Structured Exercise Training Can Help Control Diabetes

The Journal of the American Medical Association has published a review of available studies to try and clarify the best use of physical activity in diabetes control.  It’s well known that regular exercise improves glucose control in diabetes, but it’s not clear which type of exercise gets the best results. 

Current guidelines recommend that patients with type 2 diabetes do at least 150 minutes weekly of moderate aerobic exercise together with resistance exercises 3 days a week.  But many studies have been reported that don’t follow these guidelines.  To find out if there’s an optimal workout regime for diabetics, Brazilian scientists conducted a meta-analysis of published literature, and reported their results in JAMA.

The selected studies had to be of at least 12 weeks’ duration and follow effects on glycosylated hemoglobin (HbA1c), comparing an exercise regime with a control group. ’Structured exercise regimens’ could include aerobic and/or resistance training, or both, and physical activity advice could be given with or without dietary management.

Of more than 4,000 publications reviewed, 47 randomized controlled trials were selected, covering 8,538 patients.  Structured exercise training (23 studies) was associated with a reduction in HbA1c levels averaging -0.67%.  The reductions for different types of exercise were: structured aerobic exercise -0.73%, structured resistance training -0.57%, and both combined -0.51%.  when the aerobic exercise was more than 150 minutes weekly the HbA1c reduction averaged -0.89%, whereas with 150 minutes a week or less the reduction was only -0.36%.  Physical activity advice combined with dietary advice was associated with -0.58% reduction in HbA1c.

In general, the quality of the studies available for analysis was not very good, according to the authors of the study.  However, the results were sufficiently strong for an accompanying editorialist to write: “[this analysis] provides solid evidence for public policy makers to consider structured exercise and physical activity programs as worthy of insurance reimbursement to promote health, especially in high-risk populations.”  That should help remove one objection patients find to avoid doing a regular exercise program.