skridskohastighet är en viktig variabel sett till hockeyspelares övergripande prestationsnivå. Syfte: Att undersöka den genomsnittliga maximala skotthastigheten, den genomsnittliga maximala handgreppsstyrkan och den genomsnittliga maximala skridskohastigheten hos en grupp manliga svenska elithockeyspelare och undersöka sambandet mellan den maximala skotthastigheten och den maximala handgreppsstyrkan samt skridskohastigheten. Metod: Ett lag på tjugotre manliga elithockeyspelare tillfrågades varav tjugo deltog i studien. Endast utespelare tillfrågades. Tvärsnittstudie med kvantitativ ansats bestående av enstaka mätningar på en grupp. Skotthastighet, handgreppsstyrka och skridskohastighet mättes en gång per testperson vid tre separata tillfällen. Resultat: Sjutton hockeyspelare slutförde studien. Den genomsnittliga maximala skotthastigheten var 128,167 km/h. Den genomsnittliga maximala handgreppsstyrkan var 60,2 kg. Den genomsnittliga skridskohastigheten var 1,405s mätt på en sträcka av 15 meter. Sambandet mellan skotthastighet och handgreppsstyrka var svagt negativt och ej statistiskt signifikant (r=-0,042; p=0,876). Sambandet mellan skotthastighet och skridskohastighet var svagt negativt och ej statistiskt signifikant (r=-0177; p=0,508). Konklusion: De genomsnittliga maximala värdena på skotthastighet, handgreppsstyrka och skridskohastighet är jämförbara med andra studiers värden. Sambandet mellan skotthastighet och handgreppstyrka samt skridskohastighet var svagt vilket pekar på att dessa faktorer inte är en indikator på skotthastigheten vid ett slagskott. Fler studier behövs för att stödja studiens resultat.Background: Sportsfysiotherapists help athletes improve their sport-specific abilities. In ice-hockey, the slap shot is the shot-technique that produces the greatest puck velocity. Hand grip strength have shown to be important to hockey players sport-specific abilities and stick movements. Skating speed is an important variable for the hockey players overall performance. Aim: To investigate the mean hand grip strength, skating speed and shooting speed on a group swedish male elite ice-hockey players and investigate the correlation between these factors. Methods: A team of twentythree male elite hockey players were asked to participate in the study. Twenty players participated. A cross-sectional study with a quantitative approach consisting of single measures on one group. Puck velocity, handgrip strength and skating speed were measured one time per player on three separate sessions. Results: Seventeen hockey players completed the studie. The mean puck velocity was 128,167 km/h. The mean hand grip strength were 60,2 kg. The mean shooting speed were 1,405s measured on a distance of 15 meters. The correlation between puck velocity and hand grip strength were not statistically significant weak negative (r=-0,042; p=0,876). The correlation between mean puck velocity and shooting speed were not statistically significant weak negative(r=-0,177; p=0,508). Conclusion: The mean maximal values of puck velocity, hand grip strength and shooting speed are comparable with similar values from other studies. The correlation between puck velocity and hand grip strength and shooting speed were weak which indicate that these factors do not affect the puck velocity from a slap shot. Further studies are needed to strengthen this study's result.
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Miščenko, Nikolaj. "Nacionalinės futbolo akademijos U-13 metų jaunųjų futbolininkų skirtingų programų poveikis greitumui lavinti." Master's thesis, Lithuanian Academic Libraries Network (LABT), 2014. http://vddb.library.lt/obj/LT-eLABa-0001:E.02~2014~D_20140618_112309-96900.
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Tyrimo objektas: Nacionalinės futbolo akademijos U-13 metų jaunųjų futbolininkų skirtingų programų poveikis greitumui lavinti.
Aktualumas: Šių dienų sporte dideli sportiniai rezultatai yra pasiekiami gana jauname amžiuje, todėl treneriai priversti gerinti atranką, ieškoti gabių vaikų judamąja veiklai. Vienas iš svarbiausių uždavinių yra moksliškai ištirti ir pagrįsti jaunųjų sportininkų rengimo priemonių ir metodų panaudojimo efektyvumą, pritaikyti juos praktinėje veikloje. Didelių sportinių rezultatų galima pasiekti ne tik kryptingai vykdant atranką, ugdant fizines ypatybes bei mokant technikos veiksmų atlikimo, bet ir žinant kiekvieno iš šių sportininkų rengimo komponentų svarbą ir priklausomybę vieno nuo kito įvairiais jaunojo sportininko rengimo laikotarpiais (Skurvydas, 1998; Girdauskas, 2000).
Darbo tikslas: Atskleisti Nacionalinės Futbolo Akademijos U-13 futbolininkų sportinio rengimo programų ypatumus bei parengtumo dinamiką.
Uždaviniai:
1. Nustatyti prieš sportinio rengimo programą Nacionalinės Futbolo Akademijos U-13 futbolininkų greitumo, bei šuolių aukštį be rankų mosto ir mojant rankomis rezultatus.
2. Nustatyti Nacionalinės Futbolo Akademijos didžiausią poveikį turėjusios programos U-13 futbolininkų greitumo, bei šuolių be rankų mosto ir mojant rankomis rezultatų dinamikai.
3. Palyginti ir įvertinti gautus tyrimo rezultatus su kitų šalių analogiškais tyrimo rezultatais.
Tyrimo metodai:
• Literatūros šaltinių analizė.
• Pedagoginis eksperimentas.
• Testavimas... [toliau žr. visą tekstą]The object of research: National football academy of U-13 years young players nominal effect of different programs to quickness development. Relevance: Nowadays remarkable results in sports are achieved at a very early age that is why coaches require higher qualifications for new and talented children to take part in motive activities. One of the most important tasks is to explore and justify efficiency of means and methods used in training junior sportsmen and to apply these methods in practice. Impressive results can be achieved not only through thorough selection of sportsmen, not only by developing physical qualities, or by teaching technique of good performance but also by knowing the importance of training components in each sportsman and correlation between these components in different training periods (Skurvydas, 1998; Girdauskas, 2000). The aim of research: Uncover the National Football Academy U-13 soccer sports training program characteristics and dynamics of fitness. Tasks: 1. To estimate effect before sports training program to the National Football Academy U-13 soccer speed, static jump and jump with arm motion results. 2. To estimate which of sports training program had greatest impact to the National Football Academy U-13 soccer players to their speed, static jump and jump with arm motion results. 3. To compare and evaluate these results with those of other countries with equivalent research. Methods of analysis: 1. Analysis of literary sources. 2... [to full text]
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Kavanaugh, Ashley Anne. "Acute Effects of Whole-Body Vibration on 30 Meter Fly Sprint Performance in NCAA Division I Sprinters and Jumpers." Digital Commons @ East Tennessee State University, 2010. https://dc.etsu.edu/etd/1735.
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The purpose of this study was to identify a potentiation effect on 30 meter (m) fly sprint performance in collegiate sprinters and jumpers (M=21, W=5) following an acute bout of whole-body vibration. The WBV protocol consisted of one 30 second bout at 50 Hz, ~3 mm amplitude, and 60 seconds rest before a 30m fly sprint. Sprint times were measured using timing gates, and characteristics of strength and power were measured using a force plate. Analysis included measures of jump height, peak power, peak force, and rate of force development. Each subject participated in 3 separate trials using randomized treatment sessions over 3 months of preparation training. The control condition consisted of no vibration and WBV treatment 1 and 2 incorporated vibration. Statistics comparing the average sprint times showed no treatment effects. The results of this study indicate that WBV at 50 Hz and ~3 mm amplitude has no effect on sprint times.
