Can exercise limits prevent post-exertional malaise in chronic fatigue syndrome? An uncontrolled clinical trial

Jo Nijs, Freya Almond, Pascale De Becker, Steven Truijen, Lorna Paul

    Research output: Contribution to journalArticle


    Objective: It was hypothesized that the use of exercise limits prevents symptom increases and worsening of their health status following a walking exercise in people with Chronic Fatigue Syndrome (CFS).Design: An uncontrolled clinical trial (semi-experimental design).Setting: Outpatient clinic of a university department.Subjects: 24 patients with CFS.Interventions: Subjects undertook a walking test with the two concurrent exercise limits. Each subject walked at an intensity where the maximum heart rate was determined by heart rate corresponding to the respiratory exchange ratio =1.0 derived from a previous sub-maximal exercise test and for a duration calculated from how long each patient felt they were able to walk.Main outcome measures: The Short Form 36 Health Survey or SF-36, the CFS Symptom List, and the CFS-Activities and Participation Questionnaire were filled in prior to, immediately and 24 hours post-exercise.Results: The fatigue increase observed immediately post-exercise (p=0.006) returned to pre-exercise levels 24 hours post-exercise. The increase in pain observed immediately post-exercise was retained at 24 hours post-exercise (p=0.03). Fourteen of 24 subjects experienced a clinically meaningful change in bodily pain (change of SF-36 bodily pain score ?10). Six of 24 participants indicated that the exercise bout had slightly worsened their health status, and 2 of 24 had a clinically meaningful decrease in vitality (change of SF-36 vitality score ?20). There was no change in activity limitations/participation restrictions.Conclusion: It was shown that the use of exercise limits (limiting both the intensity and duration of exercise) prevents important health status changes following a walking exercise in people with CFS, but was unable to prevent short-term symptom increases.
    Original languageEnglish
    Pages (from-to)426-435
    Number of pages10
    JournalClinical Rehabilitation
    Issue number5
    Publication statusPublished - 1 May 2008



    • exercise limits
    • chronic fatigue syndrome
    • CFS
    • post-exertional malaise
    • uncontrolled clinical trial

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