It was suggested that the neural input used in the fatigued condition did not constitute an optimal solution and may have played a role in decreasing maximal jump height achievement.

It was indicated that countermovement jumps were performed with a consistent well-timed motion of the segments. A "common drive," which acts without the knowledge of the muscle properties, was suggested as mediating and controlling the muscle activation timing between agonist-antagonist muscle pairs.

This study was concerned with the measurement of performance variables from competitors in the men's long jump final of the World Student Games held in Sheffield, England, in July 1991. Several performances of 10 finalists were recorded on cine film at 100 Hz. Resulting sagittal plane kinematic data were obtained for the last stride, touchdown, and takeoff for a total of 27 jumps. It was confirmed that takeoff velocity was a function of touchdown velocity, and that there was an increase in vertical velocity at the expense of a reduction of horizontal velocity. It was concluded that there was evidence for mechanisms which may be termed mechanical, biomechanical, and muscular. The former relates to the generation of vertical velocity by the body pivoting over the base of support during the compression phase, and a lifting of the arms and free leg during the lift phase; the second is the elastic reutilization of energy; and the third is the contribution by concentric muscular contraction.