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Zimkevičius, Audrius. "Įvairaus amžiaus šuolininkų su kartimi fizinio parengtumo analizė." Bachelor's thesis, Lithuanian Academic Libraries Network (LABT), 2013. http://vddb.laba.lt/obj/LT-eLABa-0001:E.02~2013~D_20130910_154939-40481.
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Tyrimo tikslas – išsiaiskinti Kauno miesto 9-11 ir 12-15 metų bei Lietuvos suaugusių šuolininkų su kartimi fizinį parengtumą, ir palyginti jį su literatūroje rekomenduojamais normatyvais.
Uždaviniai: 1. Nustatyti ir palyginti Kauno miesto 9-11 ir 12 -15 metų šuolininkų su kartimi fizinį parengtumą. 2. Nustatyti ir palyginti Lietuvos suaugusių šuolininkų su kartimi fizinį parengtumą. 3. Nustatyti ir palyginti Lietuvos suaugusių šuolininkų su kartimi testų koreliaciją su varžybiniu rezultatu. 4. Nustatyti ir palyginti Lietuvos suaugusių šuolininkų su kartimi metinio krūvio apimtis.
Hipotezė – Lietuvos suaugusių ir Kauno miesto 9-11 metų ir 12-15 metų šuolininkų su kartimi fizinis parengtumas yra prastesnis, nei nurodyta normatyvuose.
Rezultatai: matome, kad bėgdami 20 m įsibėgėjus ir 30 m bėgime iš aukšto starto 9-11 metų, 12-15 metų šuolininkų bėgimo vidurkiai buvo prastesni nei nurodyta normatyvuose. Abolachovo šuolio testo abiejų šuolininkų grupių rezultatai taip pat yra ženkliai blogesni už normatyvą. Taip pat kojų kelimo prie skersinio kybant ant jo ir prisitraukimų vidurkiai abėjų šuolininkų grupių yra prastesni nei nurodyta normatyvuose. Suaugusių šuolininkų grupėje beveik visų atliktų testų rezultatai buvo prastesni, tik 30 m iš aukšto starto bėgimo vidurkis buvo praktiškai toks pat, kaip ir nurodyta normatyvuose. Taip pat svorio stūmime nuo krūtinės suaugusių šuolininkų su kartimi vidurkis buvo ne daug mažesnis už normatyvą.
Išvados: 1.Kauno 9-11 ir 12-15 m šuolininkų... [toliau žr. visą tekstą]The aim – to find out in Kaunas city 9 – 11 and 12 – 15 years of age boys and Lithuanians adult pole jumpers physical training, and compare it with the literature recommended values. Goals: 1. Identify and compare the city of Kaunas 9 – 11 and 12 – 15 year old pole jumpers physical training. 2. To review and compare the Lithuanian adult jumpers with pole physical training. 3. Identify and compare the Lithuanian adult jumpers with the pole test correlation with the contest results. 4. Identify and compare the Lithuanian adult jumpers with the pole annual charge volume. Hypothesis – Lithuanian adults and Kaunas city 9 – 11 and 12 – 15 year olds pole jumpers physical training is less that the requirement. Results: We can see that running 20 m at cruising speed and 30 m from a standing start 9 -11 and 12 – 15 year olds running averages were lower that the requirement. Abolachovo jump test results between the two groups of children are also significantly lower that the requirement. Also lifting the leg bar by the hover over him and chins averages of both groups of children are lower that the requirement. In adult group, almost all of the tests results were worse, except 30 m from the start of high average was virtually the same as specified in the standards. Also, the weight pushing against the chest adult jumpers with the pole average was a little less that the requirement. Conclusions: 1. Kaunas city 9 – 11 and 12 – 15 jumpers with the pole physical training in almost all of... [to full text]
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Saunders, Nathan David. "High Speed Friction Stir Spot Welding on DP 980 Steel:Joint Properties and Tool Wear." BYU ScholarsArchive, 2012. https://scholarsarchive.byu.edu/etd/3003.
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With the desire to improve passenger safety and fuel efficiency, Ultra High Strength Steels (UHSS) have been developed for use in the automotive industry. UHSS are high strength steels with high ductility and strength. DP 980 is one of these UHSS being applied in automobile manufacturing. DP 980 is difficult to join with Resistance Spot Welding (RSW) because of the high carbon content and alloying in this material. The weld becomes brittle when it solidifies during the welding process. With the desire and motivation of widely using UHSS, new welding processes are needed to be developed in order to effectively join DP 980. Friction Stir Spot Welding (FSSW) is a developing welding process aimed to replace RSW in the automotive industry because of its ability to join materials at a lower temperature. Currently the welding loads of the tools are higher than 2000 pounds, ranging from 3,000 to 5,000 pounds, which exceeds the limit of the welding robots in the automotive factories. It is proposed that the welding loads can be reduced by increasing the spindle speed of the FSSW tool. Other focuses in the research include increasing the life of the tool and developing acceptable welding parameters for High Speed FSSW. The experimental work done for this thesis provided support that weld strength can be obtained at levels above the acceptable standard for DP 980 material (greater than 2400 pound lap shear fracture load for 1.2 mm material) while keeping the vertical load on the welding machine spindle below 2000 lbs.
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Maynard, Robert. "The effects of limb speed and limb preference on selected isokinetic strength and power measures during internal and external rotation of the shoulder." Thesis, Virginia Tech, 1990. http://hdl.handle.net/10919/42059.
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Forty-five males volunteered to serve as subjects to investigate the effects of limb velocity and limb preference on peak torque/body weight (PTBW), torque acceleration energy (TAE), average power (AVP), and endurance ratio (ER) at isokinetic speeds of 60 and 300 degrees/second during internal and external rotation of the shoulder. Standard Cybex warm-up and test protocol were used for both test conditions. Test/retest reliability estimates ranges from r=.60- .70. Repeated Measures ANOVA revealed significant limb speed and limb preference effects on PTBW, TAE, and AVP in both exercise speed or limb preference. The data illustrate a need for an internal/external shoulder rotation normative profile specific to limb speed and limb preference.Master of Science
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Harrison, Alex. "The Bobsled Push Start: Influence on Race Outcome and Push Athlete Talent Identification and Monitoring." Digital Commons @ East Tennessee State University, 2017. https://dc.etsu.edu/etd/3313.
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Bobsled is an Olympic sport that has progressed from rudimentary in the 1800’s to highly technological replete with biomechanical analyses and investment in engineering from the world’s top engineers. Little to no investigation has been carried out on all the tracks and the interrelationship between various measures of starts and sled-travel down-track. Further, little quality research has been produced in the athletic characteristics required for high-level competition in bobsled.
The present manuscript investigates the reliability of, and interrelationship between, start time, start velocity, split times, and finish times in World Cup 2- and 4-man bobsled competition. A strong relationship between the three variables is found, but further research is needed to elucidate the actual effects of the push start on the sled’s travel down-track because of several confounding variables.
The present manuscript also investigates the tests commonly performed by the USA Bobsled and Skeleton federation as a means of talent identification and athlete monitoring. Strength and power tests may have more validity for discriminating between higher-level push athletes, so long as a sufficient threshold of running speed is present. Speed tests only discriminate well between lower level push athletes. Recommendations are made for modifying the current testing battery in such a way as to better identify talent and better monitor traveling athletes and informing coaching decisions about athlete preparedness for fast bobsled push starts.
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Kemper, Courtney Paige. "Association Among Physical Activity, Protein, Intake and Clinical Indicators of Sarcopenia." Miami University / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=miami1605816952601922.
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Borges, Juliano Henrique 1989. "Efeitos de sete semanas de treinamento com pliometria ou sprint resistido na aceleração e sprints repetidos no final do período competitivo em jovens atletas de futebol." [s.n.], 2014. http://repositorio.unicamp.br/jspui/handle/REPOSIP/275055.
