A recent study suggests that aerobic exercise training (via improving cardiorespiratory fitness) might improve cognitive processing speed in persons with multiple sclerosis (MS), independent of the influence of depression, pain, and fatigue. Such results further suggest that having elevated depressive symptoms or severe MS-related fatigue might not affect aerobic exercise training-related changes in cognitive processing speed, and that psychological symptoms might not distort the association between aerobic exercise training and changes in cognitive processing speed. 62 persons across the MS disability spectrum completed anxiety, depression, pain, and fatigue questionnaires; underwent Symbol Digit Modalities Test administration; as well as 2 separate incremental exercise tests to exhaustion for measurement of psychological symptoms, cognitive processing speed, and cardiorespiratory fitness, respectively. Researchers found:
- Depressive symptoms, pain, and fatigue were significantly and jointly associated with cardiorespiratory fitness and cognitive processing speed based on bivariate correlation analyses.
- Despite those associations, hierarchical linear regression, bivariate correlation, and partial correlation analyses indicated that those psychological symptoms were not mediators, moderators, or confounders of the cardiorespiratory fitness/cognitive processing speed relationship, respectively.
Sandroff BM, Pilutti LA, Motl RW. Cardiorespiratory fitness and cognitive processing speed in multiple sclerosis: The possible roles of psychological symptoms. [Published online ahead of print October 3, 2018]. Mult Scler Relat Disord. doi:10.1016/j.msard.2018.09.033.