Sure, you’ve heard about osteoporosis, but do you know about sarcopenia?

Just as bone loses density as you age, your muscles also lose mass, which compromises their strength, power and ability to function. The loss kicks in earlier than you may expect: Starting in your 30s, you can lose about 6 pounds of muscle per decade!

“The real danger with sarcopenia is that it relates to a lower degree of mobility and strength, and a higher risk of falling,” says Thomas Lang, who holds a doctorate in chemistry and is a professor in the Department of Radiology at University of California, San Francisco. “It really has a big impact on your ability to carry out the activities of daily life.”

To make matters worse, muscle loss and bone loss often go hand in hand -- which can really put you at risk for falls and fractures.

While losing some muscle mass is a natural biological process associated with aging, loss of strength and mobility as you age is not inevitable. To maintain muscle mass and stay youthful and strong, focus on the following:

Pull more than your weight.

Doing progressive strength-training exercises -- by lifting weights or using resistance bands or kettlebells -- two to three times per week can help you build and maintain muscle, says Wayne Westcott, who holds a doctorate in physical education and is the fitness research director at the South Shore YMCA in Quincy, Mass. An added bonus: The more muscle you have, the higher your resting metabolic rate will be, which means you'll burn calories at a faster rate -- even when you're not exercising, Westcott adds.

Take a hike -- and make it uphill

Most forms of aerobic activity are beneficial for overall health, but activities involving resistance really make a difference in preserving muscle mass and strength. To that end, walking up hills or stairs can help slow muscle loss because you’re forcing your muscles to work against gravity, says Westcott.

Consume enough protein

Research from The University of Texas Medical Branch at Galveston suggests that consuming 25 to 30 grams of protein in each meal can stimulate the synthesis of muscle. Consuming the essential amino acid leucine (present in soybeans, beef and fish) also may benefit muscle maintenance. “Consuming extra protein and carbohydrates -- by having chocolate milk or a yogurt smoothie -- before, during or after exercise will enhance muscle gains from strength training significantly,” says Westcott.

Get enough of the right micronutrients

Vitamin D may be important for preserving muscle function and muscle mass, according to new research from Australia. In addition, research from Johns Hopkins University in Baltimore suggests that a higher intake of carotenoids (found in carrots, cantaloupe, sweet potatoes and butternut squash) and vitamin E is associated with greater muscle strength as people get older.

While you can't stop those birthdays from coming, you can feel younger than your biological age by keeping your muscles strong.

Photo Credit: @iStockphoto.com/TimMcClean

Stacey Colino has written for The Washington Post health section and many national magazines, including Newsweek, Real Simple, Woman's Day, Self, Marie Claire, Cosmopolitan, Glamour, Parenting, Sports Illustrated and Ladies' Home Journal.

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