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1
Saravanan, Indrajeet. "Exploring Computational Sprinting in New Domains". The Ohio State University, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=osu1555586869706602.
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2
Stokes, Keith. "Human growth hormone responses to sprinting". Thesis, Loughborough University, 2001. https://dspace.lboro.ac.uk/2134/34383.
Testo completoAbstract (sommario):
A number of studies have shown exercise to stimulate human growth hormone (hGH) secretion, although most of these have considered prolonged submaximal or resistance exercise. Only a few have studied maximal sprint exercise, and these studies have demonstrated considerably elevated circulating hGH concentrations during recovery. However, there is little agreement in the literature regarding the regulation of hGH secretion during and after exercise. This thesis describes a series of experiments considering the hGH response to sprint exercise, with the intention of gaining a better understanding of some of the mechanisms involved in regulating the exercise-induced hGH release.
3
Bezodis, Ian Nicholas. "Biomechanical performance variation in maximum velocity sprinting". Thesis, University of Bath, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.432390.
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4
Sinden, Sean. "Does salbutamol improve sprinting performance following endurance cycling?" Thesis, University of British Columbia, 2015. http://hdl.handle.net/2429/55863.
Testo completoAbstract (sommario):
Salbutamol, an inhaled asthma medication, may have a number of extra-pulmonary effects throughout the body that may result in an ergogenic benefit during exercise.
Purpose: To investigate the ergogenic effects of high-dose inhaled salbutamol on sprint performance following a prolonged, individualized, steady-state exercise bout; secondarily, to identify the systemic effects of salbutamol during steady-state exercise that might explain such an ergogenic finding.
Methods: Using a eucapnic voluntary hyperpnoea test, ten male and ten female cyclists were tested for exercise-induced bronchoconstriction (EIB). Using a crossover design, participants inhaled either placebo or 1600g of salbutamol and subsequently completed two 75-minute constant power cycling bouts immediately followed by a 30-second Wingate test. Primary outcomes were those collected during the Wingate test: peak and mean power. Lactate, perceived exertion, ventilatory, and gas exchange measurements were collected throughout the steady-state bout. A repeated-measures ANOVA was utilized to assess the effects of sex, EIB status, and salbutamol on performance outcomes.
Results: Lung function was improved following salbutamol inhalation (M = 8.3%, SD = 1.0%) compared to placebo (M = 1.0%, SD = 5.6%). The differences in peak and mean power between the salbutamol and placebo conditions were not found to be statistically significant. During the 75-minute endurance bout, carbohydrate utilization, heart rate, and minute ventilation were increased while ventilatory efficiency was decreased. In general, the effects of salbutamol were more pronounced in women relative to men, while no impactful differences were found as a function of EIB status. Conclusion: Despite inducing a possible increase in carbohydrate metabolism, salbutamol inhalation did not cause a significant increase in peak or mean power during a 30-second Wingate test.Education, Faculty of
Kinesiology, School of
Graduate
5
Wragg, Chris. "Trunk muscle fatigue in soccer-specific repeated sprinting". Thesis, University of Brighton, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.251744.
Testo completo
6
Andrews, Barry S. "Sprinting kinematics of athletes with selected physical disabilities". Thesis, Stellenbosch : Stellenbosch University, 2014. http://hdl.handle.net/10019.1/86436.
Testo completoAbstract (sommario):
Thesis (PhD(Sport Sc))--Stellenbosch University, 2014.ENGLISH ABSTRACT: The purpose of this research was to gain insight into the sprinting of athletes with selected physical disabilities. The sprint performances of four Paralympic athletes (T43, T13, T37 and T38 classifications) were analysed in terms of variability in the biomechanics of their set position and in the kinematics of the initial acceleration phase and the maximal acceleration phase of their 100m sprints. The athletes also reported their perceptions about the potential of a rhythm training programme to influence their sprinting. A case study approach was used. Sprint kinematics were video-recorded four times over the training year. DartFish ProSuite software supported the digital tagging of anatomical landmarks and the calculation of the biomechanical features of the set position as well as the kinematics of each athlete. A subjective log was used to gather their perceptions about the rhythm training programme. There was variability in all aspects for all four Paralympic athletes. This should encourage coaches to help athletes find optimal kinematics in relation to their disability, rather than trying to coach them to a set template of an ideal form. Based on the kinematic data collected over all four test sessions, it appears that a coaching focus on stride length was the key to faster sprinting for this T43 (amputee) athlete. A coaching focus on stride frequency (once optimal stride length had been discovered) was the key for the T13 sprinter (visually impaired), and a coaching focus on stride frequency was the key to faster sprinting for both the T37 and T38 athletes (cerebral palsy). Although all of the athletes enjoyed the rhythm training programme, only the least experienced athlete (T38) reported that he would like to continue with this form of training.
AFRIKAANSE OPSOMMING: Die doel van hierdie navorsing was om insig rakende die naellooptegnieke van atlete met geselekteerde fisiese gestremdhede te verky. Die naellooptegnieke van vier Paralimpiese atlete (T43, T13, T37 en T38 klassifikasies) is ontleed. Die ontleding is gedoen met betrekking tot die veranderlikheid in biomeganika tydens hul gereedheidsposisies in die wegspringblokke asook in die kinematika van die aanvanklike versnellingsfase en die maksimale versnellingsfase gedurende hul 100m naelloopitems. Die atlete het ook hul persepsies rakende ’n ritmiese oefenprogram wat potensieël hul naellope kon beïnvloed gerapporteer. ’n Gevallestudiebenadering is gebruik. Beeldmateriaal van naelloopkinematika is vier keer gedurende die oefenjaar vasgelê. “DartFish ProSuite” sagteware het die digitale kodering van anatomiese punte ondersteun asook die berekening van biomeganiese eienskappe gedurende die gereedheidsposisie en die kinematika van elke atlete gefasiliteer. Daar is op ’n subjektiewe basis boekgehou van die atlete se persepsies rakende die ritmiese oefenprogram. Daar was wisselvalligheid in alle aspekte met betrekking tot al vier Paralimpiese atlete. Dit behoort as aanmoeding vir afrigters te dien om atlete te help om optimale kinematika in verband met hul gestremdheid te vind, eerder as om die atlete volgens ’n vaste templaat of ideale vorm te probeer afrig. Volgens die kinematiese data wat oor die loop van al vier toetsingsessies ingesamel is blyk dit asof ’n afrigtingsfokus op treëlengte die sleutel tot vinniger naellope vir die T43- atleet (amputasie) was. ’n Afrigtingsfokus op treëfrekwensie (nadat optimale treëlengte bewerkstellig is) was die sleutel vir die T13-atleet (visueel gestremd) en ’n afrigtingsfokus op treëfrekwensie was die sleutel tot vinniger naellope vir beide die T37- en T38-atlete (serebrale gestremdheid). Alhoewel al die atlete die ritmiese oefenprogram geniet het, het slegs die mees onervare atleet (T38) aangedui dat hy met hierdie vorm van oefening sou wou aanhou.
7
Duncan, Laura C. "Interval Sprinting: Impact on Reading Fluency and Self-efficacy". TopSCHOLAR®, 2018. https://digitalcommons.wku.edu/theses/3049.
Testo completoAbstract (sommario):
Reading fluency is the ability to decode connected text with accuracy and speed (Archer, Gleason, & Vachon, 2003; Daly, Neugebauer, Chafouleas, & Skinner, 2015), and is generally measured by how many words a student can read in a minute. Selfefficacy is the judgment people make about their own performance levels for specific abilities, which affects their motivation and behaviors concerning those abilities (Bandura, 1977). It is unknown if repeated reading or interval sprinting reading interventions have an effect on reading self-efficacy. Two third-grade students with low reading fluency participated in an alternate treatment design, using repeated reading and interval sprinting reading interventions. After each session, reading self-efficacy was assessed using the Children’s Intervention Rating Profile (CIRP; Witt & Elliot, 1985). Results indicated that neither student’s reading fluency increased as expected with single session dosage, but their reading self-efficacy did increase for both the repeated reading and interval sprinting interventions. Student 2 demonstrated an increase in reading fluency and reading self-efficacy following the repeated reading intervention when the intervention dosage was increased. Both students reported increases in reading self-efficacy, even when their reading fluency did not increase, suggesting these interventions may provide benefits beyond simply increasing the number of words a student can read in one minute
8
Hansen, Keir. "A kinematic analysis of acute and longitudinal adaptions to resisted sprinting submitted to Auckland University of Technology for the degree of Master of Health Science, July 2002". Full thesis. Abstract, 2002.
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9
Maulder, Peter Scott. "The physical power pre-requisites and acute effects of resisted sled loading on sprint running kinematics of the early acceleration phase from starting blocks this thesis is presented in partial fulfillment of the requirements for the Master of Health Science degree at Auckland University of Technology, January 31st 2005 /". Full thesis. Abstract, 2005. http://puka2.aut.ac.nz/ait/theses/MaulderP.pdf.
