When it comes to having enough energy to lift weights, build muscle and then maintain it, what you eat makes a difference. Even if you can lift a ton of weight, if your diet consists of simple carbohydrates, fatty foods and sugary drinks, much of your hard work will be in vain because protein is muscles’ foundation. When you lift a weight heavy enough to challenge your muscles, it causes the muscle fibers to literally tear. But then, as the muscle tissue heals, it becomes stronger than it was. In order to build new, stronger muscle than you’ve broken down with exercise — a condition called positive protein balance — you need adequate protein in your diet.
Protein = Power
Muscle tissue is about 15 to 20 percent protein, so if you want to maintain the muscle you’re building, make sure you’re eating enough protein. How much is enough? “Casual exercisers, or people who exercise for overall health and fitness, need 0.5 to 0.9 grams of protein per pound of body weight daily,” says Cindy Moore, MS, RD, director of nutrition therapy and a group fitness instructor at the Cleveland Clinic. (Competitive athletes need more.) For a person who weighs 150 pounds, that adds up to 75 to 135 grams of protein a day. You can get enough by eating foods such as fish (24 grams per three-ounce serving), poultry, eggs, low- and nonfat dairy (eight grams per eight ounces of milk), soy-based foods, beans (15 grams per cup) and lentils. If your day-to-day diet lacks protein, you can boost your intake with protein shakes and supplements, but Moore always recommends whole foods first.
Count on Complex Carbs
Thanks to the low-carb diet craze of a few years ago, carbohydrates got a bad rap. But if you want to have enough energy for exercise to build stronger muscles, you need to eat them. “Carbohydrates, which our bodies store as glycogen, are the body’s preferred energy source,” says Amy Jamieson-Petonic, MEd, a registered dietitian and the director of wellness coaching at the Cleveland Clinic. “They provide fuel to working muscles during exercise, maintain blood sugar levels and help brain function.” The human body stores about 150 grams of glycogen, which isn’t much. That’s why we need to continually fuel ourselves to avoid hitting the wall. The bottom line: If you avoid carbs, your exercise performance suffers.
So how many carbs should you get? “If you eat a 2,000-calorie-a-day diet, about 1,200 of those calories [300 grams] should come from carbohydrates,” Moore says. She advises choosing complex carbs, the ones that do double duty by adding fiber to your diet, including whole-grain bread, pasta and cereal, brown rice, couscous, and vegetables. If possible, eat foods that provide long-lasting energy, such as yogurt, oatmeal with bananas or half of a whole-grain bagel with peanut butter.
What you eat after a workout matters too. “There is a 30- to 45-minute window following exercise when the muscles are most likely to replenish the glycogen you used up during exercise,” Jamieson-Petonic says. Go for foods that are quickly absorbed, such as low-fat chocolate milk or a turkey sandwich on whole-grain bread. Note, though, that refueling is mostly important for high-intensity exercisers and high-performance athletes. If you’re exercising lightly or moderately, you probably don’t need a post-workout snack.
The Bottom Line on “Energy” Bars
It’s a mistake to think you need bars or nutritional supplements to give your body the fuel it needs for exercise. “Whole foods contain so many nutrients, including protein, vitamins and minerals,” Moore says. Of course, protein bars are super convenient, and there’s no harm in occasionally eating one for a pre-exercise snack, or even as a last-ditch breakfast option. Just know that they are not all created equal. Some contain unhealthy fats and are loaded with sugar and/or high-fructose corn syrup. Plus, energy bars often pack 200 calories (or more) in a dense, little (not very filling) package.