Nebraska Biomechanics Core Facility, School of Health, Physical Education and Recreation, College of Education, University of Nebraska at Omaha, Omaha, NE 68182, USA.
Gait Posture. 2012 Feb;35(2):203-8. doi: 10.1016/j.gaitpost.2011.09.007. Epub 2011 Oct 1.
Previous research on the biomechanics of stair negotiation has ignored the effect of the approaching speed. We examined if initiating stair ascent with a comfortable self-selected speed can affect the lower-extremity joint moments and powers as compared to initiating stair ascent directly in front of the stairs. Healthy young adults ascended a custom-built staircase instrumented with force platforms. Kinematics and kinetics data were collected simultaneously for two conditions: starting from farther away and starting in front of the stairs and analyzed at the first and second ipsilateral steps. Results showed that for the first step, participants produced greater peak knee extensor moment, peak hip extensor and flexor moments and peak hip positive power while starting from farther away. Also, for both the conditions combined, participants generated lesser peak ankle plantiflexor, greater peak knee flexor moment, lesser peak ankle negative power and greater peak hip negative power while encountering the first step. These results identify the importance of the starting position in experiments dealing with biomechanics of stair negotiation. Further, these findings have important implications for studying stair ascent characteristics of other populations such as older adults.
先前关于楼梯上下运动的生物力学研究忽略了接近速度的影响。我们研究了与直接在楼梯前开始相比，以舒适的自选择速度开始上楼梯是否会影响下肢关节的力矩和功率。健康的年轻成年人登上了一个带有测力平台的定制楼梯仪器。同时收集了两种情况下的运动学和动力学数据：从更远的地方开始和从楼梯前开始，并在第一和第二同侧台阶上进行分析。结果表明，对于第一步，参与者从更远的地方开始时，产生了更大的膝关节伸展峰值力矩、髋关节伸展和屈曲峰值力矩以及髋关节正功率峰值。此外，对于两种情况的综合分析，参与者在遇到第一级台阶时，产生了较小的踝关节跖屈峰值力矩、较大的膝关节屈曲峰值力矩、较小的踝关节负功率峰值和较大的髋关节负功率峰值。这些结果确定了在涉及楼梯上下运动生物力学的实验中起始位置的重要性。此外，这些发现对于研究其他人群（如老年人）的楼梯上升特征具有重要意义。
