Type 1 diabetics gain guide to filling exercise prescription

Type 1 diabetics gain guide to filling exercise prescription

People living with Type 1 diabetes have long been encouraged to exercise for health benefits. Now they have a guide on how to do so safely and keep their blood sugars in check.

In Type 1 diabetes, the immune system attacks and kills cells in the pancreas, the Canadian Diabetes Association says. Since no or very little insulin is released, people with Type 1 diabetes need to inject insulin.

The Juvenile Diabetes Research Foundation funded the new consensus review by 21 international experts on the best types of exercise, foods to eat and adjustments to insulin and other medications that people with Type 1 diabetes need to make when they work out.

It's published in this week's online issue of The Lancet Diabetes & Endocrinology.

"The first person who discovered that exercise had an effect on blood sugar was a physician who was living with Type 1 diabetes in the early 1920s," said Michael Riddell, a kinesiology professor at York University in Toronto, one of the authors of the review. "He discovered that when he played tennis, that exact same insulin dose was almost double effective at dropping the blood sugar levels compared to when he was sedentary."

Riddell has both professional and personal interests in the topic. He's had Type 1 diabetes since age 14 and enjoys basketball, mountain biking and some tennis and jogging.

But people with Type 1 diabetes have had to rely on trial and error in juggling nutrition and insulin doses to prevent exercise-related fluctuations in their blood sugar.

"The main recommendation in these new consensus guidelines is on what types of carbohydrates to eat and when to eat them, when to monitor your blood sugar," he said in an interview Tuesday.

According to Riddell, it's best to test:

- Twice before you begin to exercise.

- Every 30 minutes during the activity.

- At least 12 hours afterwards, given the lasting impacts of exercise on blood sugar levels on the meal afterwards or at night when you're sleeping.

Regular exercise helps people with both Type 1 and Type 2 diabetes to achieve their blood sugar goals, along with improving risks for cardiovascular disease.

The reviewers estimate about 60 per cent of patients living with Type 1 diabetes are overweight or obese.

For adults with Type 1, Riddell said the exercise prescription is two-fold:

- 150 minutes per week of aerobic physical activity, such as walking, jogging or cycling.

- Resistance exercise like weight training two to three days a week to build up the strength and size of muscles.

The guideline also offers recommendations for aerobic exercise, such as how to lower the insulin dose on the day of the work out. For more intense activities like hockey or mixed martial arts, Riddell said the guide describes how to safely increase the insulin dose to manage the stress associated with those types of exercises.

The document is intended for health-care practitioners, such as physicians, dietitians and sport physiologists who work with those with Type 1 diabetes.

Patients may also find it valuable in tailoring their diabetes management or to take with them when visiting a clinic if they have specific questions, Riddell said.

Several authors said they've received fees from pharmaceutical and medical device makers.