Testo completoAbstract (sommario):
Thesis (MHSc--Health Science) -- Auckland University of Technology, 2005.Supervisors: Mr Justin W L Keogh, Dr Elizabeth J Bradshaw. Also held in print (143 leaves, col. ill. 30 cm.) in Akoranga Theses Collection (T 612.76 MAU)
10
Kawamori, Naoki. "Sprint acceleration performance in team sports : biomechanical characteristics and training methods". Thesis, Edith Cowan University, Research Online, Perth, Western Australia, 2008. https://ro.ecu.edu.au/theses/224.
Testo completoAbstract (sommario):
Sprinting is a fundamental activity in many team sports such as soccer, rugby, football, field hockey, and basketball. Specifically, the ability to rapidly increase sprint running velocity over short distances, which is often referrcd to as sprint acceleration ability, is of major importance to team-sport athletes since sprint efforts during team-sport matches are typically of short duration (e.g., 10-20 m, 2-3 s). Biomechanical characteristics of the acceleration phase of sprinting has previously been studied in track sprinters from a block start, but there is a dearth of research exploring tile biomechanieal charactcristics of sprint acceleration in team-sport athletes from starting positions that are specific to team-sport match situations (e.g., standing start). In addition, resisted sprint training such as weighted sled towing is a popular training modality that athletes often use in an effort to improve sprint acceleration ability, but its use is largely based on choaches' observation and lacks experimental evidence. In particular, the optimal training load for resisted sprint training is currently unknown. This thesis explored to fill the research gap in such areas.
11
Jenkins, Karen M. "The effect of wearing strength shoes during plyometric training on vertical jump performance". Thesis, This resource online, 1993. http://scholar.lib.vt.edu/theses/available/etd-06232009-063100/.
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12
Lane, William Todd. "Effects of dynamic, static stretch, and proprioceptive neuromuscular facilitation on running velocity, step length, and step rate". Click here to access thesis, 2005. http://www.georgiasouthern.edu/etd/archive/fall2005/todd%5Fw%5Flane/lane%5Ftodd%5Fw%5F200508%5FMS.pdf.
Testo completoAbstract (sommario):
Thesis (M.S.)--Georgia Southern University, 2005."A thesis submitted to the Graduate Faculty of Georgia Southern University in partial fulfillment of the requirements for the degree Master of Science in the Department of Public Health" ETD. Includes bibliographical references (p. 37-41) and appendices.
13
Kivi, Derek M. R. "A kinematic comparison of the running A and B drills with sprinting". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/tape17/PQDD_0006/MQ32155.pdf.
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14
Daly, Colm. "Biomechanical factors associated with previous hamstring injury in high level sprinting athletes". Thesis, Queen Mary, University of London, 2017. http://qmro.qmul.ac.uk/xmlui/handle/123456789/24590.
Testo completoAbstract (sommario):
Hamstring injury is common in sprinting sports and injury recurrence remains a major concern. The aim of this thesis is to explore the biomechanical characteristics of athletes following sprint related hamstring injury. We conducted 1) An examination of already published research on biomechanical deficits following hamstring injury in athletes who had returned to sport by means of a systematic review and meta-analysis; 2) A detailed examination of sprinting following hamstring injury in athletes who had returned to sport muscle activity using 3D motion capture and surface EMG; 3) An examination of high intensity eccentric loading performance in previously injured athletes using low density, high surface area surface EMG and measures of force; 4) An analysis of hamstring muscle recovery until return to sport following hamstring injury using low density, high surface area surface EMG and measures of force via case reports in two elite athletes. Previous research indicates that athletes who had returned to sport following hamstring injury continue to display deficits in force production, especially during slow eccentric contractions. The observational studies indicate that athletes run with significantly asymmetric movements about the pelvis and hip that would place their hamstrings under increased length during the terminal swing phase of sprinting. Furthermore, significant alterations in late swing EMG ratios suggest relatively reduced activity in the previously injured biceps femoris. Spatial activation of the hamstring appears altered in previously injured athletes, with reduced relative activation of the proximal muscle and reduced median frequency values in the medial muscle compared to control limbs. Asymmetries in activation patterns are also noted in the pre-return to sport phase. Previous hamstring injury is associated with significant alterations in force production, movement symmetry and muscle activation patterns following return to sport highlighting the complexity of this injury and the need for advanced rehabilitation screening approaches.
15
Cheetham, Mary E. "Effect of training on the metabolic responses to treadmill sprinting in man". Thesis, Loughborough University, 1987. https://dspace.lboro.ac.uk/2134/33031.
Testo completoAbstract (sommario):
Whilst the metabolic responses to submaximal exercise have been relatively well documented little information is available relating to maximal exercise. Thus, the purpose of this study was to examine the physiological and metabolic responses to sprint running exercise, with the objective being to contribute to both the understanding of those factors which underlie or determine performance and also to the current understanding of intermediate metabolism in man during exercise. A laboratory-based running test was developed using a non-motorised treadmill, which allowed the simultaneous examination of performance and the associated changes in muscle metabolism during sprint exercise. This test was sensitive enough to monitor the differences in performance between individuals with varying training backgrounds and to monitor the changes in performance within the same group of individuals resulting from a short period of training.
16
Shorten, James. "Relationships between sprint performance, power output and fatigue". Thesis, This resource online, 1991. http://scholar.lib.vt.edu/theses/available/etd-03022010-020148/.
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17
Opheim, Maximilian Nicholas. "Effect of Capsaicin Supplementation on Performance of and Physiological Response to Repeated Sprinting". Thesis, Virginia Tech, 2010. http://hdl.handle.net/10919/41217.
Testo completoAbstract (sommario):
Aim: Fatigue during team sports requiring multiple sprints can result from the combined effects of metabolic, mechanical, neurological, and immune factors. The purpose of this study was to investigate the influence of capsaicin on performance of and the physiological response to an exercise test simulating the fitness demands of team sport game conditions. Methods: This study was a placebo-controlled, crossover design. Nineteen healthy male experienced athletes age 18-30 yr consumed either 3 g/d cayenne (25.8 mg/d capsaicin) or placebo for 1 wk. Directly following the supplementation period, they completed a repeated sprint test consisting of 15 30 m maximal effort sprints on 35 s intervals. Sprint times were recorded via electronic dual-beam timing system. Fasted blood draws for interleukin-6 (IL-6) were taken at baseline prior to supplementation, 45-min pretest, and immediately post test. Heart rate (HR), blood pressure (BP), rate of perceived exertion (RPE), muscle soreness (MS), and gastrointestinal distress (GD) were measured 1-min pretest, during, posttest, and 1-min posttest. MS was also measured for 3 d posttest. Results: Relative to the placebo, capsaicin significantly reduced maximum HR by 9.3%, total average HR by 8.5%, and sprinting average HR by 6.0% (P<0.05). Capsaicin caused GD of at least 2/5 in 24.5% of subjects. There was no difference between treatments in fastest or mean sprint time, fatigue, percent change or difference in IL-6, BP, RPE, sprint or posttest MS. Conclusion: Capsaicin did not influence repeated sprint performance or the inflammatory response, but reduced HR during intense activity and causes substantial GD.Master of Science
18
Buckley, John G. "Variable speed walking and running in physically active lower-limb amputees : gait biomechanics and prosthetic design influences". Thesis, Manchester Metropolitan University, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.343457.
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Maxwell, Neil S. "Sprint running in man and the effects of performing supramaximal exercise under different conditions of stress". Thesis, University of Strathclyde, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.367034.
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20
Sides, D. L. "Kinematics and kinetics of maximal velocity sprinting and specificity of training in elite athletes". Thesis, University of Salford, 2015. http://usir.salford.ac.uk/34332/.
Testo completoAbstract (sommario):
Maximal velocity sprinting has been studied extensively from a biomechanical standpoint, however little is known of the biomechanics characteristics at sprint velocities that typify elite athletic performance, due to the difficulties in accessing such athletes and collecting data within a competitive environment. Research has investigated the optimal training to achieve such velocities, with a focus on the specificity of training principle. However the specificity of the common training methods of elite sprinters is yet to be investigated from a biomechanical perspective. Investigations of ten international level sprinters in a competition environment revealed the kinematic variables which characterise sprint velocities exceeding 10.0m/s. Elite sprinters minimised the touchdown distance and knee flexion during ground contact, and terminated stance prior to full extension of the hip and knee. An additional kinetic analysis on six elite male sprinters revealed a greater hip angle at touchdown and higher maximum and average hip velocities in swing were associated with lower peak braking forces. Reduced hip and knee extension at toe-off along with a greater degree of maximum hip flexion were associated with a higher vertical impulse. A movement specificity framework was developed to quantify the holistic specificity of training methods based on biomechanical movement principles. The Bulgarian split squat drop had a high specificity to maximal velocity sprinting with respect to the loading principles. Running drills were highly specific based on coordination principles, in particular the leg extension velocities in the late phases of stance. The kinematic and kinetic models can be used by coaches to evaluate individual athletes against true elite sprinting, whilst the movement specificity framework can be utilised to design and maximise the specificity of sprint training programmes.
21
Bezodis, Neil. "Biomechanical investigations of sprint start technique and performance". Thesis, University of Bath, 2009. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.512297.
