Regular exercise makes a difference to diabetics. Here’s how and why.
Mr. C., a 50-year-old bank employee, was diagnosed with diabetes and advised to exercise regularly, in addition to diet and medication. He wants to know the benefits of regular exercise.
Diabetes develops when the body's cells are unable to utilise the glucose present in the blood, either due to a lack of insulin or its inability to work properly (insulin resistance). This leads to accumulation of glucose in the blood, which can cause severe complications. Exercise helps sensitise the body's cells to the effects of insulin and also leads to improvement in muscle mass. Muscles are one of the major sites of glucose utilisation. A regular exercise regimen also helps a person lose weight, which in turn improves insulin sensitivity. Exercise also has wide-ranging effects including improving lipid profile, reducing blood pressure and stress levels and improving quality of life.
What sort of exercise should he do?
There are no restrictions on the type of exercise, except in a few situations (see below). It is important to choose an activity that is fun and that one can motivate oneself to do every day, even after the novelty value has worn off! Some examples include brisk walking, jogging, cycling, swimming and sports like tennis, squash and badminton. All one needs are a pair of well-fitting shoes (do not compromise on these), padded soft socks and a steady supply of willpower.
Patients with diabetes are recommended a minimum of 150 minutes of moderate intensity exercise a week i.e. at least 30 minutes a day for five days a week. Remember, this is bare minimum; if attempting to lose weight, one should aim for at least double of this.
Is there a difference in exercise if one has Type 1 or Type 2 diabetes?
Type 2 diabetes (which Mr. C has) is the most common form. This is characterised by high blood sugar levels as a consequence of defective action of insulin, with varying degrees of deficient insulin secretion. While it is not possible to increase insulin secretion significantly by means of physical activity, the biological effects of insulin can be enhanced by increasing exercise levels.
In type 1 diabetes, the primary problem is absolute deficiency of insulin. Although the benefits of exercise in actually controlling blood sugars in type 1 diabetes is less clear, there is no doubt that the other benefits of exercise hold good in these individuals.
Mr. C is now ready to start. He decides to start by participating in a marathon. His doctor, however, is not enthusiastic!
There are very few restrictions in initiating an exercise programme, especially if there are no complications or if the diabetes is of recent onset. However, a few precautions are necessary. The motto should be to “start low and go slow”. There is no point in running a marathon on Day One if one is going to be bedridden for the next two weeks!
Exercise should be avoided if the blood sugar levels are very high (>250 mg/dl); as sugar levels may temporarily rise even higher, particularly in type 1 diabetes. Also, individuals with type 1 diabetes should not exercise if they have ketones in their urine or if they have low sugar (hypoglycaemia) symptoms. It is better to avoid exercising if one is otherwise unwell.
While individuals with eye complications can generally perform all types of exercise, strenuous activities like straining, lifting heavy weights and jarring movements should be avoided, as this may lead to bleeding into the eye. Individuals with severe nerve disease (neuropathy) should avoid activities that can injure the feet, as they may be unaware of such injuries.
Individuals with a family history of heart disease, long duration of diabetes (more than 10 years) or other risk factors for heart disease (like older age, history of smoking, high blood pressure or high cholesterol) should undergo a thorough cardiac evaluation before starting exercise.
Mr. C started with a brisk 45-minute walk a day. However after three days, he reports that he feels more tired than usual and has some pain in his thighs.
A few aches and pains are common when a sedentary person starts exercising. These settle once the body gets used to the new routine. If one is unable to talk normally or feels short of breath while exercising, it probably means the exercise is too vigorous. Scale down the intensity a little. Also stretch muscles before and after working out, to minimise risk of injury.
Mr. C has been regularly exercising for the last three months. His aches and pains have disappeared. But he has not lost any weight. Is he doing something wrong?
Weight loss depends on the calorie intake as well as the calorie expenditure. Also remember weight loss is not the be-all and end-all of exercise. When one exercises regularly, one loses fat and builds muscle. It is more important that to lose inches off the waist even if one does not lose kilos. Rely on the inch tape rather than the bathroom scale. Finally, remember one has to spend 8000 calories to reduce one kg in weight. Obviously, as one expends more calories and also watches the calorie intake, weight loss will occur faster.
Mr. C is temporarily posted to a remote village for six months. He spends a lot of time commuting. Will he be able to continue exercising?
Finding an hour to exercise might look like too much. However, there are ways in which physical activity can be incorporated into the daily routine.
One year later, Mr. C's doctor has cut his medication since his blood sugars are under control. But Mr C says, “I want to get back to as normal as possible. I know I can get there with my exercise regime. Starting regular exercise was the best thing I ever did in my life!”
No time to exercise?
Here's how you can continue to work out.
Choose a longer way while walking
Use the staircase instead of the lift
Within the office, walk to your colleague's seat rather than using the intercom
Park the vehicle farther away from the destination and walk the rest of the distance
Get down from the bus at an earlier stop and walk the rest of the way
The authors are Chennai-based diabetologists.