Sources of Variability in Physical Activity Among Inactive People with Multiple Sclerosis
Evidence supports that physical activity (PA) improves symptoms of multiple sclerosis (MS). Although application of principles from Social Cognitive Theory (SCT) may facilitate positive changes in PA behaviour among people with multiple sclerosis (pwMS), the constructs often explain limited variance in PA. This study investigated the extent to which MS symptoms, including fatigue, depression, and walking limitations combined with the SCT constructs, explained more variance in PA than SCT constructs alone among pwMS.
Baseline data, including objectively assessed PA, exercise self-efficacy, goal setting, outcome expectations, 6-min walk test, fatigue and depression, from 65 participants of the Step It Up randomized controlled trial completed in Ireland (2016), were included. Multiple regression models quantified variance explained in PA and independent associations of (1) SCT constructs, (2) symptoms and (3) SCT constructs and symptoms.
Model 1 included exercise self-efficacy, exercise goal setting and multidimensional outcomes expectations for exercise and explained ~14% of the variance in PA (R 2=0.144, p < 0.05). Model 2 included walking limitations, fatigue and depression and explained 20% of the variance in PA (R 2=0.196, p < 0.01). Model 3 combined models 1 and 2 and explained variance increased to ~29% (R 2=0.288; p<0.01). In Model 3, exercise self-efficacy (β=0.30, p < 0.05), walking limitations (β=0.32, p < 0.01), fatigue (β = −0.41, p < 0.01) and depression (β = 0.34, p < 0.05) were significantly and independently associated with PA.
Findings suggest that relevant MS symptoms improved by PA, including fatigue, depression and walking limitations, and SCT constructs together explained more variance in PA than SCT constructs alone, providing support for targeting both SCT constructs and these symptoms in the multifactorial promotion of PA among pwMS.
KeywordsMultiple sclerosis Physical activity Social cognitive correlates Symptoms
Compliance with Ethical Standards
This work is supported by the Irish Health Research Board, Health Research Award, grant number HRA_PHR/2013–264.
Conflict of Interest
No commercial party having a direct financial interest in the results of the research supporting this article or will be confer a benefit on the authors or on any organisation with which the authors are associated.
All procedures in this study were in accordance with ethical standards of the institutionaal and/or national research committee and with the 1964 Helsinki declaration and its later ammendments or comarable ethical standards.
Informed consent was obtained from all individual participants included in the study.
- 1.Platta ME, et al. Effect of exercise training on fitness in multiple sclerosis: a meta-analysis. Arch Phys Med Rehabil. 2016;16(16):00091–5.Google Scholar
- 4.Casey B, et al. Modifiable psychosocial constructs associated with physical activity behaviour in people with multiple sclerosis: a systematic review and meta-analysis. Mult Scler J. 2016;22(S3):29–30.Google Scholar
- 5.Uszynski MK, Casey B, Hayes S, Gallagher S, Purtill H, Motl RW, et al. Social cognitive theory correlates of physical activity in inactive adults with multiple sclerosis. Int J MS Care. 2017.Google Scholar
- 9.Coote S, et al. A randomised controlled trial of an exercise plus behaviour change intervention in people with multiple sclerosis: the step it up study protocol. BMC Neurol. 2014;14(241):014–0241.Google Scholar
- 21.Wood B, et al. Prevalence and concurrence of anxiety, depression and fatigue over time in multiple sclerosis. Mult Scler. 2012:1352458512450351.Google Scholar