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Orientador: João Paulo BorinDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Educação Física
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Resumo: A ciência do esporte tem investido em estudos com atletas de futebol com o intuito de desenvolver alternativas para melhorar a aceleração no período competitivo. Foi demonstrado que ao final de um período competitivo atletas de futebol têm uma queda de até 4,3 % da aceleração. Especificamente o sprint, pode ser determinante para o futebol, e manter alta intensidade durante sequências de sprint é de suma importância. Portanto, produzir sprints subsequentes é um componente físico definido como capacidade de sprints repetidos (CSR). Alguns estudos têm mostrado altas correlações da aceleração com a CSR. Consequentemente, melhorar a aceleração pode ser uma estratégia para melhorar a CSR. Nenhum estudo comparou programas de treinamento com o método de pliometria e sprint resistido, com o intuito de melhorar a aceleração e a CSR durante a temporada. Objetivos: Comparar os efeitos de programas de treinamento com pliometria (GTP) e sprint resistido (GSR) na aceleração e na CSR em jovens atletas de futebol. Materiais e Métodos: Participaram do estudo 20 atletas adolescentes (16,6 ± 0,6 anos), que realizaram 12 sessões de GTP (n = 11) ou GSR (n = 9) por 7 semanas. O GTP consistiu de quatro exercícios (salto bilateral sobre barreiras, salto de força reativa sobre caixas, salto unilateral sobre barreiras e salto em profundidade sobre barreiras) progredindo de 2 a 7 séries de 10 repetições com recuperação de 120 s entre as séries. O GSR consistiu de quatro exercícios de sprints nas distâncias de 0-5; 0-10; 0-20 e 0-30 m, com progressão de 2 a 7 séries, cargas entre 10 a 13% da massa corporal, com tração por meio de um trenó e com recuperação entre 45 a 120 s. Os atletas foram avaliados antes e depois do período de treinamento, nos quais realizaram testes de sprints na distância de 0-30 m (0-5; 5-30 e 0-30 m) e o teste de Repeated-Sprint Ability (RSA) (melhor tempo [RSAMáx] e média dos tempos [RSAMed]). Utilizou-se a análise de modelo misto para medidas repetidas (interação grupo x tempo) com nível de significância de ??0,05. Também foi realizada análise qualitativa utilizando a magnitude do efeito de tratamento (effect size) e a precisão de estimativa da magnitude do efeito de grupo e tempo (intervalo de confiança do effect size). Resultados: O GSR induziu melhoras no tempo de sprint para 0-5 (-0,9 ± 8,2 % [d = 0,19] vs. 3,9 ± 11,0 % [d = -0,63]); 5-30 (-1,1 ± 1,7 % [d = 0,30] vs. -0,1 ± 3,3 % [d = 0,14]) e 0-30 m (-1,1 ± 2,8 % [d = 0,37] vs. 0,7 ± 3,5 % [-0,17]); RSAMáx (-1,2 ± 2,6 % [d = 0,73] vs. 0,8 ± 3,3 % [d = -0,21]) e RSAMed (-1,6 ± 2,3 % [d = 0,95] vs. -0,5 ± 2,2 % [d = 0,16] comparando com GTP. Conclusões: O GSR foi mais eficiente que o GTP em melhorar a aceleração e a CSR ao final da temporada, visto que é um período que atletas são suscetíveis a declínio dessas capacidades físicas
Abstract: The sports science has invested in studies with soccer players in order to develop alternatives to improve the acceleration in the season. It has been demonstrated that in the end of the season soccer players have a drop of up to 4.3% from acceleration. Specifically the sprint, can be decisive for this sport, and maintain high intensity during sprint sequences has a paramount importance. Therefore, reproduce a high power output in subsequent sprints is defined repeated sprint ability (RSA). Some studies have shown high correlation of acceleration with RSA. Accordingly, improve acceleration may be a strategy to improve RSA. To date, no study has shown programs and compared methods as plyometrics and resisted sprint training, in order to improve the acceleration and RSA in season. Objectives: To compare the effects of plyometrics (GPT) and resisted sprint (GRS) training programs on acceleration and RSA in young soccer players. Materials and Methods: The study included 20 adolescent athletes (16.6 ± 0.6 years) who performed 12 sessions of GPT (n = 11) or GRS (n = 9) for 7 weeks. The GPT consisted of four exercises (bilateral hurdle jump, drop jump; unilateral hurdle jump; depth jump over hurdle) progressing from 2-7 sets of 10 reps interspersed with 120 s. The GRS consisted of four sprints exercises at distances of 0-5, 0-10, 0-20 and 0-30 m, progressing from 2-7 sets, loads between 10-13 % of the body mass, with resistance by a sled interspersed with 45 to 120 s. The athletes were evaluated before and after the training period, in which performed tests of sprints at distance of 0-30 m (0-5, 5-30 and 0-30 m) and RSA test (best time [RSAbest] and mean time [RSAmean]). It was used the mixed model for repeated measures (group x time interaction) with significance level of ? ? 0.05. It was also performed the qualitative analysis using the magnitude of treatment effect (effect size) and precision of the estimate of the magnitude of the effect (effect size confidence intervals). Results: GRS induced greater improvements in sprint time of 0-5 (-0.9 ± 8.2 % [d = 0.19] vs. 3.9 ± 11.0 % [d = -0.63]); 5-30 (-1.1 ± 1.7 % [d = 0.30] vs. -0.1 ± 3.3 % [d = 0.14]) and 0-30 m (-1.1 ± 2.8 % [d = 0.37] vs. 0.7 ± 3.5 % [-0.17]); RSAbest (-1.2 ± 2.6 % [d = 0.73] vs. 0.8 ± 3.3 % [d = -0.21]) and RSAmean (-1.6 ± 2.3 % [d = 0.95] vs. -0.5 ± 2.2 % [d = 0.16] compared with GPT. Conclusions: GRS was more effective than GPT to improve acceleration and RSA in the end of the season, whereas is a period that players are more susceptible to drop these abilities
Mestrado
Biodinamica do Movimento e Esporte
Mestre em Educação Física
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Simpson, Nathaniel Denis John. "An analysis of tensile strength, fracture initiation and propagation in anisotropic rock (gas shale) using Brazilian tests equipped with high speed video and acoustic emission." Thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for petroleumsteknologi og anvendt geofysikk, 2013. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-24284.
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This study attempts to further our knowledge of fracture behaviour by establishing an experimental system that links tensile strength, fracture initiation and propagation of an anisotropic rock (Mancos Shale) using an integrated Brazilian Test Setup equipped with Acoustic Emission and High Speed Video. The unique experimental conguration was applied to an anisotropic gas shale (Mancos Shale) in addition to other petroleum related reservoir rocks (such as sandstone and chalk). The variation in tensile strength, fracture initiation location, propagation time and the failure pattern are examined as a function between the layer plane and the loading direction. A time shift was shown to exist between the time at ultimate tensile stress and the time at fracture initiation. This phenomenon has been dubbed the Naet Shift.
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Cormack, Stuart J., and n/a. "The changes in strength, power and associated functional physiological measures in elite women soccer players during a 12 month preparation for a major event." University of Canberra. Health and Biomedical Science, 2003. http://erl.canberra.edu.au./public/adt-AUC20050411.134745.
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The assessment of strength and power and the relationship of these measures to
functional variables such as speed and vertical jump ability are understood poorly.
This is particularly the case when dealing with a long-term preparation for a major
event in a sport such as women's soccer.
The results of this research suggest that a number of isoinertial speed strength
measures may be sensitive to aspects of a training program and therefore be useful
tools for determining the level of development of various underlying neuromuscular
capacities.
