There really is a runner’s high

If you run, you’ve probably experienced a “high” at some point — a euphoric feeling that just makes you want to keep on going. Now science says it’s not just in the mind, and has pointed to a surprising reason for it: nature may be encouraging you to look for food by making the effort seem less strenuous.

Scientists at the University of Montréal have found that the runner’s high may be related to the levels of the hormone leptin in the blood. Leptin is known as the satiety hormone, which tells the body to shut down hunger pangs when there’s enough fuel on board. The researchers found that when you’re moving and using energy, leptin levels eventually drop to a point where a signal is sent to the brain to increase stamina and make running seem rewarding. This may be nature’s way of facilitating “the pursuit of food,” said a researcher.