From the Department of Kinesiology and Community Health, University of Illinois at Urbana-Champaign, Urbana, Illinois (IMR); and Department of Physical Therapy, University of Alabama at Birmingham, Birmingham, Alabama (BJ, SLS, RWM).
Am J Phys Med Rehabil. 2021 Mar 1;100(3):292-296. doi: 10.1097/PHM.0000000000001618.
There is evidence that manual wheelchair users are among the least physically active in society. However, the current cut points for quantifying physical activity intensity based on steps per minute have been developed for ambulatory adults from the general population and other clinical populations and may not be appropriate or applicable for manual wheelchair users. This study examined the association between push rate (an analog of step rate) and energy expenditure across three speeds of treadmill wheelchair propulsion among manual wheelchair users and further generated a push-rate cut point for quantifying moderate-to-vigorous physical activity. Persons who used manual wheelchairs (N = 17) performed three, 6-min bouts of manual wheelchair propulsion on a motor-driven treadmill at speeds of 0.7, 1.3, and 2.0 m/sec. Push rate per trial was measured using SMARTwheels, and the rate of oxygen consumption per trial was measured using a portable metabolic system. The mean (SD) R2 value for the relationship between push rate and energy expenditure was 0.78 (0.14). The mean (SD) push-rate cut point for quantifying moderate-to-vigorous physical activity was 55.05 (26.06) pushes/min. This preliminary study provides the first push-rate cut point for quantifying moderate-to-vigorous physical activity among a heterogeneous sample of manual wheelchair users. This threshold may be important for public health promotion and individual-level monitoring and prescription of free-living physical activity behavior among manual wheelchair users.
有证据表明，手动轮椅使用者是社会中身体活动最少的人群之一。然而，目前基于每分钟步数来量化身体活动强度的截止值是为普通人群和其他临床人群中的步行成年人制定的，可能不适用于或不能用于手动轮椅使用者。本研究考察了在手动轮椅使用者以三种跑步机推进速度推进轮椅时，推频（步频的类似物）与能量消耗之间的关系，并进一步生成了用于量化中等到剧烈身体活动的推频截止值。使用手动轮椅的人员（N=17）在电动跑步机上以 0.7、1.3 和 2.0 m/sec 的速度进行了三次 6 分钟的手动轮椅推进试验。使用 SMARTwheels 测量每次试验的推频，使用便携式代谢系统测量每次试验的耗氧量。推频与能量消耗之间关系的平均（SD）R2 值为 0.78（0.14）。用于量化中等到剧烈身体活动的平均（SD）推频截止值为 55.05（26.06）推/分钟。这项初步研究为异质的手动轮椅使用者群体提供了量化中等到剧烈身体活动的第一个推频截止值。该阈值对于手动轮椅使用者的公共健康促进以及对自由生活身体活动行为的个体水平监测和处方可能很重要。
