March 2021 Issue
Senior Wellness: Muscle Mass Retention
By Jennifer Van Pelt, MA
Vol. 23, No. 3, P. 18
Nutrition and exercise can help maintain strength and quality of life.
Muscle mass is lost as part of normal aging, affecting strength and mobility. Recently recognized as a disease process by the World Health Organization and included in the International Classification of Diseases, 10th Revision, sarcopenia is defined as a loss of muscle mass, muscle strength, and physical functioning. Older age is a primary factor, but many important modifiable risk factors such as nutritional deficiencies, hormonal changes, comorbidities (eg, diabetes, hypothyroidism), inflammation, and medications, also can contribute significantly to the development of sarcopenia.
A “downward spiral” to frailty and loss of mobility often occurs in older adults, as the loss of muscle mass and strength leads to inactivity, which further increases muscle wasting.1 Sarcopenia occurs in up to 22% of adults aged 65 and older; as age increases, so does prevalence. Older adults with sarcopenia are at higher risk of falls, fractures, functional decline, hospitalizations, and even death.2,3
What the Research Says
Research shows loss of muscle mass begins as early as age 30. After age 50, it occurs at a rate of 1% to 2% per year, and after age 70 by 4% to 5% per year.3,4 “The decline in strength over the lifespan is even greater than the decline in muscle mass,” says Nathan F. Meier, PhD, an assistant professor in the department of kinesiology at Concordia University Irvine in California. Research has shown that loss of strength occurs at a rate of 12% to 15% per decade after age 50, and that rate of decline increases further with each subsequent decade.3
Inactivity causes muscle mass and strength loss at an even higher rate. “After age 30, inactive adults can lose as much as 3% to 8% of their muscle mass each decade, and that rate is even greater after age 60,” says Heather Mangieri, MS, RDN, CSSD, a sports and wellness dietitian and published author who’s board certified in sports nutrition. It’s important that older adults understand what muscle mass loss can cause—loss of strength and physical functioning, two things that really affect older adults’ quality of life, she adds. “Retaining muscle mass gets harder as we age, which is why focusing on doing the right exercises and eating the right nutrients is important,” Mangieri says.
Recent research and international guidelines recommend nutrition and physical activity to prevent and treat sarcopenia.1-3,5 “For the aging adult, sarcopenia is preventable and reversible through exercise and diet, even in the very old,” Meier says. In a recently published study on physical activity and sarcopenia in older adults, Meier assessed the importance of lifestyle in limiting age-related declines in muscle mass and functioning.5 “In our study, the people who were physically active, maintained higher levels of fitness and strength, and avoided sedentary behavior had the lowest risk of having sarcopenia,” he notes, adding that, by increasing time spent being physically active, doing strength training, and sitting less, older adults can avoid unnecessary risk of sarcopenia and, subsequently, risk of falls, mobility issues, loss of independence, and lower quality of life.
Choosing physical activity that builds strength is the most beneficial in preventing sarcopenia, Meier emphasizes. “To enhance strength, individuals should perform a range of exercises that target the whole body—legs, hips, chest, abdomen, shoulders, arms—for at least eight to 12 repetitions twice weekly. Two to three sets of each exercise provide greater benefits,” he explains. Strength exercises should be performed until it’s difficult to do another repetition, as is recommended by US physical activity guidelines, Meier adds.6 Over time, the weights used in each exercise can be increased as strength increases. Meier notes that just modest improvements in strength have substantial benefits to physical function and balance.
But formal strength training with weights isn’t the only way to address muscle loss. “It can include simple resistance exercises using their own body weight, resistance bands, or other items they have in their home (eg, filled water bottles as handweights). Doing strength training doesn’t need to involve going to a gym or buying special equipment and can be done simply at home,” Mangieri says.
In addition, other physical activity, such as low-intensity cardiovascular exercise and common household work, is beneficial. Being physically active in any way is helpful in maintaining muscle mass, Meier says, including activities the individual enjoys most. “Physical activity does not have to fit any preconceived notion of ‘exercise,’” he says. Doing housework, going for walks, dancing, and gardening all can be beneficial activities. Any activity that increases heart rate enough to be able to talk but not sing (a good gauge of moderate intensity) counts toward being active, Meier says.
In Meier and colleagues’ research study, cardiorespiratory fitness was associated with a significantly lower prevalence of sarcopenia and low muscle mass. “Avoiding being sedentary, as well as breaking up long periods of sedentary behavior with movement, is also protective,” he adds. Sedentary time of less than eight hours per day was associated with a lower risk of having low muscle mass in their research study.5
Nutrition also plays a vital role in preserving muscle mass. Protein intake should be a primary focus when providing dietary guidance, Mangieri says. Research has shown that higher daily protein intake is beneficial for older adults in maintaining positive nitrogen balance and preserving muscle mass.1,2,7 Daily recommended protein intake is 0.8 g/kg; some researchers have proposed 1 to 1.3 g/kg/day for older adults. A 120-lb older adult, then, would need 54 to 70 g protein each day, Mangieri says.
The best thing dietitians can do to help older adult clients reduce the risk of sarcopenia is to discuss the importance of muscle mass and the consequences of age-related muscle loss and encourage them to keep moving and using their muscles, Mangieri says. “Time spent being active and building strength is like saving for retirement. Each training session is like a deposit; over time, that investment will pay dividends,” Meier says.
In addition to helping with planning regular exercise, Mangieri says dietitians can help older adults with the following:
• Emphasize the importance of regular exercise to help preserve muscle by explaining the effects of age-related muscle loss on their daily physical functioning in a way they understand.
• Discuss benefits of proper diet and exercise in the context of what’s important to them, such as carrying groceries without assistance.
• Determine their daily protein needs and encourage them to distribute their protein intake throughout all their meals.
• Educate them about protein-rich foods and assist them with selecting high-quality protein sources that meet their health needs. For example, older adults with poor dentition or difficulty chewing may need softer or easier-to-chew options.
Nutrition professionals have the important role of assisting older adult clients in putting together a simple combination plan of exercise and nutrition to help them maintain their muscle mass and prevent its loss as they age, Mangieri says.
— Jennifer Van Pelt, MA, is a certified group fitness instructor and health care researcher in the Lancaster, Pennsylvania, area.
1. Fuggle N, Shaw S, Dennison E, Cooper C. Sarcopenia. Best Pract Res Clin Rheumatol. 2017;31(2):218-242.
2. Dent E, Morley JE, Cruz-Jentoft AJ, et al. International Clinical Practice Guidelines for Sarcopenia (ICFSR): screening, diagnosis and management. J Nutr Health Aging. 2018;22(10):1148-1161.
3. Billot M, Calvani R, Urtamo A, et al. Preserving mobility in older adults with physical frailty and sarcopenia: opportunities, challenges, and recommendations for physical activity interventions. Clin Interv Aging. 2020;15:1675-1690.
4. Bell KE, von Allmen MT, Devries MC, Phillips SM. Muscle disuse as a pivotal problem in sarcopenia-related muscle loss and dysfunction. J Frailty Aging. 2016;5(1):33-41.
5. Meier NF, Lee DC. Physical activity and sarcopenia in older adults. Aging Clin Exp Res. 2020;32(9):1675-1687.
6. King AC, Whitt-Glover MC, Marquez DX, et al. Physical activity promotion: highlights from the 2018 Physical Activity Guidelines Advisory Committee systematic review. Med Sci Sