The role of fatigue in the associations between exercise and psychological health in Multiple Sclerosis: Direct and indirect effects

This research aims to investigate the direct and indirect effects of physical training on psychological health in a sample of individuals with Multiple Sclerosis (MS). Thirty-five women affected by relapsing-remitting MS, with a mean age of (40 ± 5) years and an Expanded Disability Status Scale (EDSS) score ranging between 0 and 3, participated in the study. After baseline tests, in accordance with pairing techniques, participants were assigned to an experimental (EG) and a control group (CG). The EG attended a 12-week combined aerobic and strength program. Those in the EG and the CG were homogeneous at baseline and were treated similarly except for the intervention. Participants of both groups were tested before and after the intervention with the following instruments: 1. Modified Fatigue Impact Scale (MFIS); 2. Beck Depression Inventory scale (BDI); 3. Multiple Sclerosis Quality of life–54 (MSQOL-54). Data was analyzed with non-parametric tests for unpaired samples, linear regression and mediation analysis. The results showed: (a) the benefits of physical training on the perception of fatigue, depression, social activity and Quality of Life (QoL) in the EG; (b) the role of fatigue as a mediator of the relationship between participation in physical training and depression, social activity and QoL. Findings suggested the effectiveness of a combined aerobic and strength training for the improvement of psychological aspects in women affected by MS and the mediation role of fatigue in such a relationship.