Understanding biomechanical differences in technique between phases of a sprint
von Lieres und Wilkau, Hans Christian
Cardiff Metropolitan University
MetadataDangos cofnod eitem llawn
Sprinting requires the rapid development of velocity while technique changes across multiple steps. Research Themes (Phase analysis, Technique analysis and Induced acceleration analysis) were formulated to investigate and understand the biomechanical differences in technique between the initial acceleration, transition and maximal velocity phases of a sprint. Theme 1 (Phase analysis) revealed relatively large changes in touchdown variables (e.g. centre of mass height, touchdown distances, shank angles) during the initial acceleration phase. This likely reflects an increasing need to generate larger vertical forces early during stance as a sprint progresses. At toe-off, smaller yet progressive changes in variables (e.g. trunk angles and centre of mass height) across the initial acceleration and transition phases reflect a constraint determining decreases in propulsive forces during a sprint. Theme 2 (Technique analysis) revealed a trend linking smaller horizontal foot velocities and touchdown distances with smaller braking impulses during the transition and maximal velocity phases. Furthermore, moderate to large increases in negative work by the ankle plantar flexors and knee extensors suggests an increased contribution to absorb forces at those joints and maintain the height of the centre of mass as a sprint progresses. Finally, theme 3 (Induced acceleration analysis) revealed that the braking impulses relative to body mass (expressed in m·s-1) due to the accelerations at contact point, which largely resulted from the foot being decelerated at touchdown, increased from -0.01 ± 0.01 m·s-1 to -0.08 ± 0.02 m·s-1 between steps three to 19 of a sprint. The ankle moment provided the largest contributions to centre of mass acceleration throughout stance with the changing orientation of the ground reaction force vector ultimately determined by the increasing foot, shank and trunk angles as the sprint progressed. This thesis developed the conceptual understanding of the technical differences between different phases of sprinting. It will contribute to the development and evaluation of sprinting technical models associated with different phases of the event and provide a greater understanding of key contributors to performance. As a sprint progresses, sprinters should emphasise the development of the leg mechanics during the terminal swing and early stance phases to ensure step-to-step changes in braking impulses are managed.
PhD Thesis- School of Sport and Health Sciences
Yn dangos eitemau sy’n perthyn drwy deitl, awdur, pwnc a chrynodeb.
World-Class Male Sprinters and High Hurdlers Have Similar Start and Initial Acceleration Techniques Bezodis, Ian; Brazil, Adam; von Lieres und Wilkau, Hans Christian; Wood, Matthew; Paradisis, Giorgios; Hanley, Brian; Tucker, Catherine; Pollitt, Lysander; Merlino, Stéphane; Vazel, Pierre-Jean; Walker, Josh; Bissas, Athanassios (Frontiers Media, 2019-08-27)The effect of the inclusion of a high hurdle 13.72 m after the start line on elite sprint start and initial acceleration technique has yet to be investigated or understood. This highly novel study addresses that lack of ...
"How do the lower extremity biomechanics of a sprint track athlete differ from an endurance athlete during the stance phase at high velocity running?" peterson, Jessica (University of Wales Institute Cardiff, 2012)The aim of the study was to examine the lower extremity biomechanics of the stance phase of sprint and endurance athletes, performing maximum velocity sprint runs. The overall purpose of the study was to assist the development ...
Comparing lower leg kinematics and coordination in sprint acceleration with and without the constraint of holding a field hockey stick Wdowski, Maximilian (University of Wales, 2011-10-25)The importance of rapid sprint acceleration in team based sport performance has been well established. Sports scientists have created a number of training techniques, such as interval sprint training, to improve the ...