The Blog



The daily sports practice is one of the activities that cannot be missed if we want to follow healthy habits. And, in the case of diabetics, this factor takes on special relevance.

Keeping fit and active every day (at least 30 minutes of exercise per day), will facilitate the control of blood sugar, as well as helping our body to process hydrates without resorting to so much insulin.

Today we will address all the questions you may have about diabetes and exercise for diabetics. In this way you could take advantage of the maximum benefits of sports and take care of your health. Remember to protect your feet with special shoes, here at Happy Feet Pedorthics you can get personalised shoes at an affordable price.

Many of the people who have better control of their diabetes are those who perform physical exercise on a regular basis. Everyone should perform some type of physical activity, since the effects not only improve glycaemic control but have an effect on other functions of our body:

  • Exercise increases caloric expenditure and helps maintain the right weight.
  • It helps maintain cholesterol and triglyceride levels in the normal range.
  • It helps keep blood pressure within normal limits.
  • Improves the vascularization of the heart.
  • Improves the feeling of well-being.
  • It helps maintain a good vascularization of the feet.
  • It can favour social integration.

For all these reasons, the international recommendations are that at least 30 minutes of physical exercise be performed daily.

Effects of exercise on the blood glucose level

  • Increases the absorption of insulin from the injection site into the blood.
  • It decreases the insulin requirements since it improves the sensitivity to it.
  • The effect that occurs during exercise is that the body tends to use more glucose, the result being a decrease in sugar levels during physical activity.
  • There is also a prolonged period that can last up to 24 hours post-exercise of increased insulin sensitivity in which blood glucose will tend to be lower. This is due to the fact that the glycogen reserve of the liver has been used during the exercise. This reserve tends to “refill” after exercise, hence the blood glucose decreases.

Advice when doing physical exercise

The most advisable types of exercise are the aerobic exercises (cycling, jogging, soccer…) because they favour the blood circulation and nutrition of all the cells. For the exercise to be more effective it is important that it be daily, of similar intensity and duration, and fun.

When NOT to do physical exercise?

If there is acetone in blood or urine, you cannot exercise because the ketone bodies would increase more.

How often should physical exercise be done?

At least 30 minutes every day.

What precautions should be taken when exercising?

It is very important to assess the glycemia before exercising and consider the type of exercise that is going to be performed, the amount of insulin that has been administered and the previous feeding.

Pre-exercise insulin should not be given in an area of the body that is going to be very active during exercise (for example, not piercing your legs if you are going to ride a bicycle).

Prevention of hypoglycaemia associated with physical exercise

There are two possibilities of having hypoglycaemia associated with physical exercise. The first one is having a “low” during the physical exercise. The second possibility is to have a “delayed hypoglycaemia”. Delayed hypoglycaemia can occur 4 to 24 hours after finishing physical activity.

The recommendations to avoid hypoglycaemia associated with exercise are the following:

  • Plan ahead so you can eat and administer the fast-acting insulin 1 to 2 hours before exercising. In this way, you can reduce the previous dose of insulin and inject it in a place that will not be very active during exercise.
  • Get blood glucose checks before, during and after exercise. The appropriate values to begin physical exercise are between 130 and 250 mg / dl. If the blood glucose is below 130 mg / dl, you should eat something before you start. If the blood glucose is greater than 250 mg / dl, a determination of ketone bodies should be made, because if these are positive, exercise should not be done.
  • If the exercise is prolonged (> 30 or 45 minutes) you should eat something during the exercise. For every 30 minutes of intense exercise you will need 10 to 15 extra grams of carbohydrates.
  • Decrease insulin dose after exercise (both the fast-acting and slow-acting insulin doses). In some cases, the decrease can be up to 50% of the total dose.

If increased physical activity is combined with alcohol consumption, the problems will be greater because alcohol blocks the body’s ability to respond to hypoglycaemia, which can cause severe hypoglycaemia and seizures or unconsciousness if it is not decreases the insulin dose.

These recommendations are general. The most important thing is to base ourselves on our own experience and on the advice of our diabetologist.

Hyperglycaemia associated with exercise

Exercise is probably one of the most difficult parameters to control in diabetes. Although its effect, in general, is a decrease in blood glucose, there are times when the effect may be the opposite and hyperglycaemia may occur. The hyperglycaemia associated with physical exercise is due to the release of catecholamines (stress hormones) that increase blood glucose. The effect of these hormones is short since they usually last from 1 hour to 1 hour and a half. Therefore, immediate post-exercise hyperglycaemia should not be corrected.

Another situation is that the blood glucose increases during exercise due to lack of insulin. The glucose level will increase if you exercise and insulin levels in the body are low. Muscle cells need more energy, they get “burning” glucose, but because there is not enough insulin, glucose cannot enter the cells, and therefore the body acts as if there is not enough sugar in the blood and stimulates the liver to get more sugar out of your reserve. This causes blood glucose levels to increase more. The way to correct this problem would be by injecting insulin.

Here at Happy Feet Pedorthics we can help you find the best option for you, we’ll assist you in the selection of shoes for your daily routine.