Academic literature on the topic 'Bounding exercises'

AbstractPlyometric exercises such as drop jumping and bounding offer athletes a substantiated means of enhancing athletic performance. Between the two exercises, reactive measurement using bounding (reactive bounding coefficient [RBC]) has received scant attention within the domain of training and conditioning. Therefore, this study aimed to identify the viability of utilising a speed-bounding exercise to assess horizontal reactive strength. Eleven young, male elite sprinters (age: 17.8 ± 1.3 yr; body height: 1.72 ± 0.06 m; body mass: 66.05 ± 6.10 kg; best 100 m sprint time: 10.77 ± 0.32 s) were tested for static jumps (SJ), drop jumps (DJ), 10 speed-bounding (RBC10), and 50 m sprint performance. Between-group comparisons based on sprint ability (fast [FSG] vs. slow [SSG] sprint-group) and correlation coefficients were computed subsequently. The FSG (n = 5; 50 m time: 5.82 ± 0.11 s; RBC10: 7.46 ± 0.27) performed significantly better in the RBC10 (p = 0.036) than the SSG (n = 5; 50 m time: 6.09 ± 0.13 s; RBC10: 7.09 ± 0.25). A very high correlation was attained between the RBC10 and the criterion measure, the SJ (r = 0.83). Additionally, RBC10 appeared to be correlated with 30, 50, 10-30 and 30-50 m sprint times (r = -0.52 to -0.60). This positive trend, however, was not observed for the DJ reactive strength index (trivial to moderate correlations). Good reliability was shown for the RBC10 and all sprint distances (“1.5% coefficient variation). Furthermore, all sprinters attained ground contact times of 0.12-0.18 s during the RBC10 which was indicative of fast stretch-shortening cycles during movement, suggesting that the RBC10 could be utilised to assess plyometric ability and enhance sprint performance. Overall, the RBC10 seems able to discriminate between the FSG and the SSG, indicating it has acceptable levels of validity and reliability.

AbstractJump distance per step in bounding exercises from the standing position increases with increasing number of steps. We examined the hypothesis that the joint kinetic variables of the stance leg would also increase accordingly. Eleven male athletes (sprinters and jumpers) performed bounding exercise, starting from the double-leg standing posture, and covered the longest distance possible by performing a series of seven forward alternating single-leg jumps. Kinematic and kinetic data were calculated using the data by a motion capture system and force platforms. Hip extension joint work were decreased at third step (1st: 1.07±0.22, 3rd: 0.45±0.15, 5th: 0.47±0.14 J•kg−1; partial η2: 0.86), and hip abduction joint power were increased (1st: 7.53±3.29, 3rd: 13.50±4.44, 5th: 21.37±9.93 W•kg−1; partial η2: 0.58); the knee extension joint power were increased until the third step (1st: 14.43±4.94, 3rd: 17.13±3.59, 5th: 14.28±2.86 W•kg−1; partial η2: 0.29), and ankle plantar flexion joint power increased (1st: 34.14±5.33, 3rd: 37.46±4.45, 5th: 40.11±5.66 W•kg−1; partial η2: 0.53). These results contrast with our hypothesis, and indicate that increasing the jump distance during bounding exercises is not necessarily accompanied by increases in joint kinetics of stance leg. Moreover, changes in joint kinetics vary at different joints and anatomical axes.

The objectives of this study are to study and test the effect of using the effect of the single leg and double leg bounding exercise program (BEP) on the improvement of physical agility, strength, balance, and leg muscle power. The subjects of this study were 42 students of Physical Education class 2017 STKIP PGRI Jombang.This type of research is quantitative with quasi-experimental techniques. Sampling using the Solvin formula and purposive sampling technique. The process of taking data from the initial test and the final test uses the leg dynamometer test to determine leg muscle strength, side step test for agility, force plate test for leg muscle power, and balance beam test for balance.The results of the study on the normality and homogeneous tests showed normal and homogeneous data results with a significance value above 0.05. The mean difference test was carried out using the paired test and the Manova test. The method of increasing the agility, strength, balance and leg muscle power has a significant improvement with the two experimental methods.The conclusion of this study is that the bounding exercise program can significantly increase the agility, strength, balance and leg muscle power. However, from the two exercises the increase was greater in the group using the single leg bounding type of exercise.

