It has long been known that exercise can have substantial benefits for people with diabetes — both Type 1 and Type 2. It can increase insulin sensitivity, improve cardiovascular fitness, and help sustain weight loss. A common and desired outcome of exercise programs is a lower HbA1c level — particularly for Type 2 diabetes, in which case exercise alone may reduce blood glucose levels. As the number of people with Type 2 diabetes continues to rise — along with its associated medical costs — exercise programs may be an important and currently underused tool in the service of public health, and public finances. But how can the benefits of exercise be extended to the greatest possible number of people? And what does it take to achieve meaningful HbA1c reductions?
Over the years, different studies have explored the potential benefits of a wide variety of exercise programs in people with Type 2 diabetes. The authors of a clinical review published last week attempted to distill the results of these studies. Published in the Journal of the American Medical Association, the review examined 47 clinical trials from 1980 to the present. Of these 47 studies, 23 measured the impact of assigning participants to a structured exercise program; the other 24 tested the effect of giving out exercise advice (often in combination with other advice). Each study lasted at least 12 weeks. Overall, structured exercise programs won out over exercise advice, with an average HbA1c reduction of 0.67% compared with the control group in each study; exercise advice saw an average drop of 0.43% compared with each control group.
Within structured exercise programs, aerobic exercise programs had the best result, with an average HbA1c reduction of 0.73% compared with control groups; resistance programs saw a 0.57% drop, while programs that combined both cardio and resistance saw only a 0.51% drop. Among all structured exercise programs, those that demanded more than 150 minutes of exercise each week were associated with a 0.89% drop in HbA1c; those that demanded 150 minutes or less led to a 0.36% drop. In the separate category of exercise advice, only exercise advice combined with dietary advice was found to reduce HbA1c, with an average reduction of 0.58%; exercise advice alone had no net effect, leading to the overall 0.43% HbA1c drop associated with exercise advice.
A Reuters article on the review notes that to confirm the superiority of structured exercise programs over exercise advice, there would need to be a study directly comparing the two. Nevertheless, it makes intuitive sense that people would be more likely to exercise under supervision than if left to their own devices. The article also notes that such exercise programs may be able to help slow the growth of health-care costs associated with diabetes and prediabetes, which are projected to rise from $194 billion to almost $500 billion in the United States by the end of the decade.
What do you think — should health insurance plans cover exercise programs as a treatment for Type 2 diabetes or prediabetes? If so — and if they are shown to save money — should they cover exercise programs or gym memberships for everyone, or everyone over a certain age? Should doctors fill out prescriptions for exercise programs, just as they do for drugs? Do you believe you would exercise more if you were enrolled in a supervised program at no cost? Have you already tried a structured exercise program designed to combat diabetes? Leave a comment below!