How to Exercise With Insulin Resistance?

Insulin resistance – what does it involve?

Insulin resistance is a condition in which our tissues are less sensitive to insulin, the hormone responsible for regulating blood glucose levels. This is the shortest definition of this phenomenon, but – to understand it better – let us trace its mechanism.

Glucose is our body’s fuel – it is a source of readily available energy, which we supply with food, store in our muscles and liver in the form of glycogen, and burn in tissues. Insulin is a hormone produced in the pancreas that occurs at every stage of carbohydrate metabolism. During the transport of blood glucose into the cell, insulin acts as a “door key” for glucose absorption. Figuratively speaking – the problem begins when the “door” does not want to open.

There are different types and sources of insulin resistance, but the most common is post-receptor insulin resistance. It is a condition in which cellular “doors” in the muscles and liver are blocked, despite the fact that the insulin “key” fits into them. As a result, glucose stays in the bloodstream, forcing the body to produce more insulin. When its excess is finally metabolised, it is deposited as spare material in adipose tissue.

The road to insulin resistance begins with excessively calorific meals and poor eating habits. This, combined with a lack of physical activity, provides a great environment for the development of excess body fat and obesity. In turn, this causes the “door” to our muscles and liver to be blocked (we have less insulin sensitivity), so it takes more insulin to get rid of excess glucose from the bloodstream, which again translates into an expansion of body fat... This is how the “vicious cycle of insulin resistance” is created, the consequence of which can be such serious diseases as type 2 diabetes.

What kind of training is best for people with insulin resistance?

Once again, the saying that any activity is better than none applies here. The rationale for this is simple – by burning glycogen stored in the muscles and expending a certain amount of energy, we “make room” for the next portion of glucose to be stored as glycogen. Our tissues also become more sensitive to insulin, and the body uses it more efficiently to create glucose transport proteins.

Moderate-intensity aerobic training helps burn body fat and increases tissue insulin sensitivity by up to 50%. This effect lasts up to 72 hours after the session! The basic prerequisite for the success of such training in counteracting insulin resistance is regularity – systematic aerobic exercise of any kind (running, cycling, Nordic and power walking, swimming, dancing, etc.) works well here regardless of body weight and other metabolic indicators.

Resistance training in any form also proves helpful. Exercising on machines, with free weights or your own body weight increases muscle mass – and therefore demand for glycogen. Consequently, the insulin sensitivity of tissues increases. Resistance training also supports the production of glucose transporters. The most helpful in counteracting insulin resistance will be general training, affecting many muscle groups.

High-intensity training, on the other hand, can be problematic. Studies show that interval training (HIIT) is sometimes more effective than aerobic training, especially in people with low levels of insulin resistance. Unfortunately, beginners struggling with more severe obesity or cardiovascular diseases will not be able to benefit from this form of activity. Long, intense workout sessions are not advised for people with insulin resistance either. Excessive exercise causes the release of hormones antagonistic to insulin, such as cortisol. Post-exercise inflammation and lower glucose tolerance are also not conducive to counteracting insulin resistance. To sum up, if you exercise intensively, it should be short. Otherwise, aerobic training is better.

Here are two practical considerations that are particularly relevant for people with insulin resistance:

• Remember about recovery – exercise and stress increase cortisol levels, which act antagonistically to insulin. Thus, rest or daily NEAT activities are definitely a better choice than additional training sessions.
• Do not exercise on an empty stomach – in such a situation, people with insulin resistance are more likely to experience a state of hypoglycaemia, i.e. blood glucose levels that are too low. This can cause weakness, nausea, muscle tremors and even unconsciousness.

Diet in insulin resistance – what helps and what doesn’t?

For insulin resistance, it is worth paying attention to the glycaemic index (GI) of food products in the first place. This indicator determines at what rate the carbohydrates in the food will be absorbed into the bloodstream. The higher – the greater the release of glucose into the blood after a meal. Does this mean that the lower the GI, the better? Not necessarily. This is because the glycaemic index does not take into account the amount of food we eat, and therefore the number of calories and the total glycaemic load we provide with a meal. In other words, people with insulin resistance can afford to eat small amounts of high-GI foods. In contrast, large quantities of low-GI foods will not necessarily be a good choice.

In most cases, therefore, the key element of the diet for people with insulin resistance will not be low-GI foods, but an energy deficit. The goal is to reduce body fat, but this does not necessarily mean drastically reducing carbohydrate intake. Of greater importance is their type, source of origin and the habits that accompany their consumption. The sugars present in, for example, vegetables, fruit, cereals or pasta are fine and often feature in all kinds of weight loss diets. To “overload” the body with glucose from them, we would have to absorb them in huge quantities. And yet, this is unlikely to happen as often as with “convenience” foods – colourful, tasty, encouraging you to reach for another, and then another, serving.

One of the most important rules for the effectiveness of diet in insulin resistance is that the best diet is the one you are able to follow. One that not only provides you with an adequate calorie deficit, but also does not require huge and complicated purchases, long hours spent cooking and many other sacrifices. The simplest solution is to consult a diet specialist, with whom you will jointly establish an accurate plan tailored to individual parameters of body composition, your preferences and lifestyle. There are no miracle solutions – it is “grassroots work” that matters.

Bet on regularity

Countering insulin resistance is not about rigorous sacrifices. It is definitely more important to do what is realistic. When it comes to workout, it should be one that is easily accessible to you, you are able to do it regularly and enjoy it. In turn, when it comes to diet, it should be one that sets specific, measurable and achievable goals and makes it relatively easy to achieve them.

The key to success is not a one-time effort, but regularity, which allows to develop good and healthy habits. You can arrive at it on your own – although this often involves trial and error. You can also take advantage of a customised plan developed with a dietician and trainer – and that is what we recommend.

_References:

1.  _{Wilcox G., Insulin and Insulin Resistance, Clinical Biochemist Reviews, 2005.}
2. _{Mann S., Beedie C., Balducci S. i inni, Changes in insulin sensitivity in response to different modalities of exercise: a review of the evidence, Diabetes / Metabolism Research and Reviews, 2014.}
3. _{Poehlman E. T., Dvorak R. V., DeNino W. F. i inni, Effects of Resistance Training and Endurance Training on Insulin Sensitivity in Nonobese, Young Women: A Controlled Randomized Trial, The Journal of Clinical Endocrinology & Metabolism, 2000.}
4. _{Niemann M. J., Tucker L. A., Bailey B. W., Davidson L. E., Strength Training and Insulin Resistance: The Mediating Role of Body Composition, Journal of Diabetes, Research 2020.}
5. _{Keshel T. E., Coker R. H., Exercise Training and Insulin Resistance: A Current Review, Journal of Obesity and Weight Loss Therapy, 2015.}
6. _{Marson E. C., Sudatti Delevatti R., Netto N. i inni, Effects of aerobic, resistance, and combined exercise training on insulin resistance markers in overweight or obese children and adolescents: A systematic review and meta-analysis, Preventive Medicine, 2016.}
7. _{Conde S. V., Martins F. O., Impact of Diet Composition on Insulin Resistance, Nutrients, 2022.}
8. _{Gołąbek K. D., Regulska-Ilow B., Dietary support in insulin resistance: An overview of current scientific reports, Advances in Clinical and Experimental Medicine (Wroclaw Medical University), 2019.}
9. _{https://insulinoopornosc.com/ - strona Fundacji Insulinooporność, dostęp: 7.10.2024.}