Effects of a physical exercise intervention on employees' perceptions of quality of life: a randomized controlled trial

Objectives: To determine the effects of an exercise intervention in workplace health promotion, WHO multidimensional quality of life was chosen as the main outcome variable. Secondary outcomes were different physical fitness indicators. Methods: 110 employees (83 male, 27 female, modus age group 36-45 years) volunteered to participate and were randomly allocated to intervention (n = 52) or control group (n = 58). Intervention subjects exercised 13 weeks, at leisure time, in off-worksite training facilities. Outcome measures were assessed before and after the intervention, and at 3 month follow-up. Results: Significant training effects resulted for overall perception of quality of life, and for psychological and physical health sub-domains. Physical strength indicators improved significantly as well, with these changes being independent from psychological health benefits. At follow-up, elevated psychological scores held steady only for those who continued to exercise on their own. Discussion: This intervention had impact on important health indicators. Since it was arranged on top of a "real world" occupational health promotion program, the observed findings should even more encourage employers to invest in their employees' health.