Further results provide a question mark about the role of maximum strength in the
development of high velocity functional movements, as increases in maximum
strength did not correlate to changes in measures of functional performance.
An important finding from this research is the potential role of specific isoinertial
speed strength parameters in the detection of neuromuscular fatigue. Time course
analysis of the results in this study suggests that the use of these measures to detect
fatigue warrants further investigation.
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Mladen, Mikić. "Хронични и акутни ефекти изоинерцијалног тренинга на доминантне моторичке способности кошаркаша јуниорског узраста." Phd thesis, Univerzitet u Novom Sadu, Fakultet sporta i fizičkog vaspitanja u Novom Sadu, 2018. https://www.cris.uns.ac.rs/record.jsf?recordId=107372&source=NDLTD&language=en.
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Циљ истраживања је да се утврде ефекти 8 недеља изоинерцијалног тренинга на доминантне моторичке способности кошаркаша. Испитаници, 36 кошаркаша јуниорског узраста (17.58±0.50 година) су подељени у 3 групе: прву експерименталну (ЕСС; n=12) која је вежбала тренинге снаге на изоинерцијалном тренажеру, другу експерименталну (CON; n=12) која је вежбала традиционални изодинамички тренинг снаге са слободним теговима, и контролну групу (KON; n=12) која није вежбала тренинге снаге. Током есперименталног програма ЕСС и CON групе су имале укупно по 12 тренинга снаге са истоветним бројем серија и понављања. На крају четврте недеље код обе експерименталне групе спроведен је тест постактивацијске потенцијације (ПАП) како би се утврдили акутни ефекти различитих метода тренинга у 4 временске тачке: 2, 4, 8 и 15 минута након вежби са оптерећењем. Резултати су показали да постоји статистички значајна разлика као последица примене различитих метода тренинга снаге у трајању од 8 недеља при чему је изоинерцијални тренинг довео до значајно бољих резултата у варијаблама скокова SJ, CMJ, VJ и у скоку са леве ноге CMJLN, затим у тесту спринта 5 m и тестовима агилности Т тест и 505 са окретом око десне ноге. Нису утврђене статистички значајне разлике у тестовима изометријске снаге, скока са десне ноге CMJDN, трчања 20 m и тесту агилности 505 са окретом око леве ноге. У тесту ПАП ефеката није било статистички значајне разлике у резултатима као последице различитих метода вежбања. При томе, СОN група је имала значајно побољшање у тесту скока VJ док је код ЕСС групе значајан ефекат у варијаблама скока VJ и Т тест агилности. Није било значајних ефеката ПАП у тестовима трчања 5 и 20 метара. Добијени резултати указују да изоинерцијални тренинг у трајању од 8 недеља доводи до бољих резултата у развоју експлозивне снаге, брзине и агилности младих кошаркаша у поређењу са традиционалним изодинамичким тренингом, али не и у ПАП ефектима. У складу с тим, тренери и кондициони тренери би требали да у раду са младим спортистима користе и ову методу тренинга снаге.Cilj istraživanja je da se utvrde efekti 8 nedelja izoinercijalnog treninga na dominantne motoričke sposobnosti košarkaša. Ispitanici, 36 košarkaša juniorskog uzrasta (17.58±0.50 godina) su podeljeni u 3 grupe: prvu eksperimentalnu (ESS; n=12) koja je vežbala treninge snage na izoinercijalnom trenažeru, drugu eksperimentalnu (CON; n=12) koja je vežbala tradicionalni izodinamički trening snage sa slobodnim tegovima, i kontrolnu grupu (KON; n=12) koja nije vežbala treninge snage. Tokom esperimentalnog programa ESS i CON grupe su imale ukupno po 12 treninga snage sa istovetnim brojem serija i ponavljanja. Na kraju četvrte nedelje kod obe eksperimentalne grupe sproveden je test postaktivacijske potencijacije (PAP) kako bi se utvrdili akutni efekti različitih metoda treninga u 4 vremenske tačke: 2, 4, 8 i 15 minuta nakon vežbi sa opterećenjem. Rezultati su pokazali da postoji statistički značajna razlika kao posledica primene različitih metoda treninga snage u trajanju od 8 nedelja pri čemu je izoinercijalni trening doveo do značajno boljih rezultata u varijablama skokova SJ, CMJ, VJ i u skoku sa leve noge CMJLN, zatim u testu sprinta 5 m i testovima agilnosti T test i 505 sa okretom oko desne noge. Nisu utvrđene statistički značajne razlike u testovima izometrijske snage, skoka sa desne noge CMJDN, trčanja 20 m i testu agilnosti 505 sa okretom oko leve noge. U testu PAP efekata nije bilo statistički značajne razlike u rezultatima kao posledice različitih metoda vežbanja. Pri tome, SON grupa je imala značajno poboljšanje u testu skoka VJ dok je kod ESS grupe značajan efekat u varijablama skoka VJ i T test agilnosti. Nije bilo značajnih efekata PAP u testovima trčanja 5 i 20 metara. Dobijeni rezultati ukazuju da izoinercijalni trening u trajanju od 8 nedelja dovodi do boljih rezultata u razvoju eksplozivne snage, brzine i agilnosti mladih košarkaša u poređenju sa tradicionalnim izodinamičkim treningom, ali ne i u PAP efektima. U skladu s tim, treneri i kondicioni treneri bi trebali da u radu sa mladim sportistima koriste i ovu metodu treninga snage.
The aim of this research is to determine the effects of an 8-week isoinertial training on dominant motor abilities of basketball players. Examinees, i.e. 36 junior basketball players, (17.58±0.50 years) are divided into 3 groups: the first experimental group (ECC; n=12) which took strength training exercises on isoinertial training device, the second experimental (CON; n=12) which took traditional isodynamic strength training with free weights, and a control group (CON; n=12) which did not take any strength training exercises. During the experimental program, the ECC and CON groups had 12 strength training sessions in total including the same number of series and repetitions. At the end of the fourth week, both experimental groups were tested for post-activational potentiation (PAP) in order to determine acute effects of different training methods in 4 time points: 2, 4, 8 and 15 minutes after loading exercises. The findings indicate that there is a statistically significant difference as a result of the application of different strength training methods lasting for 8 weeks, since the isoinertial training brought about significantly better results in the variables of jumps SJ, CMJ, VJ and jump off the left foot CMJLN, as well as in the 5m sprint test and agility tests (T-test and 505 test with turn on the right leg). No statistically significat differences were found in tests of: isometric strength, jump off the right foot CMJDN, 20m run and 505 agility test with the turn on the left leg. Also, there were no statistically significant differences as a result of different exercise methods in the PAP test. In that process, CON group had significant improvement in VJ jump test, whereas in ECC group a significant effect was found in the variables of VJ and agility T-test. The 5m and 20m run tests showed no significant PAP effects either. In comparison with the traditional isodynamic training, the findings indicate that isoinertial training lasting for 8 weeks gives rise to better results in the development of explosive strength, speed and agility of young basketball players. Accordingly, coaches and trainers should use this method of strength training in work with young athletes.
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Israetel, Michael Alexandrovich. "The Interrelationships of Fitness Characteristics in Division 1 Athletes." Digital Commons @ East Tennessee State University, 2013. https://dc.etsu.edu/etd/1194.
