How you know you're exercise is working

From Women's Health:

Sign No. 7 You don't run from the gym to the fridge.
If you're hungry after what was supposed to be a high-intensity workout, you took it too easy. "Intense exercise tends to curb appetite," says Leslie Bonci, R.D., director of sports medicine nutrition at the University of Pittsburgh Medical Center. The workout-induced appetite lull occurs because the area of the brain that regulates hunger — aka the appestat — decreases when you're hot, zapping food cravings. Exercise also stimulates the secretion of a hormone that suppresses hunger. Although you shouldn't feel hungry for 1 to 2 hours after a butt-kicking workout, you should try to eat a snack, such as a handful of trail mix, within 20 minutes to speed recovery and prevent yourself from diving headfirst into a bag of Cool Ranch Doritos when the effect wears off.