Experts agree that exercise is highly beneficial to health. But what are the most cost-effective ways for public health officials and other policymakers on limited budgets to encourage people to exercise?
A team of researchers led by USC Viterbi School of Engineering assistant professor Shinyi Wu has completed a large-scale study of the problem, analyzing 91 worldwide “interventions” to promote exercise. The interventions ranged from painting children’s playgrounds to home visits by counselors.
The interventions were described in more than 5,500 publications analyzed by Wu and her team.
In quantifying the results, the measure of exercise chosen was the MET-hour – the amount of energy consumed in one hour by an individual who is idle. According to this measurement, each person consumes 24 MET-hours per day without exercise. For good health, adults should exercise at least 25.5 MET hours, eliminating 1.5 hours of inactivity. Children need to double this figure to three MET hours.
The researchers used the descriptions to calculate the gain in MET hours produced by each program, multiplying the number of participants motivated by the program by the average MET hour gain produced by each program per day. They divided this figure by the program’s cost to create rankings in terms of exercise gain per dollar per person per day.
A paper titled “Economic Analysis of Physical Activity Interventions,” published in the American Journal of Preventive Medicine, contains a comparison of 17 programs that illustrates a range of interventions and effectiveness.
The paper noted a necessity for more quantitative work by policymakers. “Future interventions to promote physical activity should take care to report resources utilized and costs. Given the large task of increasing physical activity among a sedentary population, a wide variety of options are needed to enhance the likelihood of adoption among disparate target populations.”
Wu, a member of the Daniel J. Epstein Department of Industrial and Systems Engineering, began the study at the RAND Corp., and completed it at USC. Her co-authors at RAND included Deborah Cohen, Yuyan Shi, Marjorie Pearson and Roland Sturm.
The National Cancer Institute funded the study.