Exercise and how it relates to type I and type II diabetes.
Regular physical exercise has a beneficial impact on body composition, cardiovascular integrity, insulin sensitivity, and quality of life. All crucial points to controlling diabetes. Key guidelines for regular exercise in adults are: Adults should move more and sit less, some activity is better than none and every bit counts. For substantial health benefits, adults should do at least 150 to 300 minutes (2.5 - 5 hours) a week of moderate-intensity exercise OR 75 to 150 minutes (1.25 - 2.5 hours) a week of vigorous-intensity aerobic exercise OR a combination of the two. Adults should also do muscle strengthening activities on two or more days a week at a moderate or greater intensity involving all major muscle groups (6).
The prevalence of diabetes mellitus is rapidly increasing worldwide. The number of people with diabetes, between the ages of 20-79 years of age, will increase over the next 20 years from 415 million in 2015 to 642 million by 2040 (5). Majority of people have type II diabetes, but an important minority have type I diabetes. Health dangers for people with diabetes includes: Risk for stroke, heart attack, hypertension, kidney failure, blindness, lower-limb amputations, gum disease, hearing loss, nonalcoholic fatty liver disease, elevated LDL cholesterol (bad cholesterol), and mild to severe forms of nerve disease (4).
Type I diabetes is not a childhood disease, it occurs at every age, in people of every race, of every shape and size and accounts for only 5-10% of the cases (1). Type I diabetes is an autoimmune disease where the body's defense mechanism mistakenly attacks its own pancreatic cells that produce insulin, leaving the body depleted. Insulin is the hormone that allows glucose to move from the bloodstream into the cells of the body. When carbohydrates are consumed they are broken down into glucose and circulate in the bloodstream to be utilized for energy. When glucose is not being used for immediate energy it gets stored in the liver, muscles, or when in excess, as adipose tissue. Without insulin injections or exercise, there is no way for the body to regulate glucose in the bloodstream within normal levels. Exercise for people with type I diabetes, it’s very important to balance your insulin doses with the food you eat and the activity that you do, even if you are just doing house or yard work. Planning ahead and knowing your body’s typical blood glucose response to exercise can help you keep your blood glucose from going too low or too high. Self glucose monitoring is a good habit to practice (1).
Type II diabetes, formerly known as non-insulin-dependent and / or adult-onset diabetes, accounts for about 90% of diabetes cases and can happen at any age (5). Type II diabetes is when your pancreas is fully able to make insulin but your body does not use it properly. When there is an excess amount of glucose in the bloodstream, the body’s cells become unable to take up the extra glucose. The pancreas is still doing its job by releasing insulin but there becomes an abundance of it, over time the pancreas cannot keep up with production, the insulin becomes less sensitive and does not respond; this is called insulin resistance.
During exercise, the most important factors influencing fuel use are intensity and duration. Muscle glycogen provides plenty of fuel for working muscles, but as those stores are depleted with increased intensity, muscles increase their uptake and utilization of circulating blood glucose and free fatty acids (3). Colberg and colleagues note that the uptake of blood glucose on working muscles remains elevated for several hours, a very noteworthy benefit of exercise. Recent research has shown that resistance exercise is as important as, and perhaps even more important than, aerobic training in diabetes management. An increase in muscle mass resulting from resistance training can contribute profoundly to glucose uptake. However, a combination of aerobic exercise and resistance training is more effective for blood glucose control than either type of exercise alone. Physical activity of any intensity will provide acute effects by enhancing blood glucose uptake for glycogen synthesis and by stimulating fat oxidation (breakdown) in muscle. Colberg and colleagues add that current research suggests that longer-duration and more-intense training sessions elicit the best results for blood glucose reductions (3).
Regardless of the type of diabetes you have, regular physical activity is important for your overall health and wellness. Exercise improves your cardiovascular and respiratory function, decreases blood pressure, increases HDL (good) cholesterol, decreases triglycerides, reduces body fat (especially intra-abdominal fat), reduces insulin needs, decreases risk of morbidity and mortality, decreases in anxiety and depression, increase feelings of well-being, enhance cognitive function and performance, and an effective therapy for for many chronic diseases (2).
Contact one of our personal trainers if you're looking to learn how to exercise with diabetes! Be sure to share this article with anyone you know who is a diabetic - they may just learn what they need to succeed! Thank you for reading!
Quinn Butler, M.S., CPT
(1) ADA. 2014a. Standards o f medical care in diabetes—2014. Diabetes Care, 37 (Suppl. 1), S14-S80.
(2) Benefits and Risks Associated with Physical Activity. American College of Sports Medicine.
(3) Colberg, S.R., et al. 2010. Exercise and type 2 diabetes. Diabetes Care, 33 (12), el47-67.
(4) IDEA Fitness Journal. Diabetes & Exercise: What Every Fitness Professional Should Know, Vol. 11, Issue 8, p.40-47; 2014.
(5) International Diabetes Federation (IDF), 2015, Diabetes Atlas, Seventh Edition.
(6) U.S. Department of Health and Human Services. Physical Activity Guidelines for Americans, 2nd edition. Washington, DC: U.S. Department of Health and Human Services; 2018.