13 Post-Gym Mistakes that Could Ruin Your Workout

These habits could sabotage your weight loss or make you more likely to get injured. Avoid them!

1/13 View as List

You reach for a sports drink

iStock/Tom Young

While it’s important to stay hydrated after a workout—even a 1 percent decrease in hydration can significantly impact your athletic performance—you probably don’t need a sports drink, which can contain unnecessary calories. (These are signs you could be drinking too many calories.) You don’t need to replace electrolytes unless you’ve had an intense workout that lasted more than an hour, so plain water is probably sufficient, says Jessica Crandall, RDN, CDE, spokesperson for the Academy of Nutrition and Dietetics. “I just encourage hydration through water because that’s the best way to get adequately hydrated,” she says. Are you showing signs of dehydration?

You skip the cool down


Stopping too fast could make you feel sick if your body doesn’t get the chance to recover. Your temperature rises and your blood vessels widen during physical activity, and your body needs the chance to get them back to normal, says Melissa Leber, MD, FACEP, assistant professor of orthopaedics and emergency medicine at Mount Sinai Hospital. “You can feel very light-headed if you don’t cool down and go straight to the shower,” she says. (Watch out for these clear signs you're about to faint.) If you have a fitness tracker, make sure your heart rate is down to 100 or lower before you wrap up your workout.

You don’t stretch


For the biggest gains in flexibility, stretch right after your workout. Because your muscles are already warm from the exercise, they’ll be able to lengthen more, so you can build a better range of motion. Stretching might not give you immediate injury protection, but your body will be better primed in the future. “It doesn’t prevent injury unless you’re looking down the road,” says Dr. Leber. “If the range of motion in your joints is better, you’re less prone to injury.” This is the best stretch to undo the effects of siting all day.

You wait hours to eat again


Refueling within two hours of a workout is crucial for recovery. Carbohydrates replenish the stored energy your muscles used, and protein helps repair the small tears in your muscles that exercise creates, says Alissa Rumsey, MS, RD, CDN, CSCS, spokesperson for the Academy of Nutrition and Dietetics. Aim for 15 to 20 grams of protein for prime recovery, says Crandall. “That protein, when it comes back in, is helping you replenish and re-heal that muscle so you get growth instead of being degraded,” she says. “If you’re not refueling, it’s breaking down further.” Do you need more protein in your diet?

Or you eat too soon


Exercise tends to suppress your hunger initially, but later in the day your hunger hormones will surge, says Rumsey. If you eat a snack within an hour of a workout just because you think you should, you might end up eating double. “That immediate post-workout snack is just additional calories,” she says. Check out these other times snacking can ruin your diet.

You don’t look at your protein bar’s nutrition facts


Protein bars can be a convenient way to refuel after a gym session, but take a peek at the nutrition label before tearing into it—and look closely, because some have two servings in a single bar, says Crandall. “Sometimes protein bars can be really high in sugar and are glorified candy bars,” she says. Others use sugar alcohol as a sweetener, making them look lower in sugar, even though they can be bad for you too, says Rumsey. Your body can’t process sugar alcohol, so you might end up feeling bloated, crampy, or just plain unsatisfied. “It has a sweet taste, but there are no calories associated with it,” says Rumsey, “so the brain isn’t registering it, and we often crave more sweets later in the day.” Here are more foods GI doctors say to avoid.

You head straight to the smoothie bar


Those smoothie bars seem like a convenient, healthy way to refuel, but steer clear—many are calorie bombs with two to four cups of fruit, not to mention sneaky sugar sources. “When juice is used as a base, it adds a lot of calories and also a lot of simple sugars,” says Rumsey. “What you’re drinking is similar to a soft drink.” For a post-workout drink that actually is as healthy as it seems, make your own smoothie using a cup of fruit, a handful of leafy greens, four to six ounces of plain Greek yogurt, and a handful of chia seeds or nuts, she says.

You reward yourself with food


After a day at the gym, you might find yourself ravenous and looking for an indulgent treat to reward yourself for a vigorous workout. But if you give in to those cravings, you could end up undoing all your hard work, says Crandall. After all, the 300 calories you burn in a 30-minute doesn't exactly give you wiggle room for a free-for-all at the drive-thru. “You can’t outrun your mouth,” she says. “No matter what you’re doing from a physical fitness standpoint, it’s easier to eat than to work out.” Use these science-backed tips to stop your strongest food cravings.

Or you try to make it an “extra-healthy” diet day


On the flip side, some people are so empowered by a great workout that they try to work harder on their diets by skipping meals and cutting too many calories. But your body still needs the fuel, so make sure you don’t go overboard with the calorie cutting. “On days you work out, don’t see it as a diet day—see it as a well balanced day,” says Dr. Leber. Instead of skimping on dinner, she recommends eating a well-rounded meal with four to six ounces of lean protein, a small serving of carbs like pasta or rice, and a vegetable. Steal these other diet secrets from nutritionists.

You meet friends for post-workout drinks


If you’re heading to happy hour right after a gym session, you might want to stick to just one drink. Alcohol and protein are both synthesized in the liver, so heavy drinking could get in the way of your recovery after a workout. “When drinking a lot of alcohol, the liver is working to process the alcohol, and not the protein so much,” says Rumsey. Here are more ways your body benefits when you stop drinking alcohol.

1/13 View as List

Want to stay smart and healthy?

Get our weekly Health Reads newsletter

We will use your email address to send you this newsletter. For more information please read our privacy policy.