Testing a workplace physical activity intervention: a cluster randomized controlled trial
1 Yorkshire Quality and Safety Research Group, Bradford Institute for Health Research, Bradford Teaching Hospitals NHS Foundation Trust, Bradford, UK
2 Institute for Psychological Sciences, University of Leeds, Leeds, UK
3 School of Healthcare, University of Leeds, Leeds, UK
4 Academic Unit of Health Economics, Leeds Institute of Health Sciences, University of Leeds, Leeds, UK
5 Division of Biostatistics, Leeds Institute of Genetics, Health and Therapeutics, Leeds, University of Leeds
International Journal of Behavioral Nutrition and Physical Activity 2011, 8:29 doi:10.1186/1479-5868-8-29Published: 11 April 2011
Increased physical activity levels benefit both an individuals' health and productivity at work. The purpose of the current study was to explore the impact and cost-effectiveness of a workplace physical activity intervention designed to increase physical activity levels.
A total of 1260 participants from 44 UK worksites (based within 5 organizations) were recruited to a cluster randomized controlled trial with worksites randomly allocated to an intervention or control condition. Measurement of physical activity and other variables occurred at baseline, and at 0 months, 3 months and 9 months post-intervention. Health outcomes were measured during a 30 minute health check conducted in worksites at baseline and 9 months post intervention. The intervention consisted of a 3 month tool-kit of activities targeting components of the Theory of Planned Behavior, delivered in-house by nominated facilitators. Self-reported physical activity (measured using the IPAQ short-form) and health outcomes were assessed.
Results and discussion
Multilevel modelling found no significant effect of the intervention on MET minutes of activity (from the IPAQ) at any of the follow-up time points controlling for baseline activity. However, the intervention did significantly reduce systolic blood pressure (B = -1.79 mm/Hg) and resting heart rate (B = -2.08 beats) and significantly increased body mass index (B = .18 units) compared to control. The intervention was found not to be cost-effective, however the substantial variability round this estimate suggested that further research is warranted.
The current study found mixed support for this worksite physical activity intervention. The paper discusses some of the tensions involved in conducting rigorous evaluations of large-scale randomized controlled trials in real-world settings.
Current controlled trials ISRCTN08807396