Smith John D, Guerra Gary
Department of Counseling, Health and Kinesiology, Texas A&M University-San Antonio, San Antonio, TX, USA.
Department of Exercise and Sport Science, St. Mary's University, San Antonio, 1 Camino Santa Maria, San Antonio, TX, 78228, USA.
Sci Rep. 2025 Sep 25;15(1):32914. doi: 10.1038/s41598-025-18094-8.
The purpose of this study was to evaluate oxygen uptake kinetics and biomechanics during two and six minute walk tests in individuals with lower limb prosthesis (iLLA) and unimpaired persons. Participants performed both 2MWT and 6MWT, oxygen uptake (VO), heart rate (HR) and temporal-spatial parameters were recorded. Repeated measures factorial ANOVAs analyzed differences between tests and groups, Alpha was set at 0.05. There were no significant differences in VO or HR between iLLA and unimpaired groups at any time point during either walk (p > 0.05), and neither group achieved steady state during the 2MWT, whereas steady-state HR appeared after minute 4 of the 6MWT in both groups. iLLA walked significantly less distance (p < 0.05) but had similar cadence and total steps during each test compared with unimpaired (p > 0.05). iLLA also had significantly greater stance ratios and shorter stride length compared with the unimpaired group (p < 0.05) and stride length was also shorter in iLLA during the 6MWT compared to the 2MWT (p < 0.05). The 2MWT is a strong predictor of 6MWT in the unimpaired group (r = 0.76, p = 0.001) and stronger in those using prostheses (r = 0.94, p = 0.001). Although 2MWT was a strong predictor of 6MWT performance in both groups, marked physiological and biomechanical differences were observed. Our findings do not support use of 2MWT as a proxy for 6MWT in lower limb prosthesis users.
本研究旨在评估下肢假肢使用者（iLLA）和未受损个体在2分钟和6分钟步行测试期间的摄氧动力学和生物力学。参与者进行了2MWT和6MWT测试，记录了摄氧量（VO）、心率（HR）和时空参数。重复测量析因方差分析用于分析测试和组间差异，α设定为0.05。在任何一个步行阶段的任何时间点，iLLA组和未受损组之间的VO或HR均无显著差异（p>0.05），并且两组在2MWT期间均未达到稳态，而两组在6MWT的第4分钟后均出现稳态心率。与未受损个体相比，iLLA在每次测试中行走的距离明显较短（p<0.05），但步频和总步数相似（p>0.05）。与未受损组相比，iLLA的站立比例也显著更高，步幅更短（p<0.05），并且在6MWT期间iLLA的步幅也比2MWT期间更短（p<0.05）。在未受损组中，2MWT是6MWT的有力预测指标（r=0.76，p=0.001），在使用假肢的个体中预测性更强（r=0.94，p=0.001）。尽管2MWT在两组中都是6MWT表现的有力预测指标，但观察到明显的生理和生物力学差异。我们的研究结果不支持将2MWT作为下肢假肢使用者6MWT的替代指标。
