Everyone can spot a runner. They're long, lean and look like they haven't had a square meal in days.
A new study from the American Physiological Society suggests an explanation: aerobic exercise, like running, suppresses hunger.
The researchers put eleven healthy, male college students through an exercise wringer. The students ran on treadmills and lifted weights during three eight-hour sessions.
Levels of a hormone that causes hunger dropped during both types of workouts. But only the aerobic exercise also released a hormone that suppressed appetite.
The researchers think a possible reason is because more energy is used during aerobic exercise compared to the stop and go nature of weight lifting.