Why Do You Pig Out After You Work Out?

By Sharon Liao

Before training for my first marathon, I prepped like crazy. I read running books, devised a plan, and scheduled workouts into my Google calendar. What I didn't anticipate was around-the-clock hunger. After a run, my stomach screamed for sustenance all day. "I'm run-gry!" I cried as I plowed through sleeves of crackers and cookies and stacks of pancakes. It's no wonder I didn't shed a pound -- and probably gained a few -- despite logging hundreds of miles in four months.

Research suggests that my experience is surprisingly common. In a Louisiana State University study, it was the dieters who worked out the most who didn't lose as much weight as they expected to. "Too often, people overcompensate for exercise," explains Mary Jane Detroyer, RD, an exercise physiologist in New York City. "That's one of the main reasons women don't get the weight-loss results they anticipate." Use these strategies to outrun your hunger so you can finally cross your weight-loss finish line.

Related: 12 Sneaky Ways to Slim Down Your Diet


Pack a Snack
Call it the workout conundrum: The most important window for refueling is also when you're the least hungry. "Exercise boosts the production of a feel-full hormone, called peptide YY, that temporarily dampens the appetite," says Enette Larson-Meyer, PhD, RD, an associate professor of human nutrition at the University of Wyoming. After a few hours, though, this effect ends, and you want to inhale everything in sight. "A common mistake women make is believing they can just wait for their next meal," Detroyer says. "By the time they sit down, they're starving."

If you've worked up a sweat for an hour or more, have a little something within 30 minutes of finishing, even if you don't feel like it. (A gentle yoga class or 30-minute walk doesn't require refueling.) "The ideal snack has carbs to refuel your energy stores and protein to help repair muscle tissue," Detroyer says. Shoot for 150 to 200 calories, such as a smoothie or a stick of string cheese with a few whole wheat crackers. If you exercise for more than 90 minutes, you'll need a more substantial, 200- to 250-calorie snack, like a turkey sandwich on whole wheat bread or a frozen waffle with peanut butter and sliced banana.

Avoid a Reward Mentality

You killed it at CrossFit this morning, so at lunch you order the french fries instead of a side salad. Ring a bell? "We feel that we've earned a treat or a big meal after a workout," Larson-Meyer says. According to a study in the journal Appetite, people who simply thought about exercise dished out 52 percent more of a snack mix than those who didn't. "The problem is that many women wind up taking in more calories than they burn," says Lauren Antonucci, RD, a sports nutritionist and the director of Nutrition Energy in New York City. Falling into this trap is even easier when you're training with friends; pasta dinners and post-workout brunches can create an atmosphere of indulgence.

To avoid undoing all your hard work, stick with your normal fare and portions, then wait 10 or 15 minutes and help yourself to more if you're still hungry. "This will keep you from automatically supersizing your meals," Antonucci says. Feel you deserve a delicious reward, darn it? Upgrade quality, not quantity: Treat yourself to fresh blueberries instead of your usual apple for an afternoon snack, or toast a slice of artisan whole-grain bread from the bakery instead of that ho-hum supermarket loaf.

Clutch a Water Bottle
That empty-pit feeling in your belly may not be triggered by hunger. The signs of mild dehydration, such as low energy and sleepiness, can dupe your brain into craving food. And because these signals start before you're even thirsty, it's important to drink water early and often during your workout.

"People can lose anywhere from 24 to 48 ounces of sweat for each hour of intense exercise," Detroyer says. To avoid feeling like a water balloon, sip 16 to 24 ounces one to two hours beforehand, then have another eight ounces 15 minutes before you head out. During your workout, take a few swigs every 15 or 20 minutes, and drink up afterward. If you're doing an intense workout, step on the scale before and after exercise. For every pound you've lost, sip 16 to 24 ounces of H2O to rehydrate.

Add Intervals

Challenging your body with speed bursts instead of just jogging may fast-track your weight loss. Intervals not only torch more calories than steady cardio, but they may also keep your appetite in check, according to a review in the Journal of Obesity. "During vigorous exercise, your body temperature rises," Larson-Meyer explains. "And because working muscles require more oxygen, your blood flow is diverted from the gut." Both of these factors work to suppress hunger, she says.

