Possibly you've heard the recent downer reports that exercise won't make us thin because it makes us hungry, particularly for junk victuals . Or could be, you've noticed firsthand that you eat a lot more on gym days than on days off. Either way, it raises the question: If working out only sets us up to blow our diet, what's the instant?
For starters, some research suggests exercise doesn't always cause hunger but can curb it. "Exercise may lower levels of ghrelin, a hormone that stimulates zeal in the short term, while raising levels of peptide YY, a hormone that suppresses appetite," says study originator David Stensel, Ph.D., reader in exercise metabolism at Loughborough University. That's only if the workout is intense (if you can chat, thoughts it), but the more intense it is, the longer the benefit seems to last. "It may be that your body needs to circulate more blood to prevent overheating," Stensel explains. Because eating would movement blood to flow to the stomach instead to aid digestion, your body dampens your appetite to prevent that.