The Impact of Exercise on Mood, Social and Cognitive Outcomes

Abstract

While the physical health benefits of exercise are well established, mental health benefits remain unclear. The literature reports reduced stress and improved cognitive function in rodent exercise studies, and improved mood scores in humans. However, though mood disorders are characterized by poor response to treatment, studies rarely evaluate difficult-to-treat patients or functional outcomes. Therefore, we evaluated the impact of 12-week, group-based exercise programs (running or yoga) on mood and functional outcomes including health-related quality of life (HRQOL) and social and cognitive functioning. Methods: Study 1 was a retrospective review of mood and stress outcomes in participants with difficult-to-treat mood disorders. In Study 2, we measured functional outcomes before and after the running program in a subsample from Study 1. Improved friendship and high injury rates in the running group inspired Study 3, a randomized control trial to evaluate mood and functional outcomes in a non-clinical sample using yoga, a low-impact exercise program that included cognitive control. Results: In Study 1 (n=46), depression (p<0.0001) and stress (p=0.01) scores improved over time, and improved friendship levels were predictive of improved mood scores (p<0.04). In Study 2 (n=18), we found improved scores on several HRQOL subscales, including social functioning (p-values<0.01) and weak improvements in working memory and processing speed (p-values<0.04). In Study 3, yoga participants (n=20) had improved stress (p=0.02), loneliness (p=0.002), and HRQOL (p-values<0.03) scores, compared to wait-list controls (n=8). Yoga participants improved on tasks reflecting hippocampal memory (p-values<0.006) and attention and inhibitory control (p=0.03). Regression and mediation analyses suggest that social support mediates the stress-reducing impact of yoga (p-values<0.0005). Discussion: Group-based exercise programs impart benefits across mental health and functional outcomes for participants with and without mood disorders. Exercise may be an effective adjunctive treatment for mood disorders, and more data is needed on how social support impacts clinical outcomes.