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22
O'Grady, Mathew. "Manipulating a conditioning activity to enhance potentiation and its application to jumping and sprinting performance". Thesis, Federtion University Australia, 2017. http://researchonline.federation.edu.au/vital/access/HandleResolver/1959.17/165480.
Testo completoAbstract (sommario):
Post-activation potentiation (PAP) is the phenomenon where contractile history of a muscle may acutely increase voluntary performance of future contractions that are biomechanically similar (72). In order to exploit the PAP phenomenon, a conditioning activity (CA) is performed to enhance the performance of a subsequent skill. Throughout the literature, a common example of a CA is sets of heavy-loaded squats in order to potentiate subsequent jumping (31,33,39,57,83,116,151,163) or sprinting performance (15,28,39,99). Post-activation potentiation can be used either in a warm-up to acutely enhance performance for competition, or used within a resistance training session to enhance speed-strength, with the intention of producing a greater training stimulus for chronic adaptations. The major issue with the PAP literature is the inconsistent results from study to study. There are many examples within the research that show the positive effects of PAP (44,54,57,62,83,102,133,163), whilst many others have failed to find any increase in performance (42,47,56,81,112,123,141). The results have been inconsistent as the methodology between studies has varied dramatically. These differences include the warm-up used prior to testing sessions, changes in the type of CA (30,54,163), the intensity or load of the CA (19,21,33) and the rest period allocated between the CA and the performance of the skill. Furthermore, it seems that certain individuals respond better to a CA, with most of the literature suggesting that participant strength has a positive correlation with a potentiating response (15,31,44,116,128,129,163). Due to the vast differences in methodologies used throughout the potentiation literature, it is hard for coaches to identify the best practice in order to elicit a positive potentiating effect. Therefore, four studies were designed to address these current gaps within the potentiation literature in order to establish the best methodology to elicit a potentiating response. The first study sought to investigate whether a heavy half-squat CA could further improve jumping after an individualised optimal warm-up. As many of the warm-ups used prior to the baseline measurement in the potentiation research have been insufficient (30,44,69,71,88,102,111,115,140,143,158), it is plausible to suggest that improvements after a CA could be due to general mechanisms of a warm-up, rather than PAP. To investigate this, participants performed six different volumes of warm-ups on six separate days, followed by CMJ and DJ testing. After each participant completed the six warm-ups, their individual optimum warm-up was identified as the warm-up that produced the greatest CMJ relative peak power (RPP). On two separate sessions, a CA of four half-squats at a 5RM load was then added to each individual’s optimum warm-up and a sub-optimum warm-up. Countermovement jump tests were performed before the CA (pre) and then four and eight minutes after the CA. Drop jump testing was performed before the CA (pre) and then six and 10 minutes after the CA. When examining each post-test separately, no improvements in CMJ performance were identified. Furthermore, for both the optimum and sub-optimum warm-up conditions, DJ performance significantly decreased at all post-tests (p < 0.05). When each individuals best recovery period was considered (post-best), both the maximum and mean CMJ jump height significantly increased above baseline measures for the optimum warm-up condition. No other CMJ or DJ variable displayed any significant change after the addition of the CA for either condition. As significant increases in CMJ jump height were identified, the four half-squat CA with a 5RM load was used in the next investigation. Although each individual’s optimum warm-up volume varied, the moderate warm-up volume produced sufficient CMJ performance for all individuals. Considering the time required identifying each individuals optimum warm-up, the moderate warm-up was deemed sufficient and was used for the following studies. The second study of this thesis investigated the acute response of two different CA strategies. Both CAs included four half squats at a 5RM load, however, in one condition participants were instructed to perform the squat in a controlled manner, whilst in the second condition, they were instructed to lift the bar as fast as possible without losing contact with the ground. At any post-time (including post-best), no significant improvement were identified for any CMJ variable in either condition. Furthermore, DJ performance significantly decreased at all post-tests for the explosive CA condition. Although no significant improvements were identified, when each individual’s optimum recovery period was considered, CMJ jump height increased by 2.6% in the explosive CA condition, as opposed to 0.9% in the controlled CA condition. Because of this difference within the means of each condition, for the future studies throughout this thesis, participants were instructed to lift the bar as fast as possible during a heavy half-squat CA. The third study of this thesis compared different volumes of plyometric CAs (rebound jumps) to a CA involving heavy half-squats and assessed the effect each had on potentiating CMJ and sprinting performance. Past research had often used small amounts of plyometric contacts to potentiate future contractions (23,30,143,146,151), however, due to their short duration; they were often not successful in improving performance. For one condition, this study increased the repetitions of plyometric contacts in the CA, so that its duration matched the time under tension exhibited by the four half-squats with a 5RM load. Furthermore, two other plyometric CA conditions were included; one that matched half of the time under tension of the half-squats and one that involved only four repetitions of the rebound jump (match the amount of repetitions of the half-squat). No CA (plyometric or half-squat) displayed statistical significant improvements in CMJ or sprint performance at any post-test interval. For CMJ performance, although it did not significantly improve performance, generally the heavy half-squat CA had smaller decrements in performance than the plyometric CAs, hence the final investigation of this thesis focussed upon different heavy dynamic CAs in order to potentiate CMJ performance. The final study of this thesis firstly aimed to investigate the effect of three different types of half-squat CAs had on potentiating CMJ performance. This study also aimed to explore why certain individuals respond positively to a CA, whilst others respond in a negative manner. At the beginning of this study, participants completed a number of fitness performance tests, to assess each individual’s performance. Participants then assessed the effect of three different CAs on CMJ performance. These CAs included three repetitions of the half-squat with a 3RM load (3 @ 3RM), four repetitions with a 5RM load (4 @ 5RM) and then five repetitions with a 5RM load (5 @ 5RM). In terms of the entire population of the study, after each of the CAs, post-CMJ performance typically decreased across all rest periods, whilst any improvement in particular CMJ variables were considered to only be trivial in terms of effect size magnitudes. Despite this, multiple statistically significant positive correlations were evident between particular fitness qualities (absolute strength, CMJ RPP and aerobic capacity) and the change scores between pre and post-best CMJ performance after certain CAs. Therefore, the participants were median split in terms of each of the following fitness qualities to assess the relationship each quality has on potentiating CMJ performance. When the population was split in terms of absolute strength, the stronger participants significantly improved CMJ performance at their best recovery period after the performance of the 5 @ 5RM CA (three out of the four CMJ variables assessed significantly improved), whilst the weaker individuals showed no significant improvements. A similar trend was exhibited when the population was split in terms of CMJ RPP, with the more powerful individuals improving by small to moderate effect size magnitudes after the 5 @ 5RM CA, whilst the less powerful group did not. From the studies presented in the thesis, it can be concluded that certain recreationally resistance trained males can acutely enhance CMJ performance with the use of a heavy dynamic CA, even after pre-test performance has been optimised by a general warm-up. The optimum recovery period for the individual does need to be considered, as individuals require different amounts of rest to allow for an improvement in performance. Furthermore, the individual needs to have sufficient strength of the lower limbs in order to improve future contractions via the use of the heavy dynamic CA, as individuals with less strength do not improve post-CMJ performance after a CA. In terms of the type of CA used, heavy half-squat seem to be more effective than rebound jumps in order to potentiate CMJ performance. Furthermore, five repetitions with a 5RM load seems more effective than heavier CAs (3 @ 3RM) or ones that have less repetitions (4 @ 5RM) for this particular population.Doctor of Philosophy
23
Madon, Mohd Sani. "Preparatory strategies for optimising an all-out sprint effort". University of Western Australia. School of Human Movement and Exercise Science, 2007. http://theses.library.uwa.edu.au/adt-WU2007.0109.
Testo completoAbstract (sommario):
[Truncated abstract] The inclusion of a warm-up in the form of prior exercise (PE) is generally advocated as a preparatory strategy of choice to improve sprint performance. Although there is evidence that both increasing muscle temperature and mobilising the cardiorespiratory system prior to exercise contribute largely to the benefit of PE on sprint performance, their relative importance is unknown. Another important question relates to situations where an athlete has to engage in a sprint shortly after one or several earlier sprints. Under these conditions, is engaging in mild exercise also the most effective preparatory strategy to adopt prior to sprinting when performed after a previous sprint(s)? It was the primary aim of this thesis to address these questions. Firstly, we hypothesised that there is a temporal shift in the mechanisms responsible for the effect of PE on power output during a maximal sprint effort, with temperature-dependent mechanisms playing a more important role at the onset of the sprint and mobilisation of the cardiorespiratory system playing a more important role later. To test this hypothesis, we compared the responses of a 30-s sprint to different PE protocols designed to control for either muscle temperature or pre-exercise VO2. ... A group of trained athletes was subjected to four consecutive bouts of 30-s sprint, each separated by 20 min of either active recovery at 40% VO2 peak or passive recovery. Our results show that PP, MP-20 and MP-10 did not fall between the first and last sprints, and were not affected by active recovery. In contrast, we found that MP10 and MP30 decrease significantly between the first and last sprint of the passive recovery trial, but not when active recovery is performed between consecutive sprints. Finally, this study also showed that the fall in mean power associated with repeated 30-s sprints in the passive recovery trial resulted primarily from a fall in early, but not late power output. These findings show that the early and late mean power output of repeated sprints respond differently to active and passive recovery, with the decrease in total mean power with repeated 30-s sprints resulting primarily from a fall in early as opposed to either late power output or peak power, thus highlighting the benefit of active recovery as a favourable preparatory strategy for the performance of repeated sprints of short (<10s) or longer duration (<30s), but not for repeated peak power.
