How to Maintain Muscle (Even When You're Not Working Out)

Wondering how to maintain muscle while recovering from an injury? Consider exercising the rest of your (non-injured) body. "If your left leg is injured, for example, there's benefit to training the uninjured leg," says David Hooper, Ph.D., C.S.C.S., an assistant professor of kinesiology at Jacksonville University in Jacksonville, Florida. "It has been shown to transfer to the injured limb to some degree." Yes, exercising one part of your body can help you keep muscle in other parts—crazy, right? (Just be sure to watch for any muscle imbalances if you train one side or muscle more than the others.)

You've probably seen creatine at your local supplement store, but it's also found in red meat. Creatine provides fuel for muscles and has been shown to be a solid option for how to maintain muscle strength and size when you're injured, says Jeffrey R. Stout, Ph.D., professor and director of the school of kinesiology and physical therapy at the University of Central Florida and author of the book, Essentials of Creatine in Sport and Health. 

Dutch researchers found that maintaining protein intake may help preserve muscle during a prolonged workout break (protein provides the body with amino acids, the building blocks of muscle). "Quality protein sources such as animal protein (poultry, eggs, fish, beef, low-fat dairy) and plant-based protein (soy, beans, legumes, vegetables, nuts, and seeds) should be included in every meal and snack," suggests Arizona-based registered dietitian and nutritionist Tiffani Bachus.

How much protein do you need to maintain muscle? "Aim for 3 to 5 ounces at each meal and 2 to 3 ounces at snack time," she says. (More here: How Much Protein Do You Really Need Per Day?)

Less activity should mean fewer carbohydrates: "When your body's active, carbohydrates are used for energy (along with fat)," says Bachus. When you're inactive? Excess carbs—just like excess of any kind of calories—are stored as fat. Bachus suggests consuming approximately 15 to 25 grams of carbohydrates at each meal and snack. (Try these high-protein, low-carb foods nutritionists love.)

Exercise your imagination on your off days. In a Journal of Neurophysiology study, 29 subjects had a cast placed on their non-dominant arm for four weeks. Half of the subjects imagined contracting their forearm muscles and flexing their wrists for five seconds (without actually doing it). The other half didn't do the mental imagery exercises. At the end of the month, those who performed the metal imagery only lost 24 percent of their strength compared to the 45 percent lost by the group who used their imaginations and maintained muscle mass. 

If you know you're going on vacation or foresee a crazy schedule next week, and are curious how to maintain muscle? Push yourself more this week. If you work harder than usual, your body will need more time to recover, allowing you to build muscle during your hiatus, says Hooper. (Read more about the Science of Building Muscle and Burning Fat.)