physiology

Endurance-science experts explain Eliud Kipchoge's incredible marathon dominance.

Gut problems in runners have myriad sources — from stress to heat, caffeine to sleep deprivation — and all of them can sabotage your performance.

If your legs fall asleep, lose control, or tingle when you run, you’re not alone. Here are some potential causes and solutions.

A new science paper explores the subject at great depth, and concludes that it's possible, but not likely.

The performance benefits of the world’s favorite chemical could be washed out if it causes trouble in your gut.

Loads of factors within and outside the body contribute to nausea during ultramarathons, but there are some ways to mitigate it.

Your DNA has a say in your caffeine buzz, but it’s still not clear how genes affect gut sensitivity to caffeine.

It’s bad enough sweating it out in scorching heat. Then comes stomach pain or irritated bowels.

One Canadian researcher is trying to find the answer to that question.