Cochrane analysts examined five randomized, controlled trials of the efficacy of exercise therapy for Chronic Fatigue Syndrome (CFS) and found that after 12 weeks, those receiving exercise therapy were less fatigued than the control participants (SMD -0.77, 95% CIs -1.26 to -0.28).  Additionally, physical functioning was significantly improved with exercise therapy (SMD -0.64, CIs -0.96 to -0.33) but there were more dropouts with exercise therapy (RR 1.73, CIs 0.92 to 3.24). 

Depression trended toward improvement in the exercise therapy group as compared to the control group at 12 weeks (WMD -0.58, 95% CIs -2.08 to 0.92).  Participants receiving exercise therapy were less fatigued than those receiving the antidepressant fluoxetine (Prozac) at 12 weeks (WMD -1.24, 95% CIs -5.31 to 2.83). Participants receiving the combination of the two interventions, exercise + fluoxetine, were less fatigued than those receiving exercise therapy alone at 12 weeks, although, again, the difference did not reach significance (WMD 3.74, 95% CIs -2.16 to 9.64).

When exercise therapy was combined with patient education, those receiving the combination were less fatigued than those receiving exercise therapy alone at 12 weeks (WMD 0.70, 95% CIs -1.48 to 2.88).

The reviewers conclude that there is encouraging evidence that some patients may benefit from exercise therapy and no evidence that exercise therapy may worsen outcomes on average.  Patients with CFS who are similar to those in these trials should be offered exercise therapy, and their progress monitored. 

Citation:  Edmonds M, McGuire H, Price JExercise therapy for chronic fatigue syndrome. Cochrane Database Syst Rev. 2004; (3):CD003200