Need more reason to push yourself? Researchers from the University of New South Wales in Australia found that women who did 20 minutes of intervals on a stationary bike (eight seconds of sprinting followed by 12 seconds of recovery, repeatedly) three times a week shed 11 percent of their body fat after about four months, while those who cycled twice as long at a moderate pace actually gained fat. Intense exercise causes your body to release a greater amount of catecholamines, hormones that drive the fat-burning process, says study author Stephen Boutcher, PhD, an associate professor of preventive medicine. To ramp up your next bike ride or run, alternate between brief bursts of 80 to 90 percent of your max effort and the same amount of active recovery. Do this for 20 minutes.

Related: 6 Reasons You're Not Losing Weight


Do a (Calorie) Reality Check
Can't seem to shake those final five pounds? Chances are, you're cooking the calorie books -- and it's time for an audit. "Some women overestimate how much they burn during exercise," says Nancy Clark, RD, the author of Nancy Clark's Sports Nutrition Guidebook. In a study from the University of Ottawa in Canada, people who expended 200 calories during a brisk walk guessed that they had torched 825 calories and then ate an average of 557 calories afterward.

To bring your estimation down to size, keep in mind that your calorie burn may not be what you think -- or even what you're told -- it is. The readout on an exercise machine like an elliptical or a treadmill can overshoot that number by a lot. The only truly accurate measure is a treadmill test done in a laboratory. For a closer gauge at home, invest in a personalized device with a heart rate monitor, such as one from Garmin or Polar USA, or use our calculator below.

Raise the Protein Bar

Some women worry that bulking up on protein leads to, well, a bulkier physique. But getting more of the nutrient can actually help you slim down. According to one University of Washington study, people consumed an average of 441 calories fewer on days when their diet was 30 percent protein compared with when it was just 15 percent protein. "Eating protein blunts the release of ghrelin, a hormone that stimulates hunger and increases the release of peptide YY, a hormone that controls satiety," explains Heather Leidy, PhD, RD, an assistant professor of nutrition and exercise physiology at the University of Missouri. Her research revealed that having a protein-rich breakfast can help prevent unhealthy snacking later in the day.

"Active women require more protein to repair and rebuild the muscles that are broken down during exercise," says Jim White, RD, the owner of Jim White Fitness & Nutrition Studios in Virginia Beach and an Academy of Nutrition and Dietetics spokesman. Pumping up your intake can help you feel stronger in the gym -- and when facing temptation in the kitchen. Women who exercise regularly may need 0.5 to 0.75 grams of protein per pound of body weight, Clark says. For a 140-pound woman, that's 70 to 105 grams a day. To meet this quota, aim to incorporate protein at each meal: Start with a container of Greek yogurt with almonds at breakfast, top your lunchtime salad with beans and an egg, and have a serving of meat or fish at dinner. Seek out snacks that also pack protein, such as a turkey wrap or a banana or apple spread with nut butter.

Aim Low
Eating meals that are low on the glycemic index (GI) -- a measure of how quickly blood sugar spikes -- can keep you from feeling ravenous. In a study published in the Journal of Nutrition, women who ate a low-GI breakfast including muesli, yogurt, and fruit three hours before an hour-long walk were 44 percent less hungry in the afternoon and torched more fat than those who started their day with cornflakes, white bread, and jam.

Low-GI foods elicit less of a blood sugar response, which can encourage the body to recruit its fat stores for fuel, Clark says. "They also tend to be high in fiber and protein, which can fend off hunger," she says. On race day, you may need refined carbs because they can be easier on a sensitive stomach and break down more quickly into energy that your body can use. But on a daily basis, fill up on high-fiber grains and produce instead of more processed fare: steel-cut oats instead of instant and fresh peaches instead of the syrupy canned kind.

Related: What to Eat Before and After a Workout

The Eat Sheet

Preparing for a race requires long hours, so repay your body by giving it premium fuel. "What you eat can affect your energy levels, recovery time and even injury risk," says White.

1. Don't go carb crazy.
"All meals should contain protein to rebuild muscles, carbs to supply energy and fat to increase endurance," White explains. Strike a balance among whole grains, produce, and lean protein, with a bit of healthy fat as an accompaniment.

2. Time it right.

Schedule meals or snacks within two hours of exercising. "If you have a lunchtime class, have half of your sandwich beforehand and the rest of your meal afterward," suggests Antonucci. As with any other workout, you should eat within 30 minutes of finishing.

3. Plan ahead.
If you're running or biking for more than 90 minutes, pack some fuel -- about 100 to 250 calories for each hour -- says Clark. Easily digested carbs, such as raisins and dried pineapple, provide a quick dose of energy.

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