Fatigue scores in people with multiple sclerosis. Error bars represent standard deviations. Higher scores represent greater fatigue levels. Exercisers represent individuals who reported participating in at least two, 30-min exercise sessions·wk-1, or had a physical activity score in the leisure domain of the International Physical Activity Questionnaire greater than 600 MET-min·wk-1. * Exercisers significantly different from non-exercisers, p < 0.05. ** Exercisers significantly different from Non-exercisers, p < 0.001.