Department of Biomechanics, University of Nebraska at Omaha, 6160 University Dr S., Omaha, NE, 68182, USA.
Department of Kinesiology and Applied Physiology, University of Delaware, Newark, DE, USA.
Biomed Eng Online. 2021 Oct 15;20(1):104. doi: 10.1186/s12938-021-00941-0.
Walking mechanics recorded with a traditional treadmill may not be the same as the mechanics exhibited during activities of daily living due to constrained walking speeds. Adaptive-speed treadmills allow for unconstrained walking speeds similar to outdoor walking. The aim of this study was to determine differences in kinematic walking parameters of older adults between adaptive-speed treadmill (AST), fixed-speed treadmill (FST) and outdoor walking. We hypothesized that self-selected walking speed (SSWS) during AST walking and outdoor walking would increase compared to FST walking. Furthermore, we hypothesized that AST walking and outdoor walking would increase peak knee flexion, hip flexion, and ankle plantarflexion angles compared to FST walking independent of walking speed changes.
Fourteen older adult participants were asked to complete 3 min of FST and AST walking on a split-belt treadmill. Participants were also asked to complete 6 min of outdoor walking following a circular route in a neighboring park. A wireless inertial measurement unit-based motion capture system was used to record lower extremity kinematics during all walking conditions.
The outdoor walking condition produces significantly higher SSWS compared to FST (p < 0.001) and AST (p = 0.02) conditions. A significantly faster SSWS was exhibited during the AST condition compared to the FST condition (p = 0.026). Significantly higher peak ankle plantarflexion angles are exhibited during the outdoor walking condition compared to the AST (p < 0.001, g = 1.14) and FST (p < 0.001, g = 1.13) conditions after accounting for walking speed. There was a significantly lowered difference between the outdoor walking condition and both AST (p = 0.029, g = 0.49) and FST (p = 0.013, g = 0.63) conditions in peak knee flexion angles after accounting for SSWS. There are no significant differences between outdoor, AST, and FST conditions on peak hip flexion angles. Older adults exhibit changes in peak ankle plantarflexion and peak knee flexion angles during outdoor walking compared to treadmill walking but not between treadmill controller types. We found no differences in the kinematics exhibited by older adults between both AST and FST walking.
Incorporating unconstrained walking speed with the AST while maintaining similar FST sagittal plane kinematics may allow for more translatable conditional balance and walking rehabilitation.
由于行走速度受限，传统跑步机记录的行走力学可能与日常生活活动中的力学表现不同。自适应速度跑步机允许不受限制的行走速度，类似于户外行走。本研究的目的是确定老年人在自适应速度跑步机（AST）、固定速度跑步机（FST）和户外行走之间的运动学行走参数差异。我们假设在 AST 行走和户外行走时，与 FST 行走相比，自我选择的行走速度（SSWS）会增加。此外，我们假设 AST 行走和户外行走会增加峰值膝关节屈曲、髋关节屈曲和踝关节跖屈角度，而与行走速度的变化无关。
14 名老年参与者被要求在分带跑步机上完成 3 分钟的 FST 和 AST 行走。还要求参与者在附近公园的圆形路线上完成 6 分钟的户外行走。使用基于无线惯性测量单元的运动捕捉系统记录所有行走条件下的下肢运动学。
户外行走条件产生的 SSWS 明显高于 FST（p<0.001）和 AST（p=0.02）条件。AST 条件下的 SSWS 明显快于 FST 条件（p=0.026）。在考虑行走速度后，户外行走条件下的峰值踝关节跖屈角度明显高于 AST（p<0.001，g=1.14）和 FST（p<0.001，g=1.13）条件。在考虑 SSWS 后，户外行走条件与 AST（p=0.029，g=0.49）和 FST（p=0.013，g=0.63）条件之间的峰值膝关节屈曲角度差异显著降低。在峰值髋关节屈曲角度方面，户外、AST 和 FST 条件之间没有显著差异。与跑步机行走相比，老年人在户外行走时会改变峰值踝关节跖屈和峰值膝关节屈曲角度，但在跑步机控制器类型之间没有改变。我们没有发现老年人在 AST 和 FST 行走之间的运动学表现有任何差异。
在保持相似的 FST 矢状面运动学的同时，将不受限制的行走速度与 AST 相结合，可能会使更具可转移性的条件平衡和行走康复成为可能。