24
Moir, Gavin. "An exploration of the effect of resistance training on performance and co-ordination during accelerative sprinting". Thesis, University of Edinburgh, 2004. http://hdl.handle.net/1842/24990.
Testo completoAbstract (sommario):
The principal aim of the present thesis was to investigate the effect of increasing muscular strength on the co-ordination of movement during accelerative sprinting. Physically active males fro the University of Edinburgh participated in an 8-week resistance training study. Pre and post-training measures of 10 m and 20 m sprint time, maximum strength and explosive strength were taken. The first 3 strides of the 20 m sprint were videoed for further analysis. Changes in co-ordination were assessed using phase-plane diagrams and continuous relative phase (CRP) measures. The resistance training intervention resulted in a significant increase in maximum and explosive strength immediately following the training period, but sprint times were not improved. Increases in the vertical impulse, with concomitant decreases in the horizontal impulse were recorded following the training period. These changes caused a reduction in stride frequency. Although the resistance training increased muscular strength the control of the orientation of the ground reaction force with respect to the centre of mass (CoM), which has been identified as a specific constraint associated with the stance period of accelerative sprinting, was not adapted. The result of the present thesis demonstrates that an 8-week resistance training intervention increases muscular strength but does not improve accelerative sprint performance immediately following the training period. Sprint running performance is affected by the complex interaction of constraints associated with the task and the physical characteristics of the performer. Muscular strength has been identified as a characteristic that constrains the co-ordination of multi-joint movements. Considering the effect of resistance training on the control and co-ordination of multi-joint movements provides further insight into the effectiveness of potential training interventions, such as resistance training, and provides information for coaches to develop strategies to expedite the transfer of strength to accelerative sprinting.
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Vance, Denice A. "The Effects of Carbohydrate, Protein, and Carbohydrate with Protein Solutions on 200-Meter Sprint Speed". Digital Archive @ GSU, 2010. http://digitalarchive.gsu.edu/nutrition_theses/24.
Testo completoAbstract (sommario):
Purpose: To investigate the differential effects of solutions providing varying concentrations of carbohydrate and/or protein ingested between 200-meter sprints on sprint time. Subjects: Recruitment was from the Georgia State University track and field team. Methods: The study protocol was approved by the Georgia State University IRB. Ten subjects, 18 to 21 years of age, consented to be included in the study. Nine subjects (7 females; 2 males) completed trial 1, six subjects (5 females; 1 male) completed trial 2, and three subjects (2 females; 1 male) completed the final trial. Each trial consisted of a 200-meter sprint followed by the immediate ingestion of a post-exercise recovery beverage within the first fifteen minutes of a one-hour recovery period. Following the one-hour of recovery, subjects sprinted a second 200-meter sprint. Beverage solutions were formulated to contain 1.2 g of protein (PRO), 1.2 g carbohydrate (CHO), or 1.2 g carbohydrate with protein (CHO/PRO) per kg of subject body weight. Using a single blind, non-randomized design, subjects received the same recovery beverage in each trial. Each trial consisted of either PRO (trial 1), CHO (trial 2), or CHO/PRO (trial 3), with one week separating trials. Sprint times were recorded in seconds and ten hundredths of a second using a manual, digital stopwatch. Results: During PRO, two subjects sprinted faster (x= -.25 sec), three subjects saw no change in sprint time, and four subjects sprinted slower (x= +.98 sec). During CHO, two female subjects sprinted faster between sprints (x= -.85 sec); and all other subjects (n=4) sprinted slower (x= +.73 sec). During CHO/PRO, no subjects sprinted faster from sprint 1 to sprint 2 (x= +.33 sec) Conclusions: Post-exercise nutritional supplementation effects varied among subjects, with some subjects performing better following PRO, while others experiencing improvements with CHO. In general, subjects performed better following consumption of the CHO beverage. Of those who ran faster between sprints, the CHO beverage resulted in an average improvement of -.85 sec, while the PRO beverage resulted in an average improvement of -.25 sec. On average, CHO resulted in faster 2nd sprints (x= +.20 sec) than the PRO beverage (x= +.47 sec) or the CHO/PRO beverage (x= +.33 sec). Continued research in this population is necessary for elucidation of study results. This investigation may serve as the foundation for future, related studies.
26
Haffor, Al-Said A. "Carbon dioxide storage capacity of endurance and sprint-trained athletes in exercise /". The Ohio State University, 1985. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487259125221279.
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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.
Testo completoAbstract (sommario):
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.
28
Toon, Daniel. "Design and analysis of sprint footwear to investigate the effects of longitudinal bending stiffness on sprinting performance". Thesis, Loughborough University, 2008. https://dspace.lboro.ac.uk/2134/12125.
Testo completoAbstract (sommario):
There is evidence to suggest that the bending stiffness of footwear can be adapted to influence sprinting performance. In addition, it has been suggested that to achieve maximal performance, the mechanical properties of this footwear needs customising to an individual athlete. Due to a lack of detailed biomechanical data, the influence of longitudinal bending stiffness on the dynamics of the lower extremity during sprint running remains largely unexplained and is subject to considerable speculation. Thus, the aim of this work is to develop functional sprint footwear in a range of different longitudinal bending stiffnesses in order to explore the effects on measures of sprinting performance and lower extremity dynamics. Novel mechanical test procedures were developed and benchmark properties of current commercial sprint spikes were ascertained. Bending stiffness data showed considerable variability amongst those sprint spikes aimed at athletes of a higher competitive standard, which indicates that there is no consensus regarding optimum stiffness. A kinematic analysis of barefoot and shod sprinting was undertaken to investigate the influence of sprint footwear on lower extremity kinematics. Medial and lateral sagittal plane data were collected at the start and in the acceleration (10 m) and maximal speed (50 m) phases of a 100 m distance. Metatarsophalangeal joint (MPJ) angular range and velocity were significantly reduced in sprint spikes compared to barefoot conditions and the magnitude of the controlling affect was larger at 10 m compared to 50 m. Selective laser sintering of nylon was used to produce a number of sprint shoe sole units each of different thickness. These were attached to standard uppers to produce a range of longitudinal bending stiffnesses encompassing those already commercially available. The influence of shoe stiffness on sprinting perfonnance was assessed using specific jump metrics that were selected for use based on their high correlations with sprinting perfonnance during starting and maximal speed sprinting. Results indicated that sprint shoe longitudinal bending stiffness influenced the dynamics of the lower extremity during squat and bounce drop jumps. The relationship between maximal perfonnance and shoe stiffness was specific to the jump metric; best performance was achieved in intermediate stiffness shoes for the squat jumps and high stiffness for bounce drop jumps. Six bespoke pairs of sprint shoes with bending stiffness spanning and exceeding that of current commercial sprint spikes were developed. Results showed that MPJ and ankle joint dynamics were affected by longitudinal bending stiffness during squat and bounce drop jumps. Angular velocities of the MP and ankle joints were significantly reduced with increasing longitudinal bending stiffness. For the squat jump, ankle joint moments increased with shoe longitudinal bending stiffness and reached an individually optimal level within the stiffness range. This was also the case for ankle joint power and mechanical energy. The bounce drop jump saw mechanical energy generation at the MPJ increase with shoe longitudinal bending stiffness. Different levels of longitudinal bending stiffness were required for maximal performance in each jump type. This infers that sprint shoe bending stiffness requirements may vary according to the phase of the race. Furthermore, individual responses to different stiffnesses highlighted the importance of personalising mechanical properties to the requirements of a particular athlete for maximal performance. This research has focused on the use of discrete jump metrics to assess performance and therefore future work should aim to investigate the implications of different stiffness conditions using measures of actual sprinting. Also, further detailed musculoskeletal explorations are required in order to fully understand the precise mechanism by which longitudinal bending stiffness influences performance.
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Vardaxis, Vassilios. "The mechanical power analysis of the lower limb action during the recovery phase of the sprinting stride for advanced and intermediate sprinters /". Thesis, McGill University, 1988. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=61663.
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Freeman, Brock. "The role of sprint training in hamstring strain injury prevention for field sport athletes". Thesis, Federation University Australia, 2022. http://researchonline.federation.edu.au/vital/access/HandleResolver/1959.17/185191.
