Keto-Adaptation And Athletic Performance

Keto-adaptation refers to the adaptation the body undergoes as one's metabolism shifts from one which utilizes sugar (glucose) as the primary source of energy, to one which utilizes primarily fat instead. The common belief that persists is that the human body needs carbohydrate to engage in high intensity training. However, this flawed but popular belief stems from only short-term studies which did not take into account the changes the body undergoes over a period of weeks and even months when carbohydrates are restricted and the body begins to adapt to using fat as its main energy source. It often takes up to two weeks for a person to fully adapt to being in a state of ketosis, and probably a bit longer to really fine tune that adaptation to fuel high intensity workouts. During this window of adaptation, performance will undoubtedly suffer and should be therefore limited to only low intensity or none at all.

It turns out that fat may be the new athletic fuel as more and more athletes are becoming aware of the benefits of high fat, low carbohydrate diets in athletic performance, including strength training and endurance sports. The fact is that a body which runs on sugar has only a limited storage tank of energy. Once glycogen stores are depleted, a person hits the wall unless they replenish that spent glycogen. When a person adapts to using fat as their primary energy source, they have an unlimited supply of fuel, making fats the ideal fuel for people engaged in things like long-distance biking and running. People who follow low carb or ketogenic diets are always in fat burning mode, so once they have used up their energy in dietary fat, they seamlessly begin to burn the body's fat stores. Even the leanest of people have tens of thousands of calories stored within their bodies to be used for energy.

A person who is keto-adapated is also going to be preserving muscle when in a calorie deficit or fasted state, whereas high carb diets often result in the catabolization of muscle as opposed to fat, since the body is not conditioned to burn fat and is looking for sugar. Through the process of gluconeogensis, a body conditioned to use carbs for energy turns to the breakdown of muscle tissue to elevate blood sugar levels. This also results in the creation and storage of fat through elevated insulin levels coupled with a spike in cortisol levels.

Dr. Peter Attia elucidates this topic well in the video below. Highly recommended for anyone who's interested in low carbohydrate performance.

http://youtu.be/hB7aGnfLB-8

Also this video presentation by Dr. Stephen Phinney, perhaps the world's leading expert on low carbohydrate diets and performance, as well as one of the two authors of the excellent book The Art and Science of Low Carbohydrate Performance.

http://youtu.be/GkQYZ6FbsmI