Physical inactivity, neurological disability, and cardiorespiratory fitness in multiple sclerosis

Objective - We examined the associations among physical activity, neurological disability, and cardiorespiratory fitness in two studies of individuals with multiple sclerosis (MS). Method - Study 1 included 25 women with relapsing-remitting MS (RRMS) who undertook an incremental exercise test for measuring peak oxygen ((V) over dotO(2peak)) consumption, wore an accelerometer during a 7-day period, and completed the Godin Leisure-Time Exercise Questionnaire (GLTEQ). Study 2 was a follow-up of Study 1 and included 24 women with RRMS who completed the self-reported Expanded Disability Status Scale (EDSS), undertook an incremental exercise test, wore an accelerometer during a 7-day period, and completed the GLTEQ. Results - Study 1 indicated that (V) over dotO(2peak) was significantly correlated with accelerometer counts (pr = 0.69) and GLTEQ scores (pr = 0.63) even after controlling for age and MS duration. Study 2 indicated that (V) over dotO(2peak) was significantly correlated with accelerometer counts (pr = 0.50), GLTEQ scores (pr = 0.59), and EDSS scores (pr = -0.43) even after controlling for age and MS duration; there was a moderate partial correlation between accelerometer counts and EDSS scores (pr = -0.43). Multiple linear regression analysis indicated that both accelerometer counts (beta = 0.32) and EDSS scores (beta = -0.40) had statistically significant associations with (V) over dotO(2peak). Conclusion - The findings indicate that physical inactivity and neurological disability might represent independent risk factors for reduced levels of cardiorespiratory fitness in this population.