Motl Robert W, Baird Jessica F
University of Illinois Chicago, 1919 W Taylor St, Chicago, IL 60612, USA.
Department of Physical Therapy, University of Alabama at Birmingham, USA.
Mult Scler J Exp Transl Clin. 2021 Nov 23;7(4):20552173211057514. doi: 10.1177/20552173211057514. eCollection 2021 Oct.
Cardiorespiratory fitness (VO) may be a modifiable indicator of health status and well-being in older adults with multiple sclerosis.
We examined differences in VO and moderate-to-vigorous physical activity between older adults with multiple sclerosis and healthy controls, and whether moderate-to-vigorous physical activity accounted for group differences in VO.
Older adults with multiple sclerosis ( = 31) and healthy controls ( = 29) completed a cardiopulmonary exercise test and wore an accelerometer for measuring moderate-to-vigorous physical activity. The data were analyzed using the Baron and Kenny approach for examining moderate-to-vigorous physical activity as a mediator of group differences in VO.
The multiple sclerosis group had significantly lower VO and moderate-to-vigorous physical activity than healthy controls. VO had a large correlation with moderate-to-vigorous physical activity ( = .59). Group initially explained 8% of the variance in VO ( = -0.29). The inclusion of moderate-to-vigorous physical activity accounted for an additional 27% of the variance in VO, but only moderate-to-vigorous physical activity ( = 0.57) was a statistically significant correlate of VO. The effect of Group was attenuated and non-significant with the addition of moderate-to-vigorous physical activity in Step 2 (Group β Step 1 = -0.29, Group β Step 2 = -0.05).
Our results provide initial support for targeting moderate-to-vigorous physical activity as an approach for improving VO in older adults with multiple sclerosis.
心肺适能（VO）可能是患有多发性硬化症的老年人健康状况和幸福感的一个可改变指标。
我们研究了患有多发性硬化症的老年人与健康对照组在VO和中度至剧烈身体活动方面的差异，以及中度至剧烈身体活动是否解释了VO中的组间差异。
患有多发性硬化症的老年人（n = 31）和健康对照组（n = 29）完成了一项心肺运动测试，并佩戴加速度计以测量中度至剧烈身体活动。使用Baron和Kenny方法分析数据，以检验中度至剧烈身体活动作为VO组间差异的中介变量。
多发性硬化症组的VO和中度至剧烈身体活动显著低于健康对照组。VO与中度至剧烈身体活动有很大的相关性（r = 0.59）。组间差异最初解释了VO中8%的方差（β = -0.29）。纳入中度至剧烈身体活动又解释了VO中27%的方差，但只有中度至剧烈身体活动（β = 0.57）是VO的统计学显著相关因素。在第2步中加入中度至剧烈身体活动后，组间差异的效应减弱且无统计学意义（组间差异β第1步 = -0.29，组间差异β第2步 = -0.05）。
我们的结果为将中度至剧烈身体活动作为改善患有多发性硬化症的老年人VO的一种方法提供了初步支持。
