nutrition

Rob Rhinehart lived on his liquid invention for 30 days straight, and the feat propelled him to internet fame and fortune.

Through years of training as an ultra runner, Timothy Olson has taught his body to become "fat-adapted," using fat from animals and plants to fuel him through feats that seems superhuman.

We follow the UK-based international pro bodybuilder Rene Campbell, who eats the same high-calorie meal every three hours, seven days a week.