Non-extension movements inducing over half the mechanical energy directly contributing to jumping height in human running single-leg jump

[摘要] The running single-leg jump (RSLJ), including certain non-extension movements (movements not induced by lower-limb extension works), is the highest jumping mode in humans. Here, we show the substantial contributions of non-extension movements, in generating mechanical energy directly contributing to the jumping height (E-vert) in RSLJ. We determined the component of increase in E-vert due to each segment movement in RSLJs by 13 male high-jumpers. The stance-leg shank forward rotation (rotation opposite to the actions of the knee extensors and ankle plantar flexors on the shank), increased E-vert (0.76 +/- 0.70 J/kg). E-vert due to the stance-leg thigh forward rotation (4.39 +/- 0.57 J/kg) was substantially larger than the inflowing energy into the thigh (difference: 2.36 +/- 0.42 J/kg). These results suggest that the forward rotations of the shank and thigh transformed horizontal kinetic energy (E-hori) to E-vert.E-vert was increased by the elevation of the free-leg side of the pelvis (0.53 +/- 0.22 J/kg) and rotation of free-leg thigh (1.52 +/- 0.26 J/kg). The non-extension movements contributed to over half (59 +/- 6%) the increase in E-vert during the take-off phase. Human-specific morphologies are essential for the contributions of non-extension movements; fully extensible knee joints and relatively longer legs with respect to body mass for the transformation from E-hori to E-vert by shank and thigh rotations, and a wide and short pelvis for increasing E-vert by pelvic elevation. This study provides quantifiable evidence to indicate how substantially non-extension movements contribute to higher RSLJ. (C) 2020 The Authors. Published by Elsevier Ltd.

[发布日期] 2020-12-02

[关键词] Three-dimension;External work;Human-specific;Pivoting movement