Health-related effects of worksite interventions involving physical exercise and reduced workhours

Objectives This study examined the health-related effects of two worksite interventions, physical exercise and reduced workhours, on women employed in dentistry. Methods Six workplaces were randomized to one of the following three conditions: (i) 2.5 hours of weekly, mandatory physical exercise of middle-to-high intensity to be performed during workhours (N=62), (h) a reduction of full-time weekly workhours from 40 to 37.5 hours (N=50), and (iii) reference. In all, 177 women participated. Biomarkers and self-ratings in questionnaires were obtained before the intervention (T-1), and six (T-2) and 12 months (T-3) after the intervention. Results The results showed increased levels of physical activity and exercise in all of the groups, the level of physical exercise being significantly greater in the physical exercise group. Repeated-measures analyses of variance using data from T-1 and T-3 for biological measures and all three time points for self-ratings produced significant interaction effects for glucose, waist-to-hip ratio, and work ability and clear trends for general symptoms and upper-extremity disorders. Posthoc analyses showed that the results of the health-related measures differed between the interventions, decreased glucose and upper-extremity disorders in the exercise group, and increased high-density lipoprotein and waist-to-hip ratio among those working reduced hours. Conclusions These results show that the two interventions had small and varied effects on biomarkers and self-reports of different aspects of health among women. It is suggested that interventions involving a modest reduction in workhours; seem to be more effective if these hours are used for physical exercise.