The purpose of this study was to examine the changes in both the coordination patterns of segmental actions and the dynamics of vertical jumping that accompany changes in vertical jump performance (VJP) occurring from trial to trial in single subjects. Ground reaction forces and video data were analyzed for 50 maximal vertical jumps for 8 subjects. It was possible to predict VJP from whole-body or even segmental kinematics and kinetics in spite of the small jump performance variability. Best whole-body models included peak and average mechanical power, propulsion time, and peak negative impulse. Best segmental models included coordination variables and a few joint torques and powers. Contrary to expectations, VJP was lower for trials with a proximal-to-distal sequence of joint reversals.
Luis F. Aragon-Vargas is with the Escuela de Educación Física y Deportes, Universidad de Costa Rica, San José, Costa Rica. M. Melissa Gross is with the Department of Movement Science, The University of Michigan, Ann Arbor, MI 48109. Request reprints from Luis F. Aragón-Vargas, Apdo. 686, 2350 San José, Costa Rica. E-mail: firstname.lastname@example.org