MacGillivray Megan K, Lam Tania, Klimstra Marc, Zehr E Paul, Sawatzky Bonita J
a International Collaboration on Repair Discoveries , Vancouver , Canada.
b Rehabilitation Sciences, University of British Columbia , Vancouver , Canada.
Disabil Rehabil Assist Technol. 2018 Apr;13(3):287-292. doi: 10.1080/17483107.2017.1323965. Epub 2017 May 9.
To determine the ecological validity of using able-bodied participants to perform a 10-min wheeling trial by (1) evaluating changes in biomechanics over the trial in manual wheelchair users and able-bodied participants naïve to wheeling and (2) describing differences in changes and variability between groups.
Manual wheelchair users (n = 7, 2-27 years' experience) and able-bodied participants (n = 11) wheeled for 10 min. Kinetic and temporal variables were collected and averaged over each minute, while wheeling strategy (movement pattern) was categorized at minutes 1 and 10.
There was a main effect of time for push angle, and a main effect of group for average push angle, tangential force and total force. Manual wheelchair users used larger push angles and forces compared to able-bodied participants. Surprisingly, intercycle variability did not differ between groups.
Using able-bodied participants to represent manual wheelchair users performing a 10-min wheeling trial is not ecologically valid and caution should be used when interpreting push angle and forces applied to the pushrim. Considering that push angle was the only variable that demonstrated a main effect of time, long durations (e.g., 10 min) of wheeling may be appropriate for use in study designs acknowledging potential changes in wheeling strategy and push angle. Implications for Rehabilitation Some experienced wheelchair users and non-wheelchair users modify their movement pattern from an arc to a circular pattern within a 10-min wheeling trial. There are clear biomechanical differences in push angle and forces applied to the pushrim between wheelchair users with experience and able-bodied non-wheelchair users. Able-bodied participants who have no prior manual wheeling experience are no more variable than long-term wheelchair users. Variability may play an important role in wheelchair propulsion.
通过（1）评估手动轮椅使用者和初次使用轮椅的健全参与者在试验过程中的生物力学变化，以及（2）描述两组之间变化和变异性的差异，来确定使用健全参与者进行10分钟轮椅推动试验的生态效度。
手动轮椅使用者（n = 7，有2 - 27年经验）和健全参与者（n = 11）进行10分钟的轮椅推动。收集每分钟的动力学和时间变量并求平均值，同时在第1分钟和第10分钟对轮椅推动策略（运动模式）进行分类。
推动角度存在时间主效应，平均推动角度、切向力和总力存在组间主效应。与健全参与者相比，手动轮椅使用者使用更大的推动角度和力量。令人惊讶的是，两组之间的周期间变异性没有差异。
使用健全参与者来代表进行10分钟轮椅推动试验的手动轮椅使用者在生态上是无效的，在解释施加在轮辋上的推动角度和力量时应谨慎。考虑到推动角度是唯一显示出时间主效应的变量，较长时间（如10分钟）的轮椅推动可能适用于承认轮椅推动策略和推动角度潜在变化的研究设计。康复意义 一些有经验的轮椅使用者和非轮椅使用者在10分钟的轮椅推动试验中会将他们的运动模式从弧形改为圆形。有经验的轮椅使用者和健全的非轮椅使用者在施加在轮辋上的推动角度和力量方面存在明显的生物力学差异。没有先前手动轮椅推动经验的健全参与者与长期轮椅使用者相比变异性并不更大。变异性可能在轮椅推进中起重要作用。