Testo completoAbstract (sommario):
Hamstring strain injuries (HSI) are regularly reported as the most common injury in many field-based sports with a high-speed running (HSR) component. Typically, these injuries occur during sprinting efforts, predominantly in the Biceps Femoris Long Head (BFLH). Furthermore, the burden of HSI is amongst the highest in field sports, and the risk of recurrent injury is elevated, and inflated by age. It is of interest to managers, technical coaches, physical preparation staff and athletes to reduce the risk of sustaining a HSI. Therefore, extensive research in HSI has identified several non-modifiable and modifiable risk factors, such as eccentric hamstring strength, BFLH fascicle length, and HSR exposure. Currently, almost all interventions designed to reduce the risk of HSI have utilised resistance training or stretching interventions. This is despite the scientific literature indicating that; 1) sprinting is the most common mechanism associated with hamstring strain injury, and 2) sprinting places a far greater demand on the hamstrings than interventions that are resistance or flexibility based. Therefore, the primary aim of this thesis was to establish the role of sprint training in HSI prevention in field sport athletes. The aim of Study 1 was to understand the beliefs and practices of professional Australian Football (AF) physical performance coaches towards the training and assessment prescribed to mitigate the risk of HSI. A Delphi-validated mixed methods survey was implemented to assess the beliefs and practices of High-Performance Managers of professional AF teams. All the participants in this study reported that they believed sprinting (acceleration and maximum speed) was the most common activity associated with HSI. Similarly, all participants also indicated they performed sprint training for injury prevention purposes. However, a range of relative speeds were reported to quantify HSR, whilst a sprint was reported as 85%Vmax. Whilst respondents reported they believed that sprint training was important, one participant indicated that they felt the need to be conservative with the prescription of sprint training for fear of injury, and the consequences associated with this. Due to the identified discrepancies in speed thresholds used in practical setting (Study 1) and academic settings (Literature Review), Study 2 was designed to determine the absolute, and relative speeds associated with jogging, running, striding, near maximum sprinting, and sprinting. The secondary aim was to visually describe the gait patterns associated with HSR and sprinting. Fifteen participants completed two data collection periods, where they performed a series of run throughs at different gait patterns. These gait patterns were adapted from a review of time-motion research in field sports. The running gaits of jogging, running, striding, near-maximum sprinting, and sprinting correspond with the relative speeds of 56%Vmax, 66%Vmax, 78%Vmax, 87%Vmax, and 100%Vmax, respectively. Significant (p = 0.01) differences were observed for all variables between striding, near-maximum sprinting, and sprinting. This highlights that previously reported thresholds in Study 1 are likely not quantifying the true sprinting demands. Publicly available injury information indicates a spike in HSI during the 2018 Australian Football League (AFL) season, a trend that occurred in the relatively uninterrupted 2020 AFL season. As Study 2 indicated that thresholds used to quantify the demands of sprinting in training and competition, Study 3 primarily aimed to determine the amount of running completed in relative speed bands during the pre-season and then the first eight weeks of the season. The secondary aim was to determine how individual athletes vary from the group average across the pre-season and the first eight rounds of the season. This study completed a retrospective analysis of 55 professional Australian footballers during the pre-season and first eight rounds of the 2019 season. Significantly less (p < 0.05) weekly volume was reported during the first 8 weeks of the season in the speed thresholds of 71-80%Vmax, 81-90%Vmax, and 91-100%Vmax. However, athletes in this study only completed an average of 18m above 90%Vmax in the pre-season, a stimulus too low to achieve an injury prevention and conditioning effect. Individual analysis highlighted that whilst a small number of athletes achieved a consistent sprinting load, several athletes did not achieve more than 2m above 90%Vmax during both the pre and in-season periods. This lack of preparation may provide a rationale for the injury rates during the first eight rounds. To improve the preparation of athletes using a sprinting stimulus, Study 4 focussed on addressing modifiable risk factors for HSI. The primary aim of this study examined the effects of acceleration and maximum speed sprint training of eccentric hamstring strength, BFLH fascicle length, and sprint performance. Initially, a training study with 60 participants was planned, but due to the Victorian Government’s COVID-19 restrictions, this was modified to a case study design with 11 participants. A 6-week training intervention consisting of acceleration sprinting (<15m) or maximum speed sprinting with a gradual build up (flying 10-20m) was implemented. Participants that performed acceleration or maximum speed sprinting improved Biceps Femoris fascicle length by 23% and 20%, respectively. This was an increase of more than the Minimum Detectable Change (MDC95 = 0.96cm, 95% CI =0.93 – 0.99cm). The participants who completed normal training experienced no change in the BFLH fascicle length. Neither sprint training intervention produced a change in eccentric hamstring strength that was greater than the typical error in the test. Both sprinting interventions improved sprint performance outcomes, however both acceleration and maximum speed training produced a larger improvement in maximum speed (-11% and -9%, respectively) than in acceleration qualities (-2% and -3%, respectively). Both acceleration and maximum speed training incurred positive improvement in relative force production (F(0) (N/kg)) and relative power production (Pmax (W/kg)). This was similar for DRF and RFpeak and indicates that sprint training without resistance will improve Force-Velocity-Power Variables. This project has provided new information regarding the role of sprint training for hamstring strain injury prevention. Firstly, both 6 weeks of low volume acceleration and maximum speed sprinting improve BFLH fascicle length. Secondly, currently employed velocity thresholds in professional AF are likely too slow to quantify the HSR and sprinting demands. Thirdly, analysis using thresholds that are faster than previously reported revealed that the overall volume of sprinting (>90%Vmax) is too low to elicit an injury prevention or training stimulus. This information will inform the future practices of key stakeholders surrounding sprint training in field sport athletes. The identification of the positive benefits of maximum speed sprinting, and a faster, more accurate definition of sprinting has large potential to improve hamstring strain injury prevention and increase physical performance.Doctor of Philosophy
31
Lawlor, Gregory. "An examination of lower limb characteristics during the recovery phase of the sprinting stride in physically awkward children /". Thesis, McGill University, 1992. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=61051.
Testo completoAbstract (sommario):
The purpose of this study was to examine performance characteristics of physically awkward children during the recovery portion of the sprinting stride, and compare them to those of non-awkward children. The dependent variables (length of functional phases, and length and method of power flow at the hip and knee joints) were calculated using the digitized coordinates of selected body landmarks from a high-speed camera film. Statistical analysis was used to interpret the dependent variables, as well as compare them across ability levels.The results revealed no significant differences between ability levels in the dependent variables examined. The findings from this study allow for physically awkward children to be characterized as having abilities for success during the recovery of the sprinting stride. Identifying abilities represents an approach that focusses on a positive view into physical awkwardness, a view which has traditionally been negative. (Abstract shortened by UMI.)
32
Watts, Mark. "Anterior-posterior ground reaction force characteristics for post-block foot contacts in sprint running /". St. Lucia, Qld, 2004. http://adt.library.uq.edu.au/public/adt-QU20041103.152436/index.html.
Testo completo
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Larsson, Claes, e Ljunggren Oscar Wallén. "Skadeförebyggande träningsmetoder mot hamstringsskador inom svensk herrelitfotboll i jämförelse med rekommenderad evidensbaserad forskning". Thesis, Högskolan Dalarna, Idrotts- och hälsovetenskap, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:du-22622.
Testo completoAbstract (sommario):
Purpose The purpose of this study was to describe the evidence-based research recommendations on injury prevention methods against hamstring injuries among Swedish men's elite team in football. The research-based recommendations was then to be compared with the way Swedish elite football teams work to prevent hamstrings injuries. Method First a literature search of PubMed and SPORTDiscuss was made to find the most evidence-based training methods to hamstring injuries. Then an Internet questionnaire regarding injury prevention training methods against hamstring injuries was sent to all Swedish elite football teams. The answers off the questionnaire was then compared with the research that had the most evidence based training methods to hamstring injuries. Results Research shows that the method with the most evidence is eccentric strength training. Flexibility, static stretch and core stability training is research methods that can be used to prevent hamstrings injuries but these methods lack a large validated research basis. 8 of 32 (25 %) teams answered the questionnaire. All teams indicated that they were working with injury prevention methods but the methods varied from the eccentric strength training to periodization and flexibility training. 2 of 8 teams indicated that they worked with eccentric strength training that is recommended by science as the most evidence-based training method. Conclusion The study shows that the teams partly work after what the research recommends as the most evidence-based training methods against hamstring injuries. However, the study lacks validity and further research is needed before definitive conclusions can be drawn.Syfte Syftet med denna studie är att beskriva vilka evidensbaserade forskningsrekommendationer som finns kring skadeförebyggande träningsmetoder mot hamstringsskador hos svenska herrelitlag i fotboll. De forskningsbaserade rekommendationerna ska sedan jämföras med arbetssättet hos herrelitlagen i svensk fotboll. Metod Först gjordes en litteratursökning på databaserna PubMed och SPORTDiscuss för att hitta de mest evidensbaserade träningsmetoderna mot hamstringsskador. Sedan skickades en webbenkät angående skadeförebyggande träningsmetoder mot hamstringsskador ut till alla svenska herrelitfotbollslag. Svaren på enkäten speglades sedan mot vad forskningen rekommenderade som de mest effektiva träningsmetoderna mot hamstringsskador. Resultat Forskning visar att den metoden med mest evidens är excentrisk styrketräning. Rörelse/stretch samt bålstabilitetsträning är enligt forskningen metoder som kan användas för att förebygga hamstringsskador men dessa metoder saknar ett stort validerat forskningsunderlag. 8 av 32 (25%) föreningar besvarade enkäten. Alla föreningar angav att de arbetade med skadeförebyggande åtgärder men metoderna varierade från excentrisk styrketräning till periodisering och rörlighetsträning. 2 av 8 föreningar angav att de arbetade med excentrisk styrketräning som forskningen rekommenderar som den mest evidensbaserade träningsmetoden. Slutsats Studien visar att föreningarna delvis arbetar efter vad forskningen rekommenderar som evidensbaserade träningsmetoder mot hamstringsskador. Dock saknar studien validitet och ytterligare forskning behövs för att slutgiltiga slutsatser ska kunna dras.
