Intermittent fasting is very fashionable at the moment. What is intermittent fasting? Who is it for? Is it compatible with sport? Here are the best answers.
According to Gilmore Health Intermittent fasting consists of giving up food for predetermined periods, days, or hours. The goal is often long-term weight loss. There are different types of fasting. For example, “giving up dinner”, i.e. skipping an evening meal. Other forms include fasting every other day, and the best-known form is 16:8, which means eating for 8 hours and then fasting for 16 hours.
In general, intermittent fasting has a lasting positive effect on health. Skipping dinner is said to lead to healthy weight loss and better sleep quality. This form of fasting is also said to improve insulin levels. Animal studies have shown that intermittent fasting reduces the risk of cardiovascular disease (e.g. diabetes). Unfortunately, very few studies have analyzed these effects in humans. The results are therefore less clear. However, existing studies show that intermittent fasting is a good alternative to conventional fasting in terms of weight loss, lean and fat mass, and glucose metabolism. It is therefore a suitable method for weight loss during exercise while preserving muscle mass. However, it is important to consider the nutrients and rations that the body receives during the non-fasting period. If you don’t eat a healthy and balanced diet or if you give your body too much energy, weight loss may be reduced or even stopped. On the other hand, this method of fasting can be detrimental to athletic performance.
As an athlete, if one adopts the “no dinner” method and still exercises in the late afternoon or early evening, recovery is clearly impaired. After the sports session, the body will be deficient in carbohydrates and protein, which also increases the risk of getting sick. If you still want to use this fasting method, it is better to train in the morning to provide your body with the nutrients it needs afterward. This is also very important for strength athletes, as protein intake allows them to optimize their training and improve muscle protein synthesis.
Things get more complicated when fasting is practiced for days on end. Nutrient intake is then too low or absent. It is, therefore, better to postpone exercise and train on non-fasting days. Otherwise, there is a risk that neither energy intake nor recovery capacity will be optimal, and the risk of injury or sickness will increase. In the most intense phases of training, this can also lead to over-exertion. Therefore, it is always good to think carefully about your goal and the phase during which you need to practice this fasting. Ideally, it should be done during periods of no training so that it does not affect performance and recovery. If it is to be done during training periods, the sessions should not be too intense or too long, as the body is deficient in key nutrients during this period and usually has a negative energy balance. If the energy balance remains negative for too long (e.g. several weeks) or falls too low, the risk of sickness and injury increases, and the quality of the workout is reduced. To avoid compromising long-term health, an individual plan should be put in place, and training, nutrition, and recovery should be coordinated.
Fasting is probably never the optimal solution for an athlete who wants to improve his performance. On the other hand, if you want to lose weight, this method may be suitable for you. However, the optimal timing of such an intervention and the coordination of training, recovery, and nutrition is extremely important. While this is perfectly feasible for amateur athletes who train 3 times a week, it becomes more complicated for athletes who train daily or even several times a day. In this case, weight loss can be achieved through other dietary modifications, without limiting athletic performance or recovery and without skipping meals. Therefore, it is advisable to consult a sports nutritionist to determine the right time and measures to lose weight.
Johns Hopkins: Intermittent Fasting Could Help You Live Longer. Gilmore Health News
What is intermittent fasting? Does it have health benefits? Mayo Clinic
The benefits of intermittent fasting the right way. BBC