Here is a little tip given by researchers at the University of Granada (Spain) to boost the effectiveness of his workout. In their recent study, published in the Journal of the International Society of Sports Nutrition, scientists have shown that caffeine (about 3 mg / kg, or the equivalent of a strong coffee) ingested half an hour before aerobic physical exercise (activity which mainly relates to the heart rate and respiratory capacity) considerably increases the fat burning rate. They also found that if this physical exercise is done in the afternoon, the effects of caffeine are more marked than in the morning.
Concretely, the researchers wanted to determine whether caffeine, one of the ergogenic substances (capable of improving muscle work) the most consumed in the world for improve sports performance, actually increases the oxidation or “burning” of fat during exercise. Although its consumption in supplement form is very common, scientific evidence for its beneficial claims is scarce. “The recommendation of exercise on an empty stomach in the morning to increase fat oxidation is common. But it may lack a scientific basis, ”explains the main author of this research, Francisco José Amaro-Gahete.
An impact no matter the time of day, but …
Indeed, “we do not know if this increase is due to morning exercise or with the deprivation of food for a long period ”, adds the scientist. To do this, the team asked 15 men with an average age of 32 to perform a stress test four times over a 7-day period. Participants ingested 3 mg / kg of caffeine or placebo at 8 a.m. and 5 p.m. and each completed the tests under all four conditions in random order. The prerequisites for each stress test were the same for everyone: hours since the last meal, physical exercise or consumption of stimulating substances and fat oxidation during the year was calculated accordingly.
“The results of our study showed that the acute ingestion of caffeine 30 minutes before performing a testaerobic exercise was increasingmaximum oxidation of fats (lipids) during exercise regardless of the time of day “, adds Prof. Francisco J. Amaro, specifying that” the existence of a diurnal variation in fat oxidation during exercise has been confirmed, the values being higher in the afternoon than in the morning for equal hours of fasting ”. In addition, these results show that caffeine increases fat oxidation. during morning exercises in a manner similar to that observed without caffeine consumption in the afternoon.
In summary, the study suggests that the combination of acute caffeine intake and aerobic exercise performed at moderate intensity in the afternoon provides the optimal scenario for people looking to increase fat burning during exercise. Be careful, however, to respect the health recommendations in terms of caffeine consumption. In this regard, ANSES recommends prefer drinks naturally containing caffeine (tea, coffee) with artificially enriched drinks (energy drinks, etc.) and does not recommend coffee for people with certain pathologies (cardiovascular disorders, renal failure, severe liver disease, etc.).