Natural Science Division, Pepperdine University, Malibu, CA 90263, USA.
Percept Mot Skills. 2011 Feb;112(1):228-42. doi: 10.2466/05.10.25.PMS.112.1.228-242.
Time course of changes in jump height was examined to assess whether it was related to changes in the underlying mechanics or muscle activity. In Phase I, 11 novice female students performed 10 maximal jumps for eight consecutive days from two force plates. Jump height, impulse duration (t(IMP)), and mean vertical ground reaction force (VGRF) were compared using repeated-measures analysis of variance. Jump height was significantly higher (7.7%) on Days 3-8 when compared to Days 1 and 2; t(IMP) and VGRF were unchanged across days. In a followup study (Phase II), 14 novice female students performed 10 maximal jumps for five consecutive days. Electromyographic activity of five leg muscles was recorded to identify the relative onset of each muscle's activity. Using repeated-measures analysis of variance, jump height was significantly higher (4.2%) on Days 2 to 5 compared to Day 1; however, no significant changes were found across Days, for t(IMP), VGRF, or the onset of muscle activity. The findings indicate that jump performance can improve rapidly in novice jumpers but the underlying muscle activation remained unchanged.
时间进程中跳跃高度的变化被检测，以评估其是否与潜在力学或肌肉活动的变化有关。在第一阶段，11 名女性新手学生从两个测力板上连续 8 天进行了 10 次最大跳跃。使用重复测量方差分析比较了跳跃高度、冲量持续时间（t(IMP)）和平均垂直地面反作用力（VGRF）。与第 1 天和第 2 天相比，第 3 天至第 8 天的跳跃高度显著提高（7.7%）；t(IMP)和 VGRF 在整个测试期间没有变化。在后续研究（第二阶段）中，14 名女性新手学生连续 5 天进行了 10 次最大跳跃。记录了 5 条腿部肌肉的肌电图活动，以确定每条肌肉活动的相对起始时间。使用重复测量方差分析，与第 1 天相比，第 2 天至第 5 天的跳跃高度显著提高（4.2%）；然而，在整个测试期间，t(IMP)、VGRF 或肌肉活动的起始时间都没有发现显著变化。研究结果表明，新手跳跃者的跳跃表现可以迅速提高，但潜在的肌肉激活保持不变。
