The Truth: Studies have shown that exercise actually suppresses food intake.
After a long, hard workout, are you one of those gym rats who immediately grabs a meal or gulps down a sugary, colorful sports drink to “re-fuel”? The truth is, this behavior stems more from habit than from actual, legitimate hunger. In fact, studies show that exercise suppresses your hunger!
Your hunger-stimulating hormones decrease when you exercise. Physical activity actually decreases ghrelin, the hormone that stimulates your hunger, which in turn helps keep your hunger at bay. How much does it suppress it? That may depend on what type of exercise you do. Back in 2008, a UK study found that cardio training is more effective than resistance training in suppressing hunger for two hours after an activity. This is due to hormonal changes in the release of ghrelin and peptide YY. Hunger-stimulating ghrelin decreased in both activities, but peptide YY, the gut hormone that suppresses hunger, increased only during cardio. Keep in mind, these results could vary from individual to individual. Yet another study published in the Journal of Applied Physiology, found that exercise significantly lowers our response to food cues after exercise. Researchers found that exercise may lessen your desire to eat by altering how parts of your brain respond to the sight of food.
Rewarding yourself with food after a workout can turn into a pattern that is hard to break. Do you frequently go out for coffee and bagels with friends after your Saturday spin class? Or how about grabbing burgers and beers with the guys after a recreational basketball game? These sorts of behaviors can turn into a habit — one you’ll act on whether you’re feeling hungry or not. The key is to listen to the cues of your body. Reward yourself with something other than food — like a massage to ease your achy muscles.
Grab a small, healthy snack to curb hunger pangs. You’ve heard me say over and over that you can eat yourself through any workout. That is, you can exercise like crazy and then eat poorly (see the examples above) and basically negate all the hard work you’ve put in. What a waste! On the flip side, not adding calories back in when your body needs it could be a costly habit as well: Just as I encourage everyone to fuel their bodies with a snack consisting of carbohydrates and protein before a workout, eating a healthy snack (NOT a full-blown meal) after a workout is a good idea too. The period after a workout is known as the golden hour (45 to 60 minutes following training), when muscles absorb the most nutrients and energy-providing glycogen is replaced the most efficiently. A snack that contains both protein and carbs will give the best results. Here are a few ideas for healthy, post-workout snacks: a fruit smoothie made with low-fat yogurt or milk, a hard-boiled egg with a large pear, or a small apple with walnuts.
The Bottom Line: Don’t be afraid to work out because it will make you eat more. Exercise actually helps you eat less and burns extra calories.