Weightlifting First Controls Diabetes

Type 1 diabetes patients may reduce impact of hypoglycemia by lifting weights before aerobic exercise

(RxWiki News) Unlike type 2 diabetes patients, people with type 1 diabetes have to be careful when they exercise. Physical activity can knock their blood sugar levels out of control.

So, is there a way type 1 diabetes patients can safely exercise?

People with type 1 diabetes had better blood sugar control if they lifted weights before aerobic exercise, compared to those who did aerobic exercise before weightlifting.

"Talk with your doctor to formulate an exercise plan for diabetes."

In a recent study, Ronald J. Sigal, M.D., M.P.H., of the Ottawa Hospital Research Institute and the University of Calgary, and colleagues looked at how exercise order might affect blood sugar control in people with type 1 diabetes.

Type 1 is a form of diabetes in which the body does not produce enough insulin, a natural hormone that helps manage blood sugar in the body.

While exercise is a major part of managing diabetes, people with type 1 diabetes face the risk of hypoglycemia (dangerously low blood sugar levels) after exercise. Extremely low blood sugar puts patients at risk of all sorts of complications, even coma.

Dr. Sigal and colleagues wanted to see if the order of exercises would protect against the risk of these dangerous drops in blood sugar.

They found that doing resistance exercise (lifting weights) before aerobic exercise (cardio) improved the stability of blood sugar levels throughout exercise.

On top of that, lifting weights before aerobic exercise reduced the length and intensity of hypoglycemia after exercise.

This order of exercise is not a new concept. Otherwise healthy athletes are generally told to do resistance exercises before their aerobic workouts.

As fitness expert Jim Crowell, owner and head trainer of Integrated Fitness, explains, "I almost always do our strength training and explosive training first before I do our aerobic training. The reasons behind this have been well researched by coaches and scientists, but from a lay person's perspective our bodies need to hold intensity to receive the optimal training effect. When we do heavier strength work our body has to hold the correct postures and positions while managing heavier weight and if we are tired we won't be able to hit the positions properly.

"Also, moving heavier weights requires a lot of energy from the muscles and the central nervous system," he continues. "So, to perform the movements properly you have to have adequate energy to 'explode' the movement well. After you have done your high energy system work, you can move into more aerobic and cyclical movement and maintain a sub-max energy output for longer periods of time. When you sequence the training session that way you can achieve both a strength/explosive training effect along with an aerobic effect on top of it."

For their study, the researchers recruited 12 patients with type 1 diabetes. These patients went to two exercise sessions. During one session, they did aerobic exercise for 45 minutes, followed by weightlifting for 45 minutes. In another session, the participants lifted weights before aerobic exercise.

Patients who did aerobic exercise first had bigger drops in blood sugar levels during exercise, compared to those who lifted weights first.

Even though the order of exercise did not increase the risk of hypoglycemia, the length and severity of hypoglycemia was greater when doing aerobic exercise before weightlifting. Yet, this difference was only slight.

This study's findings suggest that the order of exercise may have an effect on blood sugar control. However, the study was small and found only minor differences in blood sugar control between the two exercise orders.

More research is needed before it can be said definitively that exercise order impacts the risk of hypoglycemia. Future studies may need to involve more patients doing a larger variety of exercises.

The results of this current study are published in Diabetes Care, a journal of the American Diabetes Association. 

Review Date: 
March 12, 2012