Introduction The purposes of this research were to design and develop a set of speeds-control jumping equipment that could intensify specific ability of long jumpers' take-off leg, and used it to test the take-off, so as to make a preliminary biomechanics assessment of dynamic adaptability in long jump training. Methods Nine male long jumpers were required to perform take-off in the equipment; the speeds-control in the experiment were 6m.s-1, 7m.s-1, 8m.s-1, and 9m.s-1 respectively. As well as all subjects were required to complete running long jump take-off. All kinematics and dynamics data were gained by high two high-speed video cameras (JVC9800, 100Hz, 200Hz), a force platform (500Hz, Kistler 9281B) and an accelerometer (1000Hz) synchronized measuring and analyzed. The `inverse dynamics` method [1] was used to calculate the muscles moment of hip, knee and ankle of the take-off leg. Results The figure 1 (a, b, c) showed the average results of all subjects` joint moment of hip, knee and ankle in different speeds-control testing (SCT), and figure 2 (a, b, c) were their comparisons between SCT (9m.s-1) and long jump, respectively. Joint moment=Moment/BW (N.m/kg), Time=Normalized time (%). Positive=extend, Negative=flex. Discussion / Conclusions The results of different speed-control testing in the equipment well reflected the muscles' active characteristic of hip, knee and ankle. It was accordance with long jump. In SCT, with the controlling speed increasing (6 m.s-1-9 m.s-1), the muscles contraction ability enhanced. All joints (Hip, Knee and ankle) chiefly presented extensors moment in take-off, especially, in earlier phase of take-off (within 30%). The ability of fast eccentric, concentric contraction and the switch velocity from eccentric to concentric were important to take-off. In running long jump, the larger peak of knee flexion moment emerged in earlier take-off phase (within 8%), which indicated the knee flexion muscles actively contracted in this period. It must draw coaches` and athletes` attention in training.
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