Effects of a self-regulation based physical activity program (the “4-STEPS”) for unexplained chronic fatigue : A randomized gontrolled trial

Background: This study aimed at assessing the effects of a self-regulation-based brief physical activity program for patients suffering from unexplained chronic fatigue, the “4- STEPS to control your fatigue program”. Method: A 12-week randomized controlled trial was conducted. Adult patients meeting the CDC criteria for idiopathic chronic fatigue were randomized to either the control condition (standard care) or the intervention condition (4-STEPS). The 4-STEPS was based on self-regulation principles and consisted of motivational interviewing and self-regulation skills training. All patients were assessed at baseline and post-treatment (12 weeks) for fatigue severity (primary outcome) and impact, physical activity (leisure time physical activity, number of daily steps and personal activity goal progress), health-related quality of life, somatic distress and psychological distress (depression and anxiety). Results Ninety-one patients (45 intervention and 46 control patients) received the allocated intervention. At post-treatment, statistical analysis revealed a significant difference for subjective experience of fatigue (4.73 points; g=0.51) in favour of the intervention group. Mixed design ANCOVAs showed a significant effect of the 4-STEPS on fatigue severity, leisure time physical activity, personal activity goal progress and healthrelated quality of life. No significant effects were found for number of daily steps and somatic and psychological distress. Conclusion: The 4-STEPS program has significant beneficial effects at post-treatment. This brief self-regulation-based intervention looks promising for the management of unexplained chronic fatigue.Fundação para a Ciência e Tecnologia (FCT