Dr. Beth Taylor, director of Exercise Physiology Research at Hartford Hospital, discusses how exercise helps regulate glucose levels in the body and how this is beneficial to patients with diabetes. November is American Diabetes month.
We all know exercise is extremely important in leading a healthy lifestyle, but how does exercise specifically help patients with diabetes?
Exercise does two really important things for patients with diabetes. The first is that it mobilizes a pool of glucose receptors that are insulin independent. These receptors then facilitate glucose uptake into cells, which lower blood glucose. No insulin needed! Since diabetes is characterized by high blood glucose and either insufficient insulin production or insulin insensitivity, being able to lower blood glucose without insulin release is a great therapeutic option for patients. The second thing that exercise does, especially resistance exercise, is build muscle mass. More metabolically active muscle tissue uses more blood glucose and facilitates better blood sugar control. So, patients with diabetes who increase lean muscle mass ultimately see benefits for 24 hour blood sugar control.
What types of exercise should patients be doing and for how long and how often?
This question is surprisingly difficult to answer, because the research is very controversial. As I already discussed, both aerobic exercise and resistance exercise are critical for patients with diabetes. That means 30-45 minutes a day of moderate intensity aerobic exercise such as walking, swimming and running. However, 2-3 days of resistance training a week is also really important. That might be 20 minutes of 10-12 different strength exercise that target large muscle masses in the core, upper and lower extremities. We also see some really positive benefits of what we call post-prandial exercise. That’s shorter, more frequent bouts of moderate exercise after a meal, such as 15-20 minutes of walking after each meal. At the end of the day, any exercise is better than no exercise for the patient with diabetes. In fact, simply just NOT sitting — getting up and walking around, standing, doing light intensity housework — can reduce hyperglycemia in diabetic patients. In other words, stay in motion!
Let’s talk about the benefits of healthy eating when you’re a diabetic. Are there certain foods that can have an impact?
We talk a lot about the glycemic index of foods, and trying to avoid foods with a high glycemic index. The glycemic index (GI) is a ranking of carbohydrates on a scale from 0 to 100 according to the extent to which they raise blood sugar levels after eating. Foods with a high GI are those which are rapidly digested and absorbed and result in marked fluctuations in blood sugar levels. Low-GI foods are much more slowly digested, often have more fiber, and are beneficial for weight control as well as blood sugar control. These include leafy greens, nuts and legumes, and whole-grain carbohydrates. A general rule of thumb is to avoid starch, processed foods: white rice, soda, processed meat and high-sugar foods. I personally advocate for the Mediterranean diet, which has benefits for both metabolic and cardiovascular disease. And, it’s enjoyable. You don’t meet native Italians who complain of their diet.