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Hancock, Andrew P. "EFFECT OF POST-ACTIVATION POTENTIATION (PAP) ON SWIM SPRINT PERFORMANCE". Cleveland State University / OhioLINK, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=csu1346001907.
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Creekmur, Ceith Clifford-Craig. "Effects of Plyometrics Performed During Warm-up on 20 and 40 Meter Sprint Performance". Miami University / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=miami1305666816.
Testo completo
36
Bushnell, Tyler Dwight. "A biomechanical analysis of sprinters vs. distance runners at equal and maximal speeds /". Diss., CLICK HERE for online access, 2004. http://contentdm.lib.byu.edu/ETD/image/etd634.pdf.
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Thomasian, Ben Campbell. "The effect of vertically- and horizontally-directed plyometric exercise on sprint running performance". Thesis, Edith Cowan University, Research Online, Perth, Western Australia, 2015. https://ro.ecu.edu.au/theses/1598.
Testo completoAbstract (sommario):
The purpose of this investigation was to determine the effect of 6 weeks of vertically- and horizontally-directed lower-body plyometric exercise with vertically versus horizontally biased ground force application, on 40-m sprint running time, vertical jumping height, body composition and gastrocnemius medialis (GM) muscle architecture. Male (n = 19) and female (n = 20) recreational athletes were recruited and stratified according to 40 m sprinting ability, then randomly allocated to one of two groups: horizontally-directed plyometric training (HT) and vertically-directed plyometric training (VT).
The groups performed the experimental procedures twice each week with the same number of total ground contacts, while maintaining their usual weekly training load. During training the subjects performed bounding exercises with maximum effort with either a horizontal or vertical directional bias, depending on the allocated group. Sprinting performance was undertaken on an indoor, sprung-cork running track with the times recorded using infra-red timing gates recording to the nearest 0.01s. Ground reaction forces (GRFs) were recorded using in-ground, multi-component, peizo-electric force platforms.
Changes in performance and muscle function were assessed during counter-movement jumps (CMJs), squat jumps (SJs), and depth jumps (DJs) from 0.20 m (reactive strength index (RSI-20)) and 0.40 m (RSI-40). Muscle fascicle length (FL) and angle pennation (AP) of the GM were assessed using ultrasonography, while dual-energy x-ray absorptiometry (DEXA) was used to determine body fat percentages (BF%) and composition of the shank of the subjects’ dominant legs (push-off leg during sprinting). Multivariate, repeated measures analyses of variance were used to determine differences between training groups and percentage of change scores were calculated for each variable. Both HT and VT presented statistically significant (p ≤ 0.05) with small-to-moderate standardised effect (d) improvements in 10-m (HT: d = 0.22; VT: d = 0.09), 20-m (HT: d = 0.20; VT: d = 0.15), 30-m (HT: d = 0.24; VT: d = 0.23) and 40-m (HT: d = 0.40; VT: d = 0.39) times, with no differences between the groups. No statistical change was seen for either experimental group at 5-m, however a small and trivial practical change was observed for HT (d = 0.20) and VT (d = 0.04) groups. Significant changes were observed for CMJ, SJ, RSI-20 and RSI-40 for both HT and VT groups, without a significant difference between groups. No significant or practical benefit in the change following training was observed for FL (HT: d = 0.02; VT: d = 0.05) or AP (HT: d = 0.04; VT: d = 0.08), with no between group significant differences. Following training significant changes in both experimental groups were observed for BF% (HT: d = 0.13; VT: d = 0.18) and total body mass (HT: d = 0.09; VT: d = 0.09), however there was no significant difference between groups.
The outcomes suggest that HT and VT were similarly effective at improving sprinting and vertical jumping performance, in recreational athletes. The observed outcomes support the use of either movement-specific training paradigms or kinetically dissimilar exercises for the purpose of improving sprinting performance, even though greater forces may be applied.
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Yick, Wing-yan Agnes, e 易詠茵. "The use of analogy to encourage implicit motor learning in children during sprint running". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2003. http://hub.hku.hk/bib/B31257495.
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Koutsoklenis, Isaak-Alexandros. "The efficacy of plyometric training on explosive actions (sprinting, jumping, agility and ball kicking) on the performance of young soccer players". Thesis, Högskolan i Halmstad, Akademin för ekonomi, teknik och naturvetenskap, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:hh:diva-36688.
Testo completoAbstract (sommario):
Background: Plyometric training is a form of conditioning with increasing popularity that involves the performance of body weight jumping type exercises with the use of the stretch-shortening cycle muscle action. It is widely accepted that plyometric training has beneficial effects on many sports, including soccer. Objectives: To assess the effect of plyometric training on explosive actions of soccer performance (sprinting, jumping, agility, ball kicking) and indicated the kind, the frequency and targeted age groups on which the plyometrics should be executed. Methods: A search for all types of trials was performed on Pubmed, Web of Science and Sport Discus databases and the results were recorded according to PRISMA recommendations. 24 studies were included and judged for risk of bias and quality of evidence according to Cochrane guidelines and GRADE. Results: The studies were judges to have “low”, “high” and “unclear” risk of bias and were judged as “moderate”, “low” and very low quality of evidence. The finding of most of the studies show that plyometric training has beneficial effects and statistically significant improvements on the explosive actions (sprinting, jumping, agility and ball kicking) of young soccer players between 10 and 19 years old. Conclusions: The level of evidence of the review is moderate which means that further research is likely to have an important impact on our confidence in the estimate of effect and may change the estimate. The current study suggests that plyometric training can be beneficial for young soccer players when is applied with gradual intensity, frequency of 2-3 times per week and along with regular soccer and strength training. Future research of higher quality of evidence studies and lower risk of bias should be performed in this field.
40
Spencer, Matthew. "Physiological and metabolic responses of repeated-sprint bouts : specific to field-based team sports". University of Western Australia. School of Human Movement and Exercise Science, 2006. http://theses.library.uwa.edu.au/adt-WU2006.0120.
Testo completoAbstract (sommario):
This thesis comprises one review paper and five experimental studies, all of which are presented in the form of journal article submissions. These six research papers attempt to further our understanding of the physiological and metabolic requirements of repeated-sprint activity, specific to field-based team sports. Although coaches and sport scientists have suggested that repeated-sprint ability is an important fitness component of team sports, this area of investigation has only become more common in the past 10 years.
41
Hoffmann, James Jr. "An Investigation of the Sled Push Exercise: Quantification of Work, Kinematics, and Related Physical Characteristics". Digital Commons @ East Tennessee State University, 2014. https://dc.etsu.edu/etd/2422.
Testo completoAbstract (sommario):
The purpose of this dissertation was to describe the basic characteristics of performing resisted sprint training using a push sled for the enhancement of sport performance. Specifically, this dissertation served to: 1.) quantify the frictional forces involved between a push sled and an AstroTurf® surface at 6 loads, 2.) derive an estimation of mechanical work performed during sled push training, 3.) outline the velocity characteristics of 3 sled pushing loads scaled to the athletes body mass for comparison against their sprinting ability and 4.) determine the interrelations of fitness characteristics to the ability to sprint under heavy resistance.
The following are major findings of this dissertation. 1.) Coefficients of static friction (0.53 – 0.37) and dynamic friction (0.35 – 0.28) were calculated at multiple loads for the AstroTurf® surface. 2.) A direct near perfect relationship exists between total system load of the sled and the forces required to initiate and maintain movement of the sled. Although a direct measurement of force would be more precise and account for changes in velocity, the total system load may be a more practical alternative for daily use. 3.) Statistically significant changes in velocity characteristics were observed within each sled pushing load as well as when comparing each load to sprinting. Decrements in peak velocity ranged from about 40%-51% when comparing resisted to unresisted sprinting. Load increments of 25% body mass were heavy enough to cause statistically significant differences in velocity characteristics. 4.) Statistically significant correlations were observed in anthropometry, sprinting ability, jumping ability, and strength to sled pushing. The results indicate that larger athletes, who can not only produce greater force but produce those forces rapidly, in addition to excelling at jumping and sprinting compared to their peers demonstrate the ability to move faster against heavy loads and slow down less from unresisted conditions. The strongest athletes demonstrated statistically nonsignificant differences in peak velocity drop off when compared to their weaker counterparts; however, small to moderate effect sizes (d = 0.27 – 1.02) were observed indicating a practical difference between strength levels in peak velocity and peak velocity drop off.