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The purpose of this dissertation was to explore the interrelationships of several important fitness characteristics in Division 1 athletes. Sport performance magnitude is the summation of an individual athlete’s technical, psychological, and fitness characteristics. Athletes who excel in any or all characteristics perform better in their chosen sports. General fitness characteristics that are important to almost all sports include strength, power, vertical jump height, shortdistance sprinting ability, muscularity, and body fat percentage. These variables have been shown in previous research to independently affect athletic performance outcomes, but their relationships to one another are less clear. Eighty Division I athletes from 4 sports were examined in a variety of fitness characteristics as part of a continuous athlete monitoring program. Data on strength, power, vertical jump height, short-distance sprinting speed, muscularity, and body fat percentage were collected and analyzed. Analysis revealed several important relationships. Firstly, strength is highly related to muscularity, with lean body mass as one of the most important determinants of strength. Secondly, athletes who can produce high relative (scaled per body mass) forces and powers tend to be considerably higher jumpers and much faster sprinters. Lastly, leaner athletes out-perform less lean athletes in almost every metric, especially relative strength and power, vertical jumping ability, and sprinting ability.
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Lukic, Bratislav. "Mise au point d'une technique de mesure de champs pour la caractérisation du comportement dynamique du béton en traction." Thesis, Université Grenoble Alpes (ComUE), 2018. http://www.theses.fr/2018GREAI028/document.
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Ce travail thèse a pour objet une méthode expérimentale combinant un essai de traction indirect par écaillage et une mesure de champs à partir d’images obtenues par caméra ultra rapide, ceci à des fins d’identification des propriétés de rupture du béton sous chargement de traction dynamique. Cette méthode, proposée dans la littérature peu de temps avant le démarrage de ces travaux, fait ici l’objet d’une étude approfondi ainsi que d’une série de développements et d’amélioration. Les images obtenues sont traités par une technique de grille et la méthode des champs virtuels est appliquée pour identifier le comportement local des matériaux quasi-fragiles soumis à de hautes vitesses de déformation (plusieurs 100 1/s}). Dans un premier temps, afin de valider la technique de traitement maus aussi d’étudier l’incertitude de mesure associée, un simulateur de la chaîne de mesure complète a été mis au point. Il a été ainsi possible d’étudier l’influence de différentes sources potentielles d’erreurs qui peuvent être rencontrées dans le protocole expérimental. Cette étude a permis de retenir des recommandations sur les conditions de réalisations réelles de l’essai afin d’améliorer la fiabilité des mesures obtenues. D’un point de vue expérimental, différents capteurs ultra haute vitesse ont été utilisés afin d’étudier leur performances vis-à-vis des mesures réalisées. Ainsi, les campagnes d’essais ont été réalisées sur un matériau aux caractéristiques bien identifiées permettant l’étude des performances métrologiques de toute la chaine d’identification, pour chaque modèle de capteur. Enfin, le protocole expérimentale a été mis en place pour étudier le comportement de plusieurs types de béton soumis en traction dynamique. L’objectif, ici, est d’identifier leur comportements mécaniques ainsi que leur caractéristiques de rupture et fragmentation sous traction dynamique. En ce qui concerne la résistance à la traction, les valeurs identifiées dans cette étude sont inférieures, pour chaque cas, à celles rapportées dans la littérature et obtenues, pour la plupart, à partir du traitement de la vitesse matérielle mesurée en face arrière de l’échantillon. Pour ce qui est de l’énergie spécifique de rupture, les valeurs obtenues dans ces travaux sont égalements inférieures à celles publiées dans les revues scientifiquesIn this thesis a recently proposed photomechanical spalling experiment has been used in light of identifying concrete failure properties under dynamic tension.The experimental technique uses ultra-high speed imaging, the grid method and the virtual fields method.First, in order to investigate the accuracy and validate the processing technique, a methodology of using simulated experiments has been developed by numerically simulating the entire identification process.In this way, several potential sources of errors have been investigated allowing to place guidelines on how to perform the experiment in a more reliable manner.Second, several latest ultra-high speed acquisition systems have been used in order to investigate their contribution to a possible measurement refinement.In this case, the trial experiments have been conducted on a material of known characteristics which allowed investigating the metrological performance of the acquisition system on the entire identification chain.Finally, the experimental methodology has been applied to testing several grades of concrete in light of identifying the material constitutive response as well as their fracturing characteristics under dynamic tension.The identified tensile strengths in this work were found to be consistently lower than those obtained from the standard processing of the rear-face velocity profile.Moreover, the values of the identified specific fracture energy were also found to be markedly lower than the ones often reported in the literature
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Parker, James. "A multi-disciplinary approach to studying performance among high-level golfers : physiological and biomechanical aspects." Licentiate thesis, Högskolan i Halmstad, Rydberglaboratoriet för tillämpad naturvetenskap (RLAS), 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:hh:diva-37792.
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In competitive golf, the player’s ability to hit the ball a long distance affects the score in a positive way. Swing kinematics is considered an important factor in driver performance; one way of improving swing kinematics is through strength and power training. Subsequently, high-level golfers and their coaches often explore novel ways of increasing the distance of a shot, in particular driver carry distance (CD). This licentiate thesis presents two studies with the overall aim of studying how swing kinematic and physical characteristics are associated with driver performance among intercollegiate golf players. The studies report swing kinematics associated with driver performance (study 1) and the impact of isokinetic rotational training on driver performance and swing kinematic variables (study 2). The methods used were (1) a cross-sectional correlation study (n=15) and (2) an open trial intervention study (n=20). The studies investigated (1) the relationship between golf swing kinematics and driver performance, and (2) the impact of strength training on swing kinematics and driver performance variable. The results show variables that were distinctive for the club head speed (CHS) were mainly during the downswing: greater X-factor stretch; and higher pelvis peak speed. Whilst, factors distinctive to the regression model for CD were mainly at impact: reduced thorax rotation; and greater thorax lateral bend. Nine weeks of isokinetic training increased seated rotational force and power, peak arm speed and arm acceleration, ball speed, and CD more compared to isotonic training. Even though isokinetic training did not increase CHS, it did result in greater CD. This licentiate thesis contributes to the understanding of which variables influence driver performance, in particular CD, among high-level golfers. Segmental interactions (pelvis-thorax), lead arm speed and acceleration, isokinetic and isotonic training. These results may guide training interventions aiming to improve driver and golf performance among high-level golfers, particularly those with a background of strength training. Future studies could investigate how the interaction between swing kinematics, clubhead trajectory, and driver performance variables differ between male and female golfers.
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Hallgren, Adam. "Det avlastande bärsystemets påverkan på att bära en sjukbår : en studie baserad på prov och försök." Thesis, Försvarshögskolan, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:fhs:diva-9881.
