How Do Carbohydrates Support Muscle Health?

Carbs may not get as much credit as protein, but this macronutrient is also crucial for muscle health. Carbohydrates are stored in your muscles and liver as glycogen, which is used as energy to spark muscle contractions.

“I think of protein as a macronutrient of building and repair, and carbohydrates as a macronutrient of energy,” explains sports nutritionist and strength coach Steph Gaudreau, CISSN, NASM-CPT.

Getting enough carbs is critical, especially if you’re active. “If we have adequately stocked up our glycogen stores, we’re going to have enough energy to get through our workouts and push our strength training a bit harder to see better results,” she says. And that can mean more significant muscle maintenance and muscle building.

If your body is forced to break down protein for energy, you may not have enough left for muscle maintenance and repair, leading your muscles to shrink and weaken over time.

Stocking plenty of glycogen in your muscles and liver is also essential to stop your body from dipping into your protein reserves for energy. “If we don’t have adequate glycogen stores to keep our bodies going, what you see — especially in the context of low calorie and low carb intake — is the body can turn to other substances,” she notes.

If your body is forced to break down protein for energy, you may not have enough left for muscle maintenance and repair, leading your muscles to shrink and weaken over time.

Carb needs vary depending on your sex, age, body weight, and activity level, so it may take some experimenting to find the amount that works for you (learn more at “What Is Your Unique Carbohydrate Tolerance?“). Gaudreau suggests getting at least 40 percent of your daily calories from carbohydrates and gradually increasing that amount if needed. If you do a lot of endurance training, you may need to go as high as 60 percent.

Tips to Optimize Your Carb Intake

• Steel-cut oats, sweet potatoes, pumpkin, spaghetti squash, brown rice, black beans, quinoa, and lentils are great sources of complex carbohydrates that offer plenty of fiber.

(Learn more about the importance of eating fiber-rich foods at “Why You Need to Eat Fiber.”)