Diabetes and Exercise
Diabetes is an epidemic that is affecting a large portion of the North American population in particular. There are two distinct types of diabetes that are most frequently seen, one that is genetic in nature and one that is related to lifestyle. Type 1 diabetes is caused by the body’s immune system destroying cells that produce insulin (insulin is responsible for maintaining blood sugar levels). Conversely, people with Type 2 diabetes are able to produce insulin but the cells are unable to efficiently utilize it; an issue called insulin resistance. One of the main causes of Type 2 diabetes is obesity, especially if you have a large portion of body fat around the midsection.
Type 1 Diabetes
The biggest issues when you have Type 1 diabetes is that you can easily fluctuate between hyperglycemia (high blood sugar levels) to hypoglycemia (low blood sugar levels). Normal levels for blood sugars are approximately somewhere between 3.3-7.8 mmol/L. Both hyper and hypoglycemia can happen before, during and after exercise so we must be careful when we exercise to watch for sign and symptoms:
- Racing pulse
- Cold sweat
- Pale face
- Feeling incredibly hungry
- Shivering, feeling weak in the knees
- Feeling restless, nervous or anxious
- Difficulty concentrating, confusion
- Extreme thirst, drinking a lot and then urinating frequently as a result
- Unintentionally losing a lot of weight within a few weeks
- Noticeable loss of energy with muscle weakness, tiredness and a strongly impaired
- general condition
- Nausea and stomach pain
- Trouble seeing
- Poor concentration
- Frequent infections (cystitis, thrush)
- Confusion and drowsiness, or even coma
If someone comes in to exercise with low blood sugar levels they should be getting a fast acting carbohydrate into their system (sports drink or glucose tab). Wait 15-20 minutes and check their sugars again. Conversely, if someone comes in with high blood glucose get them to take insulin and try to lower their levels.
Type 2 Diabetes
People with Type 2 diabetes are less likely to have issues with hypoglycemia during or after exercise. Monitoring blood glucose levels for this population is also important but it is most important to exercise since exercise and nutrition are the best ways to promote weight loss (a common occurrence in T2D). Note: if your ketone level is higher than 240mg/dl then you must check your urine for ketones before exercising.
Benefits of Exercise
With moderate to intense physical activity people with diabetes have lower morbidity and mortality rates. Diabetics may also see an increased cardiorespiratory fitness, increased vigour, improved glycemic control, lower A1C levels, decreased insulin resistance, improved lipid profile, blood pressure reduction and maintenance of weight loss.
Recommendations (Canadian Journal of Diabetes, 2013)
People with diabetes should accumulate a minimum of 150 minutes of moderate- to vigorous- intensity aerobic exercise each week, spread over at least 3 days of the week, with no more than 2 consecutive days without exercise. People with diabetes (including elderly people) should perform resistance exercise at least twice a week and preferably 3 times per week in addition to aerobic exercise.