If you’re trying to lose weight or simply avoid creeping weight, you’re likely adding exercise to your daily routine—good for you! Yet you notice a problem…the weight’s not coming off the way you want it to or worse, it’s sneaking upward. What’s that about?

Here’s one possibility: Research shows that many people overestimate the number of calories they burn through exercise and then eat back even more calories. But that’s only one of the common mistakes at the intersection between exercise and eating that could explain why you’re not reaching your weight goal, according to respected sports nutritionist Nancy Clark, MS, RD. Here’s the truth about exercise and calories—plus eight other mistakes that may be keeping your exercise from bringing the results you want…

Mistake: Overestimating the number of calories you burn through exercise and, as a result, eating more than you need. Exercise has a ton of benefits ranging from boosting bone and brain health to warding off diabetes and heart disease, but unless you’re working out at a very high level for a very long time, you’re not burning through a large number of calories. As an example, walking at a brisk 4 mph for 30 minutes burns about 200 calories (depending on your height and weight)—and that’s the number of calories in just one ounce of some nuts—barely a handful. Tip: Use a fitness chart or wearable fitness tracker to calculate what you’re really burning off when you exercise, and factor that correctly into your diet strategy.

Mistake: Counting on exercise alone for significant weight loss. Using the same example as above, you can quickly calculate how many 30-minute walks it will take to burn off one pound, or 3,500 calories—yes, 17.5! For exercise to contribute significantly to weight loss, it needs to be coupled with cutting calories. Tip: Although exercising more and eating less can combine to create the needed net calorie deficit, you really want to decouple the two things in your mind and put them into separate mental buckets. Exercising is vital for your health…and eating less is vital for losing weight.

Mistake: Having a one-and-done approach to daily exercise. If you work out for one 30-minute session per day and spend the rest of your waking hours at a desk or on the sofa, you aren’t capitalizing on exercise as much as you should for weight loss and overall health. Tip: Take a 24-hour view of activity and build on your formal workout. That could mean holding a walking meeting at the office instead of gathering around a conference table, adding an hour of gardening to your weekends, and jogging in place while you stream a TV show.

Mistake: Working out too soon after a meal. Exercise leaves many people hungry, and that can lead to eating more times during a day and taking in more calories than you had planned. Net result? You could end up with a weight gain, not a loss. Tip: One way to account for post-exercise hunger is to make sure that your exercise session does not come soon after any meal—but rather, soon before a regular mealtime. That way you can satisfy your body’s demand for fuel without adding extra calories (and in effect canceling out the calories you just burned). Just be sure to maintain—not add to—your food portion sizes.

Mistake: Thinking you need to replace electrolytes with a sports drink. Special “replacement” drinks are meant to boost fluid retention during heavy exercise, such as running a marathon. If you’re exercising three hours or more in the heat, they may be helpful. Otherwise, they’re not necessary. Electrolytes is essentially a technical term for salt. Chances are you’re already getting plenty of that. (A slice of bread contains about as much salt as a 12-ounce sports drink.) Tip: Water is all most people need to replace fluids after a typical workout, and it has no calories.

Mistake: Eating the standard three meals a day. Restricting yourself to breakfast, lunch and dinner is an old-fashioned way to fuel your body and can mean long stretches between meals. Instead, distribute your total daily calories somewhat evenly across four to six meals per day, depending on what works best for your schedule. Example: Try a hearty breakfast at 7 am, lunch at 11 am, a “second lunch” (bigger and better than a snack) at 3 pm and a lighter dinner around 6 pm. You may find it helpful to work with a registered dietitian (RD) to design a food plan specifically for you, one that includes the most nutrient dense foods to keep you fueled and feeling full. The referral network at SCANdpg.org can help you find a sports nutrition expert near you.

Mistake: Eating most of your protein at one meal. The body makes fast work of this essential nutrient. Protein in your food is best used to build and repair muscle in the first four hours after you’ve eaten, so you should include a serving of protein at every meal. Protein is filling, so it will help you curb your appetite, too.

Tip: Plan on 15 grams (g) to 30 g protein per meal (with larger people needing more than smaller people) if you’re eating four meals a day…or 10 g to 20 g per meal if you’re eating six meals a day. Healthy choices include two or three eggs (6 g of protein per one large egg)…turkey or chicken (3 oz/24 g)…fish (3 oz/19 g)…and black beans (1/2 cup/7 g). Looking for more nonmeat protein choices? Enjoy a banana with peanut butter, a handful of (high-calorie but healthful) nuts, cottage cheese or Greek yogurt.

What don’t you need? Protein shakes, a source of unnecessary calories for the average person—even for people who exercise. What’s more, packaged protein shakes are highly processed, commonly contaminated with heavy metals such as lead and arsenic, and they’re missing many of the nonprotein nutrients found in whole foods.

Mistake: Eating a large meal close to bedtime. Remember to think of food as fuel. You need more fuel during daytime hours when you are active and less when you are sleeping. Tip: Front-load your day by having more of your calories at breakfast. Resist the urge to eat after dinner—move any calories you’re in the habit of eating at night into the next day’s breakfast.

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