Athletes Who Follow a Ketogenic Diet Burn 2 Times More Fat
Is it really necessary to eat pasta the day before a marathon? A study published in Metabolism: Clinical and Experimental seems to go against the dogma of the “pasta party” diet, based on starches and other carbohydrates for endurance racers: athletes who follow a ketogenic diet low in carbohydrates, Have a much higher fat oxidation rate for equivalent performance.
A ketogenic diet consists of reducing carbohydrate intake, and greatly increasing fat, with the result that the body draws from its fat stores: fat is converted into ketones, which can be used by cells as a source of energy , Or even as an alternative to glucose. This diet is often accompanied by significant amounts of coconut oil. The effects of the ketogenic diet have been studied for years in the field of health, especially in certain diseases such as epilepsy, Alzheimer’s, cancer, Parkinson’s …
But recently, this diet has been adopted by a growing number of athletes, who therefore turn away from traditional pasta, rice and other carbohydrate overloads. It is therefore questionable whether this regime does not harm performance.
To find out, an American study involved 20 endurance riders aged 21 to 45 who performed well in races of 50 km or more or triathlon. Athletes had similar characteristics in terms of performance, age, training and maximum oxygen capacity (VO2 max). 10 of them followed a diet low in carbohydrates: 10% carbohydrates, 19% protein and 70% fat. The other 10 had a high carbohydrate diet: 59% carbohydrates, 14% protein and 25% fat.
Since it takes weeks for the body to adjust to a ketogenic diet, the average duration of the ketogenic diet was 20 weeks. The tests lasted two days. On the first day, the athletes ran on a mat to determine their maximum oxygen consumption and peak fat consumption. On the second day, the athletes ran for three hours on a mat at an intensity equal to 64% of their maximum oxygen capacity.
Results: The peak speed at which fats were burned was 1.5 g / min for riders with the low carb diet, or twice as much as the others (0.67 g / min). But, there was no difference in oxygen consumption, perceived fatigue or energy expenditure. The fat contribution during the exercise was 88% for low carb athletes and 56% for others. Muscle glycogen levels remained similar.
For Jeff Volek, lead author and professor at Ohio State University, “These low-carb athletes were spectacular fat burners. Their fat burning peak and the amount of burned fat running three hours on a treadmill were considerably higher than what athletes with a high carbohydrate diet were able to burn. “
This new study suggests that there is a large supply of fat available when carbohydrates are missing and that the amount of fat that humans can burn is underestimated. The ketogenic diet would thus offer an alternative to carbohydrates for endurance athletes. The ketogenic diet is a bit restrictive, but it can be tasty.
Our opinion: The idea that a high carbohydrate diet is necessary for good sports performance gained popularity in the 1960s when it was shown that the lack of glycogen in muscle was associated with Fatigue and that a high carbohydrate diet could maintain muscle glycogen level and performance. But, this pattern of thinking is changing rapidly. Fifteen years ago, low-carb diets such as Atkins appeared in athletes, and a dozen years ago, many athletes like Novak Djokovic have been able to adopt a gluten-free diet, Which translates into a decrease in carbohydrate intake. More recently, it is the paleo diet that has gained popularity among athletes, a diet that does not prohibit carbohydrates but it also leads to consuming less. The ketogenic diet takes a new step, since in this case carbohydrates of all origins are greatly reduced. Already experienced a decade ago by American Olympic teams, it is now penetrating. While the carbohydrate diet prevailed to date, it can be predicted that athletes will now have a wide range of dietary preparation options, ranging from carbohydrates to ketogenic, depending on the type of sport, The year (preparation or competition), the morphotype and of course the food tolerances. What give migraines to the dieticians-nutritionists who follow them! For example, that the feeding mode of the All Blacks, in rugby, had largely evolved in recent years, to accommodate more fat and less sugars.
Jeff S. Volek, Daniel J. Freidenreich, Catherine Saenz, Laura J. Kunces, Brent C. Creighton, Jenna M. Bartley, Patrick M. Davitt, Colleen X. Munoz, et al. Metabolic characteristics of keto-adapted ultra-endurance runners. Metabolism – Clinical and Experimental. Published online 2 November 2015.