42
Dimoulas, Peter Michael. "The fast-start and sprinting ability, and the effects of growth hormone (GH) upregulation on the muscle functioning of GH-transgenic coho salmon". Thesis, University of British Columbia, 2009. http://hdl.handle.net/2429/7321.
Testo completoAbstract (sommario):
If GH-transgenic coho salmon escaped into the natural environment would their performance during predator-prey encounters or spawning migrations be different from their wild conspecifics? We examined fast-start and sprinting performance to infer their prospective ability to evade predatory strikes and chasing predators, to chase prey, and to complete spawning migrations. Similarly, we addressed the effects of GH upregulation on muscle functioning. Fast-starts are rapid escape events, and are a summation of short-term behavior, white muscle intrinsic properties, musculoskeletal linking, and body shape. Sprinting additionally reveals the capacity of white muscle to support ATP turnover.
We sought length-matched cohorts, and we examined fast-starts among juveniles, and sprinting among juveniles and adults. We used 3 groups of Coho salmon: GH-transgenic fed to satiation (GHf), wild fed to satiation, and GH-transgenic par-fed according to the fed consumption of wild Coho salmon. For fast-start performance we simulated predatory strikes and quantified the mechanics and escape velocity via high-speed video. For sprinting performance between juveniles we measured: time to exhaustion, anaerobic substrate usage, velocity, and tail-beat frequency. For sprinting between adults, who had similar body lengths (though GHf were significantly longer than wild Coho), we quantified time to exhaustion and velocity.
During fast-starts we found similar mechanics and escape velocity between all groups. We conclude that juvenile GHf may have a similar ability to evade predatory strikes, and GH had no effect on the affectors of fast-starts (we additionally presented across-species comparisons of the effects of GH on muscle enzyme activity, fibre-types, and contractile properties). During sprinting between juveniles, we found similar velocity, tail-beat frequency, and substrate usage; however, GHf took significantly longer to exhaust. We concluded that juvenile GHf might have an enhanced ability to evade chasing predators and to chase prey, due to a higher capacity to support ATP turnover. Between adults, we found similar time to exhaustion, but GHf exhibited significantly lower velocities. While the scaling of velocity offered some insight, differences in body length complicated our analysis. Nevertheless, we suggest that adult GHf may have a reduced ability to evade chasing predators, to chase prey, and to complete spawning migrations.
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Chiang, Chieh-Ying. "Lower Body Strength and Power Characteristics Influencing Change of Direction and Straight-Line Sprinting Performance in Division I Soccer Players: An Exploratory Study". Digital Commons @ East Tennessee State University, 2014. https://dc.etsu.edu/etd/2406.
Testo completoAbstract (sommario):
The purpose of this dissertation was to investigate the influence of lower body strength characteristics on change of direction (COD) performance in NCAA Division I soccer athletes. Specifically, this dissertation served to examine: 1) whether the lower body strength and power were related to COD performance, 2) whether stronger athletes had superior COD performance than weaker athletes, 3) whether the force production asymmetry and strength dominant (SD) associated with COD performance, and 4) weather sex differences existed in kinetic variables during the stand phase of cutting.
The major findings of this dissertation include: 1) strength and power characteristics were moderately to strongly related to COD performance. Furthermore, soccer athletes’ straight-line sprinting times were significantly related to COD performance outcomes. 2) Stronger athletes demonstrated the tendency to perform superiorly in modified 505 COD test when compared to weaker athletes. 3) Athletes who had more lower body force production asymmetry were more likely to perform asymmetrically during a COD test. However, the SD and the magnitude of asymmetry were not limiting factors for athletes’ COD performance.4) Male athletes demonstrated statistically significantly less COD total time, longer ground contact time (GCT), and better ability to apply forces and impulses while performing cutting. Based on the results, vertical forces and impulses during both the braking and propulsive phases of cutting ranged from 2.51 to 3.14 times larger than horizontal direction.
In summary, stronger and more powerful soccer athletes were able to perform in a superior manner for both the COD tasks and straight-line sprinting. This may be due to the ability to produce high force and power during the critical time periods. Although force production asymmetry during related to the asymmetrical performance during COD tasks, the SD and the magnitude of asymmetry did not limit the COD performance. Finally, statistical differences existed between sexes in kinetic variables during cutting may be due to the different approaches to apply force in this task. Moreover, the ability to generate higher force and impulse in the vertical direction could affect COD performance.
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Kruger, Ankebé. "Sport specific talent identification determinants and development of sprinting and long jumping ability among 10-15 year old children from underprivileged communities / Ankebé Kruger". Thesis, North-West University, 2006. http://hdl.handle.net/10394/1318.
Testo completo
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Andrews, Barry. "Sprint analysis of athletes with intellectual impairments". Thesis, Stellenbosch : Stellenbosch University, 2008. http://hdl.handle.net/10019.1/2199.
Testo completoAbstract (sommario):
Thesis (M Sport Sc (Sport Science))--Stellenbosch University, 2008.Intellectually impaired (II) athletes are not allowed to participate at the Paralympic Games because there is no accepted classification system for these athletes. The rationale for this study was to see if there are any physical differences existing in the sprint performance of II and non-II athletes and to see if there is a way to incorporate these differences into a new (accepted) classification system. The objective of this study was to identify any physical sources for the differences between II and non-II, with regard to the acceleration phase, the first 30m of the 60m sprint race, which could then be used in conjunction with other tests in the classification of II athletes. This new classification system might then allow II athletes to participate in the Paralympic Games again. 32 II athletes (22 male and 10 females) and 14 non-II athletes (10 males and 4 females) were used in this study. The sprint performance was analysed and compared of each athlete using the DartFish ProSuite software programme. The data collected from these analysis was then compared using the unpaired t-test, looking for any significant differences between the groups (p<0.05). From this analysis, it was concluded that stride length was the reason for the poorer performance of the II group when compared to the non-II group. Further research is required before definite conclusions can be made on the possible reasons for this difference.
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Pazzagli, Nicola. "Analisi strutturale e biomeccanica di protesi da corsa transtibiali e transfemorali". Bachelor's thesis, Alma Mater Studiorum - Università di Bologna, 2016. http://amslaurea.unibo.it/12312/.
Testo completoAbstract (sommario):
Sono molte le persone che a causa di incidenti, traumi o malattie non riescono a correre e tra le tante lesioni che
non permettono lo svolgimento di questa pratica una in particolare risulta essere piuttosto diffusa, ovvero la mancanza di uno o di entrambi gli arti inferiori.
Ogni amputato deve avere la possibilità di riacquisire l'autonomia che la perdita dell'arto gli ha tolto, ed è proprio per questo che vengono forniti i dispositivi protesici.
Lo scopo di questa tesi è quello di analizzare una protesi sportiva sotto il profilo strutturale e biomeccanico per quanto concerne la corsa. Inizialmente sono descritte le articolazioni che la protesi deve sostituire in base al tipo di amputazione che l'atleta ha subito, nel caso di quella transtibiale la sola caviglia, per quella transfemorale si aggiunge anche il ginocchio. In seguito sono descritti i componenti protesici e i materiali utilizzati nella loro fabbricazione; sono analizzate le procedure di validazione del piede protesico basate sulla normativa ISO 10328. Infine viene spiegata la biomeccanica della corsa e di come la protesi influisce sul pattern motorio dell'atleta durante le varie fasi del movimento; sono analizzate le strategie di compensazione nei soggetti amputati, oltre alle differenze di trasferimento energetico in corsa con gli atleti normali.
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Schultz, Adrian Brent. "The influence of an adapted knee angle, as determined by isokinetic assessment, on sprint starting performance". Thesis, University of Port Elizabeth, 2004. http://hdl.handle.net/10948/317.
