Muscle mass: Use it or lose it

Muscle mass: Use it or lose it

Some people perform incredible feats of strength and endurance well into their retirement years. But you don’t have to bench press 300 pounds or run a marathon to show off the benefits of strength training.

National Institute on Aging (NIA)-supported researchers, in 40 years of studying strength training, have identified multiple ways it can benefit older adults, including maintaining muscle mass, improving mobility, and more healthy years.

Age-related mobility limitations are a fact of life. NIA reports about 30 percent of adults over age 70 have trouble walking, getting up out of a chair, or climbing stairs. Such limitations are also linked to higher rates of falls, chronic disease, nursing home admissions, and mortality.

A big culprit for losing physical abilities is the age-related loss of muscle mass and strength, which is called sarcopenia. Typically, muscle mass and strength increase steadily from birth and reach their peak at 30 to 35 years of age. After that, muscle power and performance decline slowly at first, and then faster after age 65 for women and 70 for men. However, decline of strength and power can be substantially slowed down by maintaining an active lifestyle. While there is no way to fully stop the clock, it’s possible to increase strength with exercise, which can help maintain mobility and independence.

By studying people’s limits and variability, researchers aim to provide evidence-based advice on how regularly moving and challenging muscles may help increase years of optimal health.

Roger Fielding, associate director of the Jean Mayer USDA Human Nutrition Research Center on Aging at Tufts University (located in the Boston, Mass. Area), has looked at how muscle-training exercises benefitted a community-based group of older adults with moderate mobility limitations. He noted strength training (also known as resistance training) is different than aerobic exercise such as running, cycling, or walking. Weightlifting, either with machines or free weights, is one type of resistance training. Others include using medicine balls or resistance bands, or body weight-bearing exercises such as pushups, squats, or yoga. Resistance training requires muscles to contract to lift a heavy object against the pull of gravity.

Fielding and his colleagues have found that the best recipe for improving physical function and avoiding disability is a combination of walking and resistance training. In NIA-supported research, volunteers participate in small group exercise sessions led by a physical fitness trainer. The goal isn’t a perfectly chiseled abdomen or achieving exceptional feats of strength. Rather, participants use ankle weights and dumbbells, or adapt exercises to use their own body weight.

The group sessions also encourage bonding and accountability among participants, which helps keep them motivated and sticking with it, according to Fielding.

Fielding doesn’t just talk the talk, he does strength training himself.

“I’ve always run three or four times per week, but about three years ago, I started making strength training part of my routine, and I feel stronger,” he said. “My goal is to be able to do things I enjoy, including downhill skiing, as long as I can, and the best way is to try to stay active.”

While strength training is great for otherwise healthy older adults, what about those who are overweight or living with obesity?

Dr. Dennis Villareal, a professor at the Baylor College of Medicine in Houston, Texas, works with obese older adults, including volunteers from a nearby Veterans Affairs hospital. “We work at the intersection of two big changes for society–aging and obesity,” Villareal said. “About one-third of older adults have obesity, and that number is rapidly expanding.”

According to Villareal, it’s not well understood that older adults with obesity can also be frail, which creates a vicious cycle of mobility and independence loss as the years and pounds add up.

“Folks with obesity need more muscle mass to carry their body weight,” Villareal said. “When they get older, they can’t compensate by producing more muscle mass, so you get sarcopenic obesity, which is the worst of both worlds.”

Villareal’s research team found that a healthier diet combined with a workout mixing aerobic exercise, resistance training, and balance was most effective for helping reverse frailty.

“As the relationship between body mass and muscle becomes more positive, participants lose more fat than muscle, so the relative sarcopenia is improved significantly,” he said.

Villareal notes that starting slow and attending regular group classes are important steps to building confidence and connections among participants.

As if it wasn’t already tough enough to be motivated to exercise, unanticipated factors such as the COVID-19 pandemic and severe weather events can prevent some people from exercising indoors with larger groups. So NIA-supported scientists from the Wake Forest University School of Medicine in Winston-Salem, N.C. are researching ways to bring resistance training to the homes of older adults who are trying to lose weight.

One way is known as Incorporating Nutrition, Vests, Education, and Strength Training in Bone Health (INVEST). Barb Nicklas, a Wake Forest professor of gerontology and geriatric medicine, and other researchers are studying if participants wearing a weighted vest for eight hours a day can help prevent the bone-density loss that often occurs with weight loss. So far, volunteers who wore the weighted vest slowed down hip bone-density loss compared to the weight-loss-plan-only group. This could reduce the risk of debilitating hip fractures.

Researchers offer these tips for staying strong:

Know what to expect. First, don’t try to compare yourself to younger people. Everyone is unique and ages differently.

“A 60-year-old is very different from an 80-year-old. We need to be careful about lumping all older people into the same category,” Nicklas said. “Aging starts at birth, and throughout our lifespans, exercising to help prevent disease and disability is very important. Movement, strength, and balance training is important at any age, but we need to adjust our expectations.”

Move mindfully. Low bone density and muscle strength are associated with increased falls and fractures. Exercises that incorporate balance and movement, such as tai chi and yoga, can improve strength and help prevent falls.

Make it part of your daily routine. If online or in-person group classes aren’t your thing, everyone can still work exercise into their daily routines. “Just walk more,” Villareal said. “Walk around the house or office, walk to the store. In the office you can take brief exercise or stretching breaks every 15 or 20 minutes and try to use all your muscles.”

Keep it fun. “Find things that people want to do and like to do, not just exercise for exercise’s sake,” Fielding said. “Lots of things count as exercise: It doesn’t have to be running or going to the gym or riding a stationary bike. It could be dancing, gardening, housework,” or playing with grandchildren.

Set realistic goals. Fielding said a good goal “is about 150 minutes per week of moderate-level exercisebut you see benefits even at lower levels than that. Try to get strength training in the mix one to two times per week.”

The bottom line, he said, is “any physical activity is better than none. Even a couple minutes per day matter, and small changes lead to big improvements.”

 

Source: National Institute on Aging, a federal health agency.

Workouts with free weights is one way to build and maintain strength.