title: Efficacy of an exercise intervention for employees with work-related fatigue: study protocol of a two-arm randomized controlled trial.
abstract: BACKGROUND
  The aim of the current study is to evaluate the efficacy of an exercise intervention to reduce work-related fatigue. Exercise is a potentially effective intervention strategy to reduce work-related fatigue, since it may enhance employees' ability to cope with work stress and it helps to detach from work. However, based on available research, no clear causal inferences regarding its efficacy can be made. This RCT therefore investigates whether exercise is effective in reducing work-related fatigue, and in improving other indicators of employees' mental and physical well-being and performance.
  
  
  METHODS
  A two-arm parallel trial will be conducted. Participants (N = 108) who experience high levels of work-related fatigue will be randomized at a 1:1 ratio to a 6-week exercise intervention or wait list (control). The exercise intervention consists of three one-hour low-intensity outdoor running sessions a week. Each week, two sessions take place in a group under supervision of a trainer, and one session is completed individually. The running sessions will be carried out during leisure time. The primary outcome is work-related fatigue. Secondary outcomes include work ability, self-efficacy, sleep quality, cognitive functioning, and aerobic fitness. These data will be collected at pre-intervention, post-intervention, and at 6 weeks and 12 weeks after the intervention. In addition, weekly measures of employees' well-being, and exercise activities (i.e. type, frequency, and duration) and experiences (i.e. pleasure, effort, and detachment) will be collected during the intervention period.
  
  
  CONCLUSIONS
  This study will compare an exercise intervention to a wait list. This enables us to examine the effect of exercise on work-related fatigue compared to the natural course of these symptoms. As such, this study contributes to a better understanding of the causal link between exercise and work-related fatigue. If the intervention is proven effective, the results could provide a basis for future 'effectiveness' trials in which the (implementation of the) intervention can be investigated among a broader defined population in a less standardized way, eventually leading to better evidence-based policies and practices to employees, employers, health practitioners, and policy makers concerning the effect of exercise on work-related fatigue.
  
  
  BACKGROUND
  NTR5034. Registered 10 March 2015.
authors.affiliation: Behavioural Science Institute, Radboud University, P.O. Box 9104, 6500 HE, Nijmegen, The Netherlands. j.devries@psych.ru.nl.
authors.forename: Juriena D
authors.initials: JD
authors.lastname: de Vries
authors.affiliation: Behavioural Science Institute, Radboud University, P.O. Box 9104, 6500 HE, Nijmegen, The Netherlands. m.vanhooff@psych.ru.nl.
authors.forename: Madelon L M
authors.initials: ML
authors.lastname: van Hooff
authors.affiliation: Behavioural Science Institute, Radboud University, P.O. Box 9104, 6500 HE, Nijmegen, The Netherlands. s.geurts@psych.ru.nl.
authors.forename: Sabine A E
authors.initials: SA
authors.lastname: Geurts
authors.affiliation: Behavioural Science Institute, Radboud University, P.O. Box 9104, 6500 HE, Nijmegen, The Netherlands. m.kompier@psych.ru.nl.
authors.forename: Michiel A J
authors.initials: MA
authors.lastname: Kompier
mesh_terms: D000223:Adaptation, Psychological; D000328:Adult; D015444:Exercise; D005081:Exercise Therapy / Q000379:methods*; D005221:Fatigue / Q000209:etiology / Q000517:prevention & control*; D005260:Female; D006801:Humans; D007537:Isometric Contraction; D008297:Male; D009784:Occupational Diseases / Q000150:complications / Q000517:prevention & control*; D020377:Self Efficacy; D014940:Work Schedule Tolerance