As competitive athletes, we’re often looking for a performance edge. This increase in performance can come in the form of the newest super-bike, carbon fiber wheels, more scientific training, or ...

First developed by the U.S. military, ketone supplements have caught on among runners and other endurance athletes. The promises are lofty: Pound back some ketones, and you’ll boost endurance by ...

When cells cannot access glucose as an energy source, the body turns to alternative fuels, such as fat. This process produces substances known as ketones, which can accumulate in blood and urine. In ...

My first visit to high altitude didn’t go well. I was at a training camp in the French Alps, and on one of our easy days my ...

Alex Hutchinson is a National Magazine Award-winning journalist and Outside’s Sweat Science columnist, covering the latest research on endurance and outdoor sports. There are, in the usual theoretical ...

Achieving ketosis—where your body burns fat for energy instead of carbs—is how people are losing weight on the keto diet, and it isn’t easy or instant. But can taking a supplement make the process ...

The stories of Asterix and his friend Obelix introduced us to a magic potion that comes in a small bottle and doesn’t taste good but dramatically increases strength and fitness. Sports nutrition ...