在重复使用负载计移动跳跃的功率能力评估期间,力-时间曲线的变化
Alex O Natera1,2, Steven Hughes1, Dale W Chapman3
1Sport Science, New South Wales Institute of Sport, Sydney Olympic Park, New South Wales, Australia.
PeerJ
|October 8, 2024
概括
力量-时间曲线的统计参数映射 (SPM) 显示了重复功率能力 (RPA) 评估中的性能下降. 较低的RPA得分与制动和推进阶段的更大力产生有关.
科学领域:
- 运动科学 运动科学 运动科学
- 生物力学 生物力学
- 人类运动分析 人类运动分析
背景情况:
- 传统的重复功率能力 (RPA) 评估依赖于离散变量,如峰值功率输出.
- 分析整个力-时间曲线可以更深入地了解RPA性能变化.
研究的目的:
- 使用统计参数映射 (SPM) 在RPA评估期间分析力-时间曲线的变化.
- 为了比较具有低和高RPA分数的参与者之间的力-时间曲线差异.
主要方法:
- 11名田间曲棍球运动员进行了20次负载反运动跳跃 (LCMJ20).
- 使用SPM分析了力时数据,计算了峰值功率和RPA百分比下降 (RPA%dec).
- SPM单向ANOVA和独立的t测试发现了显著的变化和群体差异 (α=0.05,p<0.001).
主要成果:
- 随着LCMJ20的进步,推进力从运动的74-98%显著下降 (p<0.001).
- 在跳跃系列1和2 (70-98%) 和系列1和3 (86-99%) 之间,力量差异最大.
- 具有较低RPA%dec分数的参与者表现出更大的制动和推进力 (p<0.001).
结论:
- 在LCMJ20期间,晚期推进阶段的力量减少显而易见.
- 在RPA评估过程中,SPM分析提升了对力-时间曲线变化的理解.
- 较低的RPA%dec分数表明高峰功率的优越维护,反映在更大的制动和推进力中.
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