This study was undertaken to compare force-time characteristics, muscle power, and electromyographic (EMG) activities of the leg muscles in maximal sprinting and in selected bounding and jumping exercises. Seven male sprinters performed maximal bounding (MB), maximal stepping (MS), maximal hopping with the right (MHR) and left (MHL) legs, and maximal sprint running (MR). These “horizontal” exercises and running were performed on a force platform. EMG activity was telemetered unilaterally from five leg muscles during each trial. The results indicated significant (p < .001) differences among the studied exercises in velocity, stride length, stride rate, flight time, and contact time. Also, significant differences were noticed in reactive forces (p < .01-.001) and power (p < .01) among the performances, whereas only insignificant differences were observed in EMG patterns. The average resultant forces during the braking and propulsion phases in MS, MHR, and MHL were greater (p < .001) than in MR and MB. Stepping and hopping are cyclic and sprint-specific and may be used as strength exercises for sprinters because of great strength demand.

Millions of high school students take Advanced Placement (AP) courses, which can provide college credit. Using nationally representative data, I identify a diverse set of higher education outcomes that are related to receipt of AP college credit. Institution fixed effects regression reduces bias associated with varying AP credit policies and student sorting across higher education. Results indicate college credits earned in high school are related to reduced time to degree, double majoring, and more advanced coursework. Bounding exercises suggest the time to degree and double major outcomes are not likely driven by bias from unobserved student characteristics. Policies used to support earning college credits while in high school appear to enhance undergraduate education and may accelerate time to degree.

This paper presents an action recognition approach based on shape and action descriptors that is aimed at the classification of physical exercises under partial occlusion. Regular physical activity in adults can be seen as a form of non-communicable diseases prevention, and may be aided by digital solutions that encourages individuals to increase their activity level. The application scenario includes workouts in front of the camera, where either the lower or upper part of the camera’s field of view is occluded. The proposed approach uses various features extracted from sequences of binary silhouettes, namely centroid trajectory, shape descriptors based on the Minimum Bounding Rectangle, action representation based on the Fourier transform and leave-one-out cross-validation for classification. Several experiments combining various parameters and shape features are performed. Despite the presence of occlusion, it was possible to obtain about 90% accuracy for several action classes, with the use of elongation values observed over time and centroid trajectory.

The wheel-legged hybrid robot (WLHR) is capable of adapting height and wheelbase configuration to traverse obstacles or rolling in confined space. Compared with legged and wheeled machines, it can be applied for more challenging mobile robotic exercises using the enhanced environment adapting performance. To make full use of the deformability and traversability of WHLR with parallel Stewart mechanism, this paper presents an optimization-driven planning framework for WHLR with parallel Stewart mechanism by abstracting the robot as a deformable bounding box. It will improve the obstacle negotiation ability of the high degree-of-freedoms robot, resulting in a shorter path through adjusting wheelbase of support polygon or trunk height instead of using a fixed configuration for wheeled robots. In the planning framework, we firstly proposed a pre-calculated signed distance field (SDF) mapping method based on point cloud data collected from a lidar sensor and a KD -tree-based point cloud fusion approach. Then, a covariant gradient optimization method is presented, which generates smooth, deformable-configuration, as well as collision-free trajectories in confined narrow spaces. Finally, with the user-defined driving velocity and position as motion inputs, obstacle-avoidancing actions including expanding or shrinking foothold polygon and lifting trunk were effectively testified in realistic conditions, demonstrating the practicability of our methodology. We analyzed the success rate of proposed framework in four different terrain scenarios through deforming configuration rather than bypassing obstacles.

The equations for fluid substitution in a sample with known porosity and the mineral’s and pore-fluid’s elastic moduli are well-documented. Discussions continue on how to conduct fluid substitution in practical situations where more than one fluid phase is present and the porosity and mineralogy are not precisely defined. We pose a different question: If we agree on a fluid substitution method, and also agree that at partial saturation the bulk modulus of the “effective” pore fluid is the harmonic average of those of the components, can we conduct fluid substitution directly on the seismic reflection amplitude? To address this question, we conducted forward modeling synthetic exercises: We systematically varied the porosity, clay content, and thickness of the reservoir and assumed that the properties of the bounding shale are fixed. Next, we used a velocity-porosity model to compute the elastic properties of the dry-rock frame and applied Gassmann’s equation to compute these properties in wet rock as well as at partial gas saturation. After that, we generated prestack synthetic seismic reflections at the top of the reservoir at full saturation and at partial saturation, and related one to the other. We found that within our assumption framework, there is an almost linear relation between the intercepts of the P-to-P reflectivity for the wet and gas reservoir. The same is true for the gradients. We have provided best-linear-fit equations that summarize these results. We applied this technique to field data and found that we can approximately predict the seismic amplitude at a gas reservoir from that measured at a wet reservoir, given that all other properties of the rock remain fixed. The solution given here should be treated as a method, meaning it should be tested and modified for various rock types and textures.

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.

