ABSTRACT
In high jump, the thigh and shank rotations mainly induce the effective energy for height () by directly or indirectly (via joint work) converting horizontal-kinetic energy. Meanwhile, inter-individual differences in
may not only be explained by large contributors. Here we show that the
components due to relatively small contributor segments share variance with total
while those due to the two largest contributor segments do not, by analyzing high jump of 15 male jumpers (personal best: 1.90–2.31 m). The largest
components were from the stance-leg thigh and shank (36 ± 7%, 34 ± 7% of total
), but each of them did not significantly share variance with total
(r2 < 0.12). Meanwhile, each of the thoracic and stance-leg-foot components significantly shared variance with total increase in
(r2 > 0.30), despite their relatively small contributions (11 ± 2%, 4 ± 1%). The stance-leg thigh and shank components had a strongly trade-off relationship (r2 = 0.60). We reveal that large contributors to the performance variable do not directly imply by their large contribution that they explain inter-individual differences in motor performance, and vice versa. We provide an example where large contributors to the performance variable are related to individually different strategies for achieving performance rather than to performance itself.
Disclosure statement
No potential conflict of interest was reported by the author(s).
Ethics approval statement
The Human Research Ethics Committee at the University of Tsukuba, Japan, approved the study protocol (A reference number: PE021–140).