Biomechanics and energetics of running on uneven terrain
Biomechanics and energetics of running on uneven terrain
复制标题
DOI：
10.1242/jeb.106518
复制
发表时间：
2015-03
期刊：
影响因子：
--
通讯作者：
Alexandra S. Voloshina;Daniel P. Ferris
中科院分区：
文献类型：
--
作者：
Alexandra S. Voloshina;Daniel P. Ferris
摘要 在自然界中，有腿动物经常轻松地穿越不平坦的地形。为了了解在不平坦的地形上跑步如何影响运动的生物力学和能量学，我们研究了在不平坦的地形跑步机上以 2.3 m s−1 的速度跑步的人类受试者 (N=12)，高度变化高达 2.5 cm。我们假设，与在平坦的地形上跑步相比，在不平坦的地形上跑步会表现出更高的能量消耗、步数参数变化和腿部刚度。与平坦地形相比，在不平坦地形上跑步时受试者能量消耗增加了 5%（0.68 W kg−1；P<0.05）。步宽和长度变异性也分别增加了 27% 和 26% (P<0.05)。在不平坦的地形上，正负踝关节功分别下降 22% (0.413 J kg−1) 和 18% (0.147 J kg−1)（P=0.0001 和 P=0.0008）。大腿三块肌肉在不平坦地形上的平均肌肉活动增加（P<0.05）。与平坦地形相比，在不平坦地形上跑步时腿部刚度也增加了 20%（P<0.05）。重力势能波动的计算表明，大约一半的能量增加可以通过不平坦表面上的上下台阶的额外正和负机械功来解释。这在步行和跑步之间是一致的，因为在不平坦的地形上步行和跑步的能量消耗的绝对增加相似：分别为 0.68 和 0.48 W kg−1。这些结果让我们深入了解表面光滑度如何影响现实世界中的运动生物力学和能量学。摘要：在不平坦的地形上跑步会导致脚踝正功减少并增加代谢能量消耗。
ABSTRACT In the natural world, legged animals regularly run across uneven terrain with remarkable ease. To gain understanding of how running on uneven terrain affects the biomechanics and energetics of locomotion, we studied human subjects (N=12) running at 2.3 m s−1 on an uneven terrain treadmill, with up to a 2.5 cm height variation. We hypothesized that running on uneven terrain would show increased energy expenditure, step parameter variability and leg stiffness compared with running on smooth terrain. Subject energy expenditure increased by 5% (0.68 W kg−1; P<0.05) when running on uneven terrain compared with smooth terrain. Step width and length variability also increased by 27% and 26%, respectively (P<0.05). Positive and negative ankle work decreased on uneven terrain by 22% (0.413 J kg−1) and 18% (0.147 J kg−1), respectively (P=0.0001 and P=0.0008). Mean muscle activity increased on uneven terrain for three muscles in the thigh (P<0.05). Leg stiffness also increased by 20% (P<0.05) during running on uneven terrain compared with smooth terrain. Calculations of gravitational potential energy fluctuations suggest that about half of the energetic increases can be explained by additional positive and negative mechanical work for up and down steps on the uneven surface. This is consistent between walking and running, as the absolute increases in energetic cost for walking and running on uneven terrain were similar: 0.68 and 0.48 W kg−1, respectively. These results provide insight into how surface smoothness can affect locomotion biomechanics and energetics in the real world. Summary: Running on uneven terrain leads to decreased positive ankle work and increased metabolic energy expenditure.