This thesis proposes a novel approach to extracting pose information from image sequences. Current state of the art techniques focus exclusively on the image space occupied by the body for pose and action recognition. The method proposed here, however, focuses on the negative spaces: the areas surrounding the individual. This has resulted in the colour-coded negative space approach, an image preprocessing step that circumvents the need for complicated model fitting or template matching methods. The approach can be described as follows: negative spaces surrounding the human silhouette are extracted using horizontal and vertical scanning processes. These negative space areas are more numerous, and undergo more radical changes in shape than the single area occupied by the figure of the person performing an action. The colour-coded negative space representation is formed using the four binary images produced by the scanning processes. Features are then extracted from the colour-coded images. These are based on the percentage of area occupied by distinct coloured regions as well as the bounding box proportions. Pose clusters are identified using feedback from an independent action set. Subsequent images are classified using a simple Euclidean distance measure. An image sequence is thus temporally segmented into its corresponding pose representations. Action recognition simply becomes the detection of a temporally ordered sequence of poses that characterises the action. The method is purely vision-based, utilising monocular images with no need for body markers or special clothing. Two datasets were constructed using several actors performing different poses and actions. Some of these actions included actors waving their arms, sitting down or kicking a leg. These actions were recorded against a monochrome background to simplify the segmentation of the actors from the background. The actions were then recorded on DV cam and digitised into a data base. The silhouette images from these actions were isolated and placed in a frame or bounding box. The next step was to highlight the negative spaces using a directional scanning method. This scanning method colour-codes the negative spaces of each action. What became immediately apparent is that very distinctive colour patterns formed for different actions. To emphasise the action, different colours were allocated to negative spaces surrounding the image. For example, the space between the legs of an actor standing in a T - pose with legs apart would be allocated yellow, while the space below the arms were allocated different shades of green. The space surrounding the head would be different shades of purple. During an action when the actor moves one leg up in a kicking fashion, the yellow colour would increase. Inversely, when the actor closes his legs and puts them together, the yellow colour filling the negative space would decrease substantially. What also became apparent is that these coloured negative spaces are interdependent and that they influence each other during the course of an action. For example, when an actor lifts one of his legs, increasing the yellow-coded negative space, the green space between that leg and the arm decreases. This interrelationship between colours hold true for all poses and actions as presented in this thesis. In terms of pose recognition, it is significant that these colour coded negative spaces and the way the change during an action or a movement are substantial and instantly recognisable. Compare for example, looking at someone lifting an arm as opposed to seeing a vast negative space changing shape. In a controlled research environment, several actors were instructed to perform a number of different actions. After colour coding the negative spaces, it became apparent that every action can be recognised by a unique colour coded pattern. The challenge is to ascribe a numerical presentation, a mathematical quotation, to extract the essence of what is so visually apparent. The essence of pose recognition and it's measurability lies in the relationship between the colours in these negative spaces and how they impact on each other during a pose or an action. The simplest way of measuring this relationship is by calculating the percentage of each colour present during an action. These calculated percentages become the basis of pose and action recognition. By plotting these percentages on a graph confirms that the essence of these different actions and poses can in fact been captured and recognised. Despite variations in these traces caused by time differences, personal appearance and mannerisms, what emerged is a clear recognisable pattern that can be married to an action or different parts of an action. 7 Actors might lift their left leg, some slightly higher than others, some slower than others and these variations in terms of colour percentages would be recorded as a trace, but there would be very specific stages during the action where the traces would correspond, making the action recognisable.In conclusion, using negative space as a tool in human pose and tracking recognition presents an exiting research avenue because it is influenced less by variations such as difference in personal appearance and changes in the angle of observation. This approach is also simplistic and does not rely on complicated models and templates

Every Native Nation is a “border nation”— physically, economically, politically, and legally. As such, the volatile topic of these Native Nation boundaries is historically and contemporarily enmeshed with contestation and conflict, not only in the larger political actions of these states but also as it is felt in the daily lives of American Indian peoples. Boundaries of territory and citizenry in particular have always been crucial to the subject of American Indian rights. The delineations of these boundaries, then, have complications and consequences for the exercise of EBCI economic sovereignty as well as for the small- business owners that choose to operate there. These boundary formations are critical to understanding the contextual distinctiveness of federally recognized American Indian entrepreneurs through land rights, formation of citizenship requirements, and issues of representation (especially in relation to citizenship). This chapter looks specifically at the issues of land scarcity, trust land for Native Nations and their citizens, the cultural capital of this land in a tourism context, and the environmental impacts of economic development. Land scarcity may also cause citizens to leave the Qualla Boundary, resulting in some instances in brain drain, networking loss, and economic drain. The importance of citizenship, along with its complications, are illustrated through the efforts of Eastern Band of Cherokee Indians artists and their strategies to market their work.