Effect of physical exercise on musculoskeletal pain in multiple body regions among healthcare workers: Secondary analysis of a cluster randomized controlled trial.

BACKGROUND While physical exercise is beneficial for back and neck-shoulder pain, only few intervention studies have evaluated effects on pain in multiple body regions. Furthermore, direct measurement of pain threshold can provide additional information to self-reported pain intensity. OBJECTIVES To evaluate the effect of workplace versus home-based physical exercise on pressure pain threshold (PPT) and musculoskeletal pain intensity in multiple body regions. STUDY DESIGN Secondary analysis of an examiner-blinded, cluster randomized controlled trial with allocation concealment. METHOD Two-hundred female healthcare workers from 18 departments at three hospitals were cluster-randomized to 10 weeks of: 1) home-based physical exercise (HOME) performed alone during leisure time for 5 × 10 min per week or 2) workplace physical exercise (WORK) performed in groups during working hours for 5 × 10 min per week and up to 5 motivational coaching sessions. PPT (neck, lower back, lower leg) and perceived pain intensity in multiple body regions (feet, knee, hips, lower and upper back, elbow, hand, shoulder, neck, and head) were measured at baseline and 10-week follow-up. RESULTS In some of the body regions, PPT and pain intensity improved more following WORK than HOME. Between-group differences at follow-up (WORK vs. HOME) were 41 kPA [95% CI 13-70, effect size (ES): 0.22] for PPT in the lower back, and -0.7 [95% CI -1.0-0.3, ES: 0.26] and -0.6 points [95% CI -0.9--0.2, ES: 0.23] for pain intensity in the lower back and feet, respectively. HOME did not improve more than WORK for any of the measurements. CONCLUSION Physical exercise recommendations for healthcare workers should consider the setting, i.e. performing supervised group-based exercise at work and motivational coaching sessions is more effective than exercising alone at home.