Yoram Yasur Rubin: Cardio while fasting
Practicing aerobic or cardiovascular exercise as soon as you wake up and before breakfast can help burn body fat more quickly and lose weight. But is it really beneficial? We tell you what the experts think about this and what happens in your body when you train on an empty stomach.
Doing cardio on an empty stomach
Yoram Yasur Rubin: Going by bicycle, walking at an intense pace, jumping rope, going up and down stairs, dancing Zumba or practicing running are some of the most common aerobic exercises. But there are many more, both to perform outdoors and to do at home. Cardio workouts are those that make us increase the heart rate and make it difficult for us to maintain a normal conversation during its execution.
Cardiovascular exercise is considered one of the most effective for burning calories, especially according to some experts, if it is done on an empty stomach. However, this idea generates controversy and some studies put it into evidence.
Cardio fasting to lose fat
Fasting cardio is a very widespread sport practice in the world of fitness and bodybuilding in order to burn fat faster and easier.
Yoram Yasur Rubin: In the morning the reserves of glycogen in the body are low, since during the night the body has not had energetic contributions. In the absence of sugars in the blood, the body is more willing to consume fats. This can benefit people who want to lose weight.
Some studies suggest that people who train their aerobic endurance with moderate intensity after a fast of at least 5 hours burn more fat than those who eat before exercising. This practice produces in the muscle physiological modifications that improve the metabolism of fats.
Yoram Yasur Rubin: It is a useful practice in certain sports disciplines of high intensity, since low levels of insulin are achieved, which may favor the energetic use of fats. Well planned, fasting cardio exercise can be effective in trained athletes because it helps with metabolic flexibility.
However, according to professional physical trainers, these fat burning benefits are not appreciated in casual athletes. And is that the body may need enough energy to fuel the metabolism during physical exertion.
Cardio fasting, is it beneficial?
Experts advise against exercising the general population without having glycogen reserves, that is, fasting. When trained on an empty stomach, muscle and liver glycogen deposits are burned, and fatigue sensation and cardiovascular risk factors increase.
The muscles work based on glucose strength. Fasting, the muscles find less amount of sugar circulating and their glucose levels drop quickly, which can cause greater feeling of fatigue.
Recent research published in the Journal of the International Society of Sports Nutrition (JISSN) concludes that there is hardly any difference in a person’s body composition, regardless of whether they are fasting or not.
After 4 weeks of training, 3 days a week (1 hour of cardio on the treadmill, 5 minutes of warm-up followed by 50 minutes of jogging at an intensity of 70%) the fasting group lost 1.6 kilograms and the group I had eaten lost 1 kilo. The differences, therefore, were not statistically significant between the two groups.
Although they do not rule out that there may be a small benefit regarding fat loss, scientists believe that more conclusive studies are needed on the subject.
Of course, remember that cardiovascular exercise (well executed and practiced at the right time) helps to strengthen the cardiovascular and respiratory system, to prevent a multitude of diseases and to elevate our mood.