Exercise suppresses eating by heating up a region of the brain called the hypothalamus, according to a study in mice.

Although it has long been clear that exercise can reduce appetite, the mechanism behind this effect has not been clear. Young-Hwan Jo and his colleagues at the Albert Einstein College of Medicine in New York City found that a class of brain cells in the hypothalamus that affect appetite also bear proteins called TRPV1-like receptors. These receptors respond to changes in temperature.

The team found that, in mice, a stint on the treadmill both raised the temperature of the hypothalamus and reduced eating. The same dual effect was seen after artificial stimulation of the neurons that express TRPV1-like receptors. Conversely, when the researchers turned down expression of the neurons’ Trpv1 gene, mice did not curb their food intake after exercise.