Acute Effects of Walking, Cycling, and Yoga Exercise on Cognition in Multiple Sclerosis

Background: Cognitive impairment is a highly prevalent, disabling, and poorly-managed consequence of multiple sclerosis (MS). Exercise training represents a promising approach for managing cognitive impairment in this population. However, there is limited evidence supporting an optimal exercise stimulus for improving cognition in MS.

Objectives: The current study compared the acute effects of moderate intensity treadmill walking, moderate intensity cycle ergometry, and guided yoga with quiet rest on executive control in 24 persons with relapsing-remitting MS without impaired cognitive processing speed using a within-subjects, repeated-measures design.

Methods: Participants completed four experimental conditions that consisted of 20 minutes of moderate intensity treadmill walking exercise, moderate intensity cycle ergometer exercise, guided yoga, and quiet rest in a randomized, counter-balanced order. Participants underwent a modified-flanker task as a measure of executive control immediately prior to and following each condition.

Results: Repeated-measures ANOVAs indicated general pre-to-post improvements in reaction time, but not accuracy, on the modified-flanker task for all three exercise modalities compared with quiet rest. However, there were additional, selective pre-to-post reductions in the cost of interfering stimuli on reaction time on the modified-flanker task for treadmill walking (F(1,23)=4.67,p=.04,η_p²=.17), but not cycle ergometry (F(1,23)=0.12,p=.73,η_p²<.01) or guided yoga (F(1,23)=0.73,p=.40,η_p²=.03), compared with quiet rest.

Conclusions: The present results support treadmill walking as the modality of exercise that might exert the largest beneficial effects on executive control in persons with relapsing-remitting MS without impaired cognitive processing speed. This represents an exciting starting point for delineating the appropriate exercise stimulus (i.e., modality and intensity) for inclusion in a subsequent longitudinal exercise training intervention for improving cognitive performance in this population.