Testo completoAbstract (sommario):
Muscle strength has been identified as an important contributor to athletic performance. Little attention however, has been paid to the specific relationship between peak isokinetic muscle strength and sprint starting performance. The aim of this study was to determine the influence of an adapted front knee angle, as determined by isokinetic assessment (the angle of peak torque production), on starting performance. Sixteen track sprinters, of elite-national or competitive-regional standard, were asked to perform eight sprints over 50m using four separate starting techniques. Technique 1 featured the athlete’s usual starting preferences while Techniques 2, 3 and 4 featured a standardised set of starting preferences with experimental modifications of the front knee angle in the “set” position. Isokinetic muscle strength was measured at slow (60°/s) and fast (240°/s) test speeds in order to determine the angle of peak torque production for concentric knee extension of each subject’s lead leg. Using one-way analysis of variance (ANOVA) and Post Hoc analysis (LSD), no significant differences (p>0.05) were observed between the experimental techniques for: block time, force-time measures during block time, sprint times, sprint velocity and acceleratio n measures at intervals up to 50m. Significant differences (p<0.05) were however observed between reaction times for the experimental techniques. Slower reaction times are most likely due to increased upper body pretension, resulting from the increased hip elevation seen for these techniques. The results indicate that increased hip elevation may have delayed the initiation of the relevant motor response required to affect an optimal sprint start. Technique 1 resulted in the shortest reaction times, shortest block times, fastest sprint times and greatest sprint velocities for all four techniques. This result was possibly due to the athlete’s experience with, and repeated use of, this technique. The experimental techniques therefore provided no added advantage over the subject’s preferred starting technique and did not significantly optimise sprint starting performance. The results show that modification of the front knee angle had no significant influence on sprint starting performance and sprint running ve locity or acceleration patterns up to 50m. Using Pearson’s Correlation Coefficient to determine the strongest correlations between isokinetic knee strength and sprint starting performance, analysis revealed that the strongest relationships were found between sprint starting performance expressed as acceleration and isokinetic knee strength expressed as relative peak torque and absolute peak torque. For Technique 1 the strongest correlation was found between acceleration (30m - 40m) and relative peak torque as measured at a test speed of 240°/s (r = 0.62). For the remaining experimental techniques, the strongest correlation was found between acceleration (10m - 20m) and relative peak torque as measured at a test speed of 60°/s (r = 0.53) for Technique 2, between acceleration (40m - 50m) and peak torque measured at a test speed of 60°/s (r = 0.72) for Technique 3, and between acceleration (0m - 5m) and peak torque as measured at a test speed of 240°/s (r = 0.71) for Technique 4. These results suggest that isokinetic muscle strength does not correlate strongly with sprint starting performance and that additional factors, such as neuromuscular organisation and muscle fibre typing, possibly make a greater contribution to optimal sprint starting performance.
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Barr, Matthew John. "A Series of Studies Examining the Development of Sprint Speed and Momentum of International Rugby Union Players". Thesis, Edith Cowan University, Research Online, Perth, Western Australia, 2014. https://ro.ecu.edu.au/theses/1418.
Testo completoAbstract (sommario):
Sprinting speed is a highly valued physical ability in rugby. There is little research examining sprinting biomechanics in rugby players and it is unclear the extent that sprinting speed and sprint momentum can even be improved in highly trained rugby players and how different speed and strength training methods might help improve it. This thesis consists of 6 studies that examine the sprinting biomechanics of elite rugby players, how strength and power training might improve sprinting speed and the potential for elite rugby players to make further improvement in their sprinting speed and sprint momentum.
Key biomechanical factors were that as a player transitions from a standing start to maximal velocity; they do so without an appreciable change in stride rate but with a substantial increase in stride length. Stride rate remains the same because ground contact time and flight time are inversely proportional with each other as they accelerate from a standing start to maximal velocity. Faster players were found to have lower ground contact times and longer stride lengths for both acceleration and maximal velocity. Sprinting with a rugby ball in one hand did not seem to negatively affect international players in either acceleration phases or maximal velocity phases.
Mass was found to have a negative relationship with acceleration and maximal sprinting velocity. Sprint momentum, on the other hand, was found to have a strong positive relationship with body mass. Body mass and height were found to be higher in successful teams at the 2007 and 2011 Rugby World Cups when compared with less successful teams. Senior international players were found to have much greater sprint momentum and body mass, but not sprinting speed, when compared to junior players. Collectively, all of these results point out that sprint momentum is a highly important physical quality. Sprinting speed is an important outcome of training programs but improving sprint momentum by increasing body mass is probably more important. The senior and junior athletes that were tracked for two years were able to effectively improve their sprinting speed and sprint momentum over a two year period which suggests that these are trainable qualities.
Strength and power were found to be important discriminators between fast and slow players. Faster players showed greater results in power clean, front squat, broad jump and triple broad jump. The relationships between these exercises and acceleration were similar for both the slow and fast groups but these exercises had much stronger correlations with maximal sprinting velocity in the slow group then with the fast group. The differences in these relationships seemed to be explained by ground contact time. The group of highly trained players that were tracked over a one year period did not show positive improvement in sprinting speed from increasing the different strength qualities. An 8 day hypergravity condition for international players was ineffective in producing profound changes in sprinting speed. These results suggest that sprinting speed is a trainable quality but there is a limited capacity for strength training to improve it once these qualities have been reasonably well developed in an elite population.
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Elliott, Andrea. "Impact of batting skill on pacing during repeated sprints between the wickets". Thesis, Rhodes University, 2014. http://hdl.handle.net/10962/d1013546.
Testo completoAbstract (sommario):
Introduction: With batting in cricket, there is no known end point, making the allocation of resources and the development of a suitable pacing strategy more difficult. How batsmen allocate resources and pace themselves when repeatedly sprinting between the wickets is therefore not known. According to the ‘anticipatory feedback’ model, the level of expertise/experience has a substantial influence on the development of a suitable pacing strategy. Skilled or experienced batsmen may therefore have a greater ability to develop and implement a pacing strategy compared to that of novice or less-skilled batsmen. Purpose: To assess whether the absence of a known end point at the beginning of repeated sprint bouts between the wickets effects how batsmen pace themselves comparing skilled and less-skilled batsmen. Methods: Twenty-four male cricketers from a university league were selected. Twelve skilled batsmen (players in the top five batting order), and 12 less-skilled batsmen (players in the bottom five batting order) completed three experimental. All trials required batsmen to complete the same number of shuttle sprints (14 shuttles and therefore 28 runs), while only the information provided before each trial differed. Control Trial: This trial is also referred to as the ‘informed’ trial as the batsmen are aware of the exercise requirements (end point). Unknown Trial: The batsmen were not informed of the exercise end point and were required to run on command for an indefinite period (28 runs). Deceptive Trial: Batsmen’ were incorrectly informed with regards to the number of sprints (told they were only doing 14 runs when in fact they were doing 28 runs). Muscle activity, sprint times and RPE measures were obtained during all three trials and compared. Results: Significant (p<0.05) group effects were apparent for sprint times and, ‘central’ and ‘local’ RPE. Specifically, skilled batsmen obtained the faster mean sprint times, and less-skilled batsmen reported the higher mean ‘central’ and ‘local’ RPE values in all three experimental trials. There were no significant group effects for muscle activation. Skilled batsmen did however have lower muscle activation compared to less-skilled batsmen in all three trials. Furthermore, general trends revealed that sprint times and muscle activation decreased over time (from shuttle 1 to shuttle 14), and RPE (‘central’ and ‘local’) ratings increased, regardless of the experimental trials. Skilled batsmen performed the best in all three trials. This was determined by the attainment of faster sprint times, lower muscle activation and low RPE ratings in each of the three trials. The assessment of the relationship of the dependent variables measured in each trial, did however suggest that skilled batsmen performed best in the deceptive trial while less-skilled batsmen performed best in the control trial. Skilled batsmen thus showed superior performance when trial requirements were unclear. Less-skilled batsmen however, were seen to experience decrements in performance when information regarding the end point was unknown or misleading. Conclusion: It can thus be concluded that previous experience facilitates in the obtainment of improved sprint times between the wickets, especially when the exact end point is unknown.
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Mendez, Villanueva Alberto. "Mechanical power output and neuromuscular activity during and following recovery from repeated-sprint exercise in man". University of Western Australia. School of Human Movement and Exercise Science, 2005. http://theses.library.uwa.edu.au/adt-WU2005.0055.
Testo completoAbstract (sommario):
The purpose of the present study was to examine the time-course of mechanical power output and neuromuscular activity during fatiguing repeated-sprint exercise and recovery in man. Prior to the main study, we also investigated the reproducibility of power output during a single 6-s cycling sprint. For this study, eleven healthy moderately trained males performed a 6-s standing sprint on the front-access cycle ergometer on four separate occasions. The results of the study showed that reliable power outputs can be obtained after one familiarization session in subjects unfamiliar with maximal cycling sprint exercise. However, the inclusion of an extra familiarization session ensured more stable power outputs. Therefore, two trials should allow adequate familiarization with the maximal 6-s cycling test. For the main study, eight young moderately trained adult men performed an exercise protocol that consisted of ten, 6-s sprints on a wind-braked cycle ergometer interspersed with 30 s of recovery. After 6 min of passive recovery, five, 6-s sprints were repeated, again interspersed by 30 s of recovery. Peak power output (PPO) and mean power output (MPO) were measured during each sprint and EMG data (i.e., RMS) from the vastus lateralis muscle were also recorded. A one-way ANOVA with repeated measures (i.e., sprint number) was used to allocate the significant differences in each dependent variable over time. Analysis revealed a decline in power output during the fatiguing exercise that was accompanied by a decrease in EMG amplitude of the vastus lateralis muscle. Six minutes after the fatiguing exercise, power output during sprint 11 significantly recovered with respect to values recorded in sprint 10, but remained significantly lower than that recorded in the initial sprint. Thus, 6 min was insufficient to fully recover from the fatiguing repeated sprint protocol utilised in this study. The main findings in the present study were that: 1) the partial recovery of power output in sprint 11 was not accompanied by the recovery V of EMG amplitude; 2) similar mean power outputs were recorded during sprint 4 and 11 despite a significantly lower EMG activity recorded during the latter sprint; and 3) despite comparable mean power outputs during sprint 4 and 11, the decrease in power output over the next five sprints was greater for sprints 11 to 15 than for sprints 4 to 8.