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For a wounded soldier to have as good a chance of survival as possible, an important variable during care is the time it takes for the wounded to get to a high-quality medical facility where there is expertise in surgery. If the injured person is to be transported with a stretcher carried by other soldiers, the speed for which this can be done is limited by the strength of the bearer in the hands and forearms.This study aims to explore how the speed and perceived ergonomics of those who carry a stretcher can change for a group if it is issued a relieving carrying system that redistributes the load of the stretcher to the hips, back and legs. The study is largely based on a study by Knapik et al (2000) where similar tests were done in a controlled indoor environment but where this study was done in a field environment with groups of 2 or 4 people carrying a stretcher.The study is done in the form of tests and experiments with conscripts from Skaraborg Wing, F 7. The conscripts carried a stretcher in a field-like environment where speed, comfort and usability were in focus. The study was also done with a questionnaire belonging to the experiments to value the experience.The study resulted in a relieving carrying system integrated in the Swedish Armed Forces' combat vest 2000 having an increased average speed with the median 30.7% when carrying a stretcher loaded with 100 kg. The analysis shows that it is above all women who benefit greatly from not carrying a stretcher with their hands. Something they are statistically worse at than men. The study also shows that there are tendencies that the comfort is improved for a soldier.För att en sårad soldat ska ha så goda chanser till överlevnad som möjligt är en viktig variabel under omhändertagandet tiden det tar för den sårade att komma till en högkvalitativ sjukvårdsinrättning, där det finns expertis inom kirurgi. Om den skadade ska transporteras med sjukbår som bärs av andra soldater, är hastigheten för vilket detta kan göras begränsad av de bärandes styrka i händer och underarmar.Denna studie syftar till att utforska hur hastigheten samt den upplevda ergonomin för de som bär en sjukbår kan förändras för en grupp om den tillförs ett avlastande bärsystem som omfördelar lasten till höfter, rygg och benen. Studien baseras till stor del på en studie av Knapik med flera (2000) där liknande tester gjordes i en kontrollerad inomhusmiljö, men där denna studie är gjord i en fältmiljö med grupper om 2 eller 4 personer som bär en sjukbår.Studien är gjord i form av prov och försök med värnpliktiga ur Skaraborgs Flygflottilj, F 7, som bär en bår i en fältliknande miljö där hastigheten, komforten och användbarheten stod i fokus. Studien är även gjord med en enkätundersökning tillhörande försöken i syfte att skatta upplevelsen.Studien resulterade i att ett avlastande bärsystem integrerat i Försvarsmaktens stridsväst 2000 medförde en ökad snitthastighet, med medianen 30,7%, vid bärande av en sjukbår 2 lastad med 100 kg. Analysen påvisar att det framför allt är kvinnor som har stor nytta av att inte bära en sjukbår med händerna, något de statistiskt sett är sämre på än män. Studien visar även att det finns tendenser för att komforten förbättras för en soldat men användbarheten är oförändrad.
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Santos, Jonatas Ferreira da Silva. "Efeito agudo da potencialização pós-ativação sobre o desempenho do salto vertical com contramovimento e no frequency speed of kick test em atletas de taekwondo." Universidade de São Paulo, 2014. http://www.teses.usp.br/teses/disponiveis/39/39134/tde-28082014-095208/.
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O objetivo deste estudo foi investigar o efeito dos exercícios meio-agachamento, salto e complexo (agachamento + saltos), seguido por intervalos de 5 min, 10 min ou auto-selecionado sobre o desempenho no salto vertical com contramovimento (CMJ - countermovement jump) e frequency speed of kick test (FSKT). Para isso, 11 atletas de taekwondo, faixas-preta foram submetidos a nove protocolos experimentais e um controle realizados aleatoriamente. Cada sessão experimental foi composta pelo aquecimento, uma atividade condicionante (meio-agachamento: três séries de uma repetição a 95% de 1RM; pliometria: três séries de 10 saltos sobre barreira de 40 cm; ou exercicio complexo: meio-agachamento com três séries de duas repetições a 95% de 1RM seguido por quatro saltos sobre barreira de 40 cm), e um intervalo (5 min, 10 min ou intervalo auto-selecionado) antes da realização do CMJ e FSKT. Houve diferença estatisticamente significativa sobre o número de golpes aplicados (F9,90 = 2,90; P = 0,005, h2 = 0,225 [pequeno]). O exercício complexo com intervalo de 10 min (23 ± 5 repetições) foi superior a condição controle (19 ± 3 repetições), meio-agachamento com intervalo auto-selecionado (18 ± 2 repetições, P = 0,015) e saltos com intervalo de 5 min (18 ± 3 repetições, P < 0,001). Nossos resultados indicam que atletas de taekwondo podem aumentar o número de golpes aplicados em teste específico após a realização do exercício complexo. Outro objetivo deste estudo foi investigar o efeito do volume e intensidade sobre o desempenho no CMJ e FSKT. Para isso, nove atletas de taekwondo, faixaspreta foram submetidos a quatro sessões experimentais e uma sessão controle realizadas aleatoriamente. Cada sessão experimental foi composta pelo aquecimento, uma atividade condicionante no exercício meio-agachamento (sessões experimentais: uma série de três repetições a 50% ou 90% de 1RM ou três séries de três repetições a 50% ou 90% de 1RM), seguido por intervalo de 10 min antes da realização do CMJ e cinco séries do FSKT. O desempenho do FSKT caiu ao longo das séries (F3,21;128,36 = 25,344; P < 0,001, h2 = 0,388 [muito grande]). Não houve efeito do volume e intensidade sobre as variáveis investigadas. Nossos resultados indicam que os atletas de taekwondo não foram afetados pelo uso de diferentes volumes e intensidades em atividade de potência específica e não específica visando a manifestação da potencialização pós-ativaçãoThe purpose of this study was to investigate the effect of half-squat, jump and complex exercise (half-squat + jump), followed by intervals of 5-min, 10-min or selfselected rest interval on performance of countermovement jump (CMJ) and the frequency speed of kick test (FSKT). Eleven black-belt taekwondo athletes were randomly submitted to nine experimental section and one control were randomly. Each experimental section was composed by warm-up, conditioning activity (halfsquat: three sets of one repetition at 95% of 1-RM; plyometric: three sets of 10 jumps above 40-cm barrier; or complex exercise: half-squat with three sets of two repetitions at 95% of 1-RM followed for four jumps above 40-cm barrier), and a rest interval (5-min, 10-min or self-selected rest interval) before performing CMJ and FSKT. There was statistically significant difference regarding the number of kicks applied (F9,90 = 2.90; P = 0.005, h2 = 0.225 [small]). The complex exercise with 10- min of rest interval (23 ± 5 repetitions) was higher that the control (19 ± 3 repetitions), as well as the half-squat with self-selected rest interval (18 ± 2 repetitions, P = 0.015) and the plyometric with 5-min rest interval (18 ± 3 repetitions, P < 0.001). Our results indicate that taekwondo athletes can increase the number of kicks applied in a specific test after perfoming the complex exercise. An other purpose of this study was to investigate the effect of volume and intensity of CMJ and FSKT. Nine blackbelt taekwondo athletes were randomly submitted to four experimental section and one control. Each experimental section was composed by warm-up, one conditioning activity on half-squat exercise (experimental section: one set of three repetitions at 50% or 90% 1-RM or three sets of three repetitions at 50% or 90% of 1-RM), followed by 10-min of interval before performance of CMJ and five sets of FSKT. The FSKT performance declined along of sets (F3,21;128,36 = 25.344; P < 0.001, h2 = 0.388 [very large]). It was not found difference regarding exercise volume and intensity on the investigated variables. Our results indicate that taekwondo athletes were not affected by different volume and intensities of specific and non-specific power activities on post-activation potentiation
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Petrauskas, Marius. "Lietuvos jaunių merginų krepšinio rinktinės žaidėjų fizinio pajėgumo, dėmesio sutelktumo ir reakcijos laiko pokyčiai rungtyniaujant dvi dienas iš eilės." Master's thesis, Lithuanian Academic Libraries Network (LABT), 2011. http://vddb.laba.lt/obj/LT-eLABa-0001:E.02~2011~D_20110628_095949-83447.
Full textAbstract:
Tyrimo aktualumas - yra žinoma, kad sportininkams rungtyniaujant rinktinių čempionatuose ar turnyruose yra gaunamas labai didelis fizinis krūvis. Kartais tenka sužaisti 2-3 rungtynes per dvejas, trejas dienas. Dėl šios priežasties, šiame tyrime bus analizuojamas dviejų dienų varžybinis laikotarpis plačiau ir įvertinama jėgos, greitumo, reakcijos, dėmesio sutelktumo rodiklių kaita. Tai padės geriau įvertinti krepšininkių pasirengimą kelių dienų varžybiniam laikotarpiui. Pasiruošimo krepšinio čempionatams metu, treneriai turės daugiau informacijos kokių fizinių savybių tobulinimui skirti didesnį dėmesį, atsižvelgdami į mūsų tyrimo gautus rezultatus.
Tikslas – nustatyti Lietuvos jaunių merginų krepšinio rinktinės žaidėjų fizinio pajėgumo, dėmesio sutelktumo ir reakcijos laiko pokyčius rungtyniaujant dvi dienas iš eilės.
Uždaviniai:
1. Nustatyti krepšininkių fizinį pajėgumą, dėmesio sutelktumą ir reakcijos laiko pokyčius prieš, per ir po pirmųjų rungtynių.
2. Nustatyti krepšininkių fizinį pajėgumą, dėmesio sutelktumą ir reakcijos laiko pokyčius prieš, per ir po antrųjų rungtynių.
3. Palyginti krepšininkių fizinio pajėgumo, dėmesio sutelktumo ir reakcijos laiko pokyčius tarp pirmųjų ir antrųjų rungtynių.
Išvados: 1. Iškart po pirmosios dienos rungtynių sumažėjo 20 m bėgimo greitis ir maksimalios valingos jėgos momentas.
2. Antrosios rungtynės reikšmingai sumažino tik sudėtingosios reakcijos laiką.
3. Lyginant pirmųjų ir antrųjų rungtynių rezultatus antros dienos rungtynių... [toliau žr. visą tekstą]The purpose of this study – there is known, that there is produced very high physical activity for sportsmen participating in championships or tournaments of squads. At times they have to play 2-3 competitions in two-three days. Because of this reason, there will be more fully analyzed two-days competition period strength, speed, reaction and attention concentration change of rates estimated. This will help to evaluate better the bakstetball players preparation for a few days competition. Our analysis results will give more information for coatches to which physical properties needs to concentrate in period of prepartion for championship of basketball. The aim – determine the changes of physical fitness, concentration of attention and reaction time of Lithuanian junior girls’ basketball squad players, playing two days in a row. Tasks: 1. To determine the changes for basketball players of physical fitness, concentration of attention and reaction time before, at and after the first competition. 2. To determine the changes for basketball players of physical fitness, concentration of attention and reaction time before, at and after the second competition. 3. To compare the changes for basketball players of physical fitness, concentration of attention and reaction time between the first and the second competitions. Conclusions - 1. At once after the firts competition 20 m runing speed and maximum voluntary conraction force moment decreased. 2. The second competition... [to full text]
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Sandlund, Stefan. "Kvinnliga elitinnebandyspelares fysiska profil : En beskrivning av utespelare." Thesis, Umeå universitet, Idrottsmedicin, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-149626.
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Bakgrund: Innebandy är en intensiv sport där snabba upprepade accelerationer och riktningsförändringar är viktiga ingredienser för framgång. Även om både förflyttningssnabbhet och uthållighet är viktiga för prestationen i innebandy, finns inga studier som undersöker hur de relaterar till varandra och andra viktiga fysiska kvaliteter. Syfte: Att beskriva kvinnliga elitinnebandyspelares fysiska egenskaper och undersöka korrelationen mellan snabbhet i förflyttningar, aerob uthållighet, maximal styrka och explosivitet. Metod:19 kvinnliga elitinnebandyspelare i åldern (medel (SD)) 21,8år (±2,15), längd 168,8cm (±5,8) långa och vikt 65,9 kg (±6,3), rekryterades till studien. Ett testbatteri genomfördes över två dagar och bestod av snabbhetstester (Acc10, Acc20m, Pro-agility), explosivstyrketester (SLH, SJ, CMJ, CMJ:A), maximalstyrketest (IPU) och aerob uthållighet (Beeptest). Korrelationen mellan testresultaten analyserades. Resultat: Det fanns starka korrelationer mellan förflyttningssnabbhet och prestationen explosiv styrka, utom mellan vertikalhopp med armsving (CMJ:A) och snabbhet i riktningsförändringar (Pro- agility). Isometrisk styrka (IPU) relaterade endast signifikant till snabbhet i riktningsförändringar (Pro-agility), vilket också aerob uthållighet (Beeptest) gjorde. Slutsats: För kvinnliga elitinnebandyspelare finns ett samband mellan explosiv styrka och snabbhet i alla förflyttningar, medan maximalstyrka endast verkar relatera till snabbhet i riktningsförändringar. Arbetsförmågan i aerob uthållighetsarbeten verkar inte påverka prestationen i snabbhet negativt, utan på den här prestationsnivån kan båda utvecklas till tillräcklig nivå.Background: Floorball is an intense sport where rapid repeated accelerations and changes of direction are important ingredients for success. Although both the locomotion speed and endurance are essential for achievement in floorball, there are no studies examining how they relate to each other and other important physical qualities. Objective: To describe female elite Floorball player's physical properties and examine the correlation between locomotion speed, aerobic endurance, maximum strength and explosiveness. Method: 19 female elite Floorball players age (mean (±SD)) 21, 8 years (±2.15), height 168, 8 cm (±5.8) and weight (65.9 kg±6.3), were recruited to the study. A test battery was conducted over the span of two days and consisted of tests of locomotion speed (Acc10, Acc20, Pro-agility), explosive strength (SLH, SJ, CMJ, CMJ:A), maximum strength (IPU) and aerobic endurance (Beep test). The correlation between the test results were analyzed. Results: There were strong correlations between locomotion speed performance and explosive strength, except between vertical jump with arm swing (CMJ) and speed in changes of direction (the Pro agility). Isometric strength (IPU) significantly related to the speed in changes of direction (the Pro agility), as did aerobic endurance (Beeptest). Conclusion: For female elite Floorball players there seems to be a correlation between explosive strength and quickness in all types of locomotion, while the maximum strength only seems to relate to the speed in changes of directions. Work ability in aerobic endurance tasks does not seem to affect performance in locomotion speed, and at this performance level both can be developed to a sufficient level.
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Vlasenko, Vitalijus. "Pasyvaus šildymo poveikis žmogaus kojų raumenų susitraukimo galingumui minant veloergometrą bei atliekant vertikalius šuolius." Master's thesis, Lithuanian Academic Libraries Network (LABT), 2005. http://vddb.library.lt/obj/LT-eLABa-0001:E.02~2005~D_20050519_083034-92864.
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The aim of the study is to determine effects of passive warming up on muscle contraction force while performing maximum intensity short veloergometric test and vertical jumps. Untrained healthy males took part in both experiments within the study. Subjects (n=13) had to perform maximal veloergometric effort with different resistance (3% and 10% of their own weight) for 5 seconds during first test. Then they performed passive warming up and repeated the test. Maximal motion frequency and power output were determined. Other subjects (n=14) had to perform maximal single jumps (one with squat and one without) during second test. Then they performed passive warming up and repeated the test. Maximal set off speed, strength, power output and jump height were determined. Maximal motion frequency and maximal power output after passive warming up in veloergometric test were significantly (p<0, 05) greater than before it. Maximal set off speed after passive warming up in jumping test was significantly (p<0, 05) greater, but maximal set off strength did not differ significantly performing both types of jumps. However jump height significantly increased in both cases. In conclusion, the results indicate that in untrained subjects, passive warming up improves muscles’ power output in both experiments. Another conclusion is that passive warming up has much greater effect on contraction speed than on muscles’ strength.
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ARAÚJO, Suélio da Silva. "Influência do tipo de medição na determinação do módulo estático de elasticidade do concreto." Universidade Federal de Goiás, 2011. http://repositorio.bc.ufg.br/tede/handle/tde/658.
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Previous issue date: 2011-08-15The knowledge of the compressive strength and static modulus of elasticity is fundamental to the study of deformations of concrete, since deformations can cause cracks that compromise both the structural behavior of the element and serve as an entry to deleterious agents. For purposes of correlating values of compressive strength and static modulus of elasticity of concrete, cylinders were cast with different strengths, different types of strain measurements were taken, different specimen sizes and the loading speed of the testing machine. The specimens were tested at the age of 28 days to determine the compressive strength and static module of elasticity according to ABNT NBR 8522:2008, using different types of strain measurement devices: two mechanical dial indicators, surface bonded strain gages, clip gauges and LVDT (Linear Variable Differential Transducer). Two hundred and fifty eight specimens were cast with dimensions 150 mm x 300 mm and 100 mm x 200 mm using conventional normal strength concrete (NC - Class C30) and high strength concrete (HSC - Class C60). The experimental program was divided into two stages. First the static modulus of elasticity of concrete was measured to evaluate the accuracy of the method using different measuring devices and the accuracy of the method to a loading speed of 0.6 MPa/s. Then, the modulus of elasticity using different deformation measuring devices at a loading speed of 0.3 MPa/s and 0.6 MPa/s was measured. As for concrete NC and HSC, it was found that the specimens 100 mm x 200 mm obtained higher dispersion in relation to 150 mm x 300 mm specimens. In the first stage of the research, 100 mm x 200 mm specimens showed a higher dispersion when using mechanical dial gages and LVDT. The 150 mm x 300 mm NC class C30 specimens showed greater dispersion when using in mechanical dial gages and external strain gages. However, the HSC showed higher dispersion when mechanical dial gages and LVDT were used. In both concretes tested, the mechanical dial gages showed greater dispersion. In the second stage of the research, 150 mm x 300 mm specimens tested at the loading speed of 0.3 MPa/s showed greater dispersion when electrical strain gages and clip gauges were used. The 150 mm x 300 mm specimens tested at loading speed of 0.6 MPa/s showed greater dispersion when electrical strain gages and mechanical dial gages were used.
O conhecimento da resistência à compressão e do módulo estático de elasticidade é fundamental para o estudo das deformações do concreto, uma vez que as deformações podem gerar fissuras capazes de comprometer tanto o comportamento estrutural do elemento de concreto, como servir de caminho de entrada aos agentes deletérios. Não só fissuras, mas também deformações excessivas. Para fins de correlação de valores de resistência à compressão e módulo estático de elasticidade do concreto, foram moldados corpos-de-prova variando-se a classe do concreto, o tipo de medidores de deformação, a dimensão do corpo-de-prova e a velocidade de carregamento da máquina de ensaio. Os corpos-de-prova foram ensaiados na idade de 28 dias para determinação da resistência à compressão e do módulo estático de elasticidade, normalizado pela ABNT NBR 8522:2008, utilizando-se diferentes tipos de medidores de deformação, a saber: compressômetro mecânico com dois relógios comparadores acoplados, extensômetro elétrico resistivo de colagem superficial ( strain gage ), extensômetro elétrico resistivo de fixação externa ( clip gage ) e LVDT (Transdutor Diferencial de Variação Linear). Foram moldados 258 corpos-de-prova com dimensões 150 mm x 300 mm e 100 mm x 200 mm utilizando concreto convencional de resistência normal (CC Classe C30) e concreto de alta resistência (CAR Classe C60). O programa experimental foi dividido em duas etapas: a primeira contemplou o estudo do módulo estático de elasticidade do concreto para avaliação da precisão do método utilizando diferentes medidores de deformação e da acurácia do método com velocidade de carregamento e descarregamento da máquina de ensaio em um nível: 0,6 MPa/s. A segunda etapa contemplou o estudo de determinação do módulo estático de elasticidade utilizando diferentes medidores de deformação com velocidade de carregamento e descarregamento da máquina de ensaio em dois níveis: 0,3 MPa/s e 0,6 MPa/s. Quanto ao concreto Classe C30 e CAR, verificou-se que os corpos-de-prova de dimensão 100 mm x 200 mm apresentaram maior dispersão em relação aos corpos-de-prova de dimensão 150 mm x 300 mm. Na primeira etapa da pesquisa, quanto à dimensão 100 mm x 200 mm, verificou-se que o concreto Classe C30 e o concreto de alta resistência (CAR) apresentou maior dispersão nos medidores de deformação compressômetro mecânico e LVDT. Quanto à dimensão 150 mm x 300 mm, verificou-se que o concreto Classe C30 apresentou maior dispersão nos medidores de deformação compressômetro mecânico e extensômetro elétrico de fixação externa. Já no concreto de alta resistência (CAR) apresentou maior dispersão nos medidores de deformação compressômetro mecânico e LVDT. Em ambas as classes de concreto ensaiadas, o medidor de deformação compressômetro mecânico apresentou maior dispersão. Na segunda etapa da pesquisa, quanto à dimensão 150 mm x 300 mm ensaiada com velocidade de carregamento e descarregamento da máquina de ensaio de 0,3 MPa/s, verificou-se que apresentou maior dispersão nos medidores de deformação extensômetro elétrico de colagem superficial e extensômetro elétrico de fixação externa. Quanto à dimensão 150 mm x 300 mm ensaiada com velocidade de carregamento e descarregamento da máquina de ensaio de 0,6 MPa/s, verificou-se que apresentou maior dispersão nos medidores de deformação extensômetro elétrico de colagem superficial e compressômetro mecânico.
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Lee, Trevor J. "Investigation of ASTM E 238 Bearing Pin Properties for Various Aerospace Alloys." DigitalCommons@CalPoly, 2013. https://digitalcommons.calpoly.edu/theses/1074.
Full textAbstract:
Aircraft are often designed with numbers determined by testing in a lab, rather than by repeatedly building prototypes. These lab tests conform to testing specifications so that the numbers can be compared between manufacturers, suppliers, and lab technicians. One such specification is ASTM specification E238 – 84(08), and it is used to determine important properties of a bearing pin joint like hinges, bolt holes, and rivet joints. The properties determined from this fastener-through-plate method are bearing strength, bearing yield strength, and bearing stiffness.
Adhering to the methods outlined in ASTM E238, a study was performed, looking at the effects that plate material, fastener used, fastener lubrication, and plate hole preparation method (whether drilled and reamed or just drilled) have on the three bearing joint properties. The plate materials used were Al 7050 – T7451, Ti – 6Al – 4V (mill annealed), and PH13 – 8Mo – H1000. The fasteners were Ti – 6Al – 4V screws, coated A286 screws, and high speed steel (HSS) pins used as a control. Lubrication was tested using a corrosion inhibitor, PR – 1776M B – 2 from PRC – DeSoto, on the fastener or leaving the fastener uncoated. The HSS pins were always tested in the uncoated condition. 54 runs were performed, as outlined by a D-optimal design of experiment.
It was discovered from the statistical analysis of the results via ANOVA that both the plate material used and the pin material, whether a screw or a pin, had a significant effect on the bearing strength, bearing yield strength, and bearing stiffness. The interaction between the two factors was also significant on all responses but the bearing stiffness. PH13 – 8Mo – H1000 plates seemed to perform best on average, followed by Ti – 6Al – 4V plates, then Al 7050 – T7451 plates. PH13 – 8Mo – H1000 and Ti – 6Al – 4V plates had similar bearing strength and bearing yield strength averages with the HSS control pins being used, which had the highest mean values for a given plate and fastener. The Ti – 6Al – 4V and A286 screws behaved and performed statistically similar in most cases, except when hole preparation method was take into account. The Ti – 6Al – 4V screws performed better when the hole was drilled and reamed, while the coated A286 screws performed better when the hole was drilled only. All screws had lower resulting bearing properties than the HSS control pins.
It was also found that ASTM specification E238 – 84(08) is a precise test method, since the method could be performed repeatably and reliably with no missing data points. Therefore, this ASTM testing method is reasonable for determining bearing properties, which can then be used to design aircraft.