Hungry for More: How to Manage Post-Workout Cravings

The Food-Exercise Equation

Two days ago I logged my usual 12 laps around the local track. I finished hungry but happy. When I popped over there today, I found the track gone, razed by bulldozers now sitting atop a huge pile of mud. How was I supposed to lose weight if I had no place to exercise?

Actually, skipping my workout might not be a bad thing, according to a hotly contested idea circulating among researchers and making headlines in publications such as The New York Times and Time magazine. Exercise, ironically, is being singled out by some as a deterrent to weight-loss efforts. Say what?

"There's this hunger issue," says Kendrin Sonneville, RD, a researcher at the Harvard School of Public Health. Her study about how kids who exercised the most ate back all the calories they burned off, and then some, was featured in a Time cover story, "Why Exercise Won't Make You Thin," last fall. "After the article came out, my sister called me and asked, 'So, is exercise a waste of time?' " Sonneville's reply: "No, but it's not a panacea for weight-loss either, because it does increase your appetite. The food-exercise equation is imbalanced. It may take an hour to burn 500 calories but only five minutes to eat them back."

And that's exactly what your body wants you to do. "In the short term, during or right after a workout, exercise may suppress hunger," says Barry Braun, PhD, professor of kinesi­ology and director of the Energy Metabolism Laboratory at the University of Massachusetts in Amherst. "But later that day, your hunger hormones can surge, making you want to eat. At the same time, your body's satiety hormones -- the ones that signal that you're full -- may decrease." The really unfair part, Braun notes, is that the desire to eat more after exercising hits women harder than men. "When we look at blood samples of people starting an exercise program, there is a subtle change in men's hormone levels, but for women, exercise really elevates the hormone that increases appetite," he says. "The widely accepted theory is that women's bodies are hardwired to hold onto energy for reproduction purposes." So when your body senses that you're burning fuel from exercise, it wants to be sure you replace it pronto.

All of which means that for women who love fitness and want to be toned as well as trim, shedding pounds poses a unique challenge. But the payoff is well worth it: "What all the latest news stories missed is the role exercise plays in keeping the pounds off in the long run," says Timothy Church, MD, PhD, a professor at the Pennington Biomedical Research Center in Baton Rouge, Louisiana, who has done extensive research on the factors that influence successful weight loss. "It's a fact that the only people who keep off the weight they've lost are the ones who are physically active." Those who use dieting alone to drop pounds usually find themselves right back where they started or even heavier, studies show. Beyond slimming you down, exercise offers other major benefits: It blasts dangerous belly fat; reduces your risk of high cholesterol, heart disease, and diabetes; and makes you happy -- each of which can help you live longer.