The impact of exercise training on fatigue in patients with chronic obstructive pulmonary disease: a systematic review and meta-analysis

Fatigue can be divided in perceived fatigue, the feeling of exhaustion or lack of energy, and performance fatigue, the reduction in muscle force/activation during a given task. This meta-analysis evaluates the impact of exercise training on fatigue, compared with normal care in patients with COPD.

We searched randomised controlled trials on MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials and CINAHL databases from their inception to December, 31st 2019 using the terms COPD, Fatigue, Fatigability, Muscle activation, Muscle endurance, Muscle Performance, Voluntary Activation, Motoneuron excitability, Force Development, Exercise, AND Rehabilitation.

We evaluated 494 potential articles. Sixteen, all evaluating perceived fatigability, satisfied the inclusion criteria and were included. Twelve studies (463 patients) assessed fatigue by the Chronic Respiratory Questionnaire showing that intervention improved significantly more than the control group [SMD 0.708; 95% CI 0.510, 0.907; p < 0.001; I² = 34.3%; p = 0.116]. Two studies (68 patients) using the Fatigue Impact Scale, did not find any significant differences between groups [SMD -0.922; 95%CI -2.258, 0.413; p = 0.176; I² = 83.9%; p = 0.013]. Two studies (82 patients) assessed perceived fatigue by the Fatigue Severity Scale: the intervention improved significantly more than the control group [SMD -2.282; 95%CI -2.870, -1.699; p < 0.001; I² = 64.6%, p = 0.093]. No study evaluating performance fatigue was found.

This study provided low-quality evidence of a positive impact of different exercise training programs on perceived fatigue in patients with COPD. Further studies are needed to assess the effects of exercise training on fatigue and to test tailored programs.