A new study shows the combination was best at improving HbA1c levels, compared with either type of exercise alone or no exercise.
Researchers say exercise can provide many health benefits for people with type 2 diabetes, but until now the exact type of exercise to optimize those benefits has been uncertain.
HbA1c is a test that measures blood sugar control for the previous few months. Normal HbA1c is 6% or less. People with diabetes are urged to keep their HbA1c below 7%.
In the study, researchers compared the effects of a nine-month aerobic exercise program, a resistance training program, and combination exercise program vs. not exercising in 262 previously sedentary men and women with type 2 diabetes.
The results showed that improvements in HbA1c levels were greatest among those who were in the combination group. For example, the improvement was -0.34% in the combination exercise group compared with the non-exercisers, while changes in these levels were not significant in those who did aerobic exercise or resistance training alone.
In addition, fewer of the people in the combination exercise group needed to increase the amount of medications they required to control their disease, compared with the other groups. Thirty-nine percent of non-exercisers had to increase these medications compared with 32% in the resistance training group, 22% in the aerobic exercise group, and 18% in the combination group.
2 Types of Exercise Best
"Although both resistance and aerobic training provide benefits, only the combination of the two were associated with reductions in HbA1c levels,” researcher Timothy S. Church, MD, MPH, PhD, of Louisiana State University System in Baton Rouge, La., and colleagues write in the Journal of the American Medical Association.
“It also is important to appreciate that the follow-up difference in HbA1c between the combination training group and the control group occurred even though the control group had increased its use of diabetes medications while the combination training group decreased its diabetes medication uses,” they write.
In an editorial that accompanies the study, Ronald J. Sigal, MD, MPH, of the University of Calgary in Alberta, Canada, and Glen P. Kenny, PhD, of the University of Ottawa and Ottawa Hospital Research Institute in Ottawa, Canada, say the results suggest that people with type 2 diabetes who want to maximize the effects of exercise on their diabetes control should perform both aerobic and resistance exercise.
"Given a specific amount of time to invest in exercise, it is more beneficial to devote some time to each form of exercise rather than devoting all the time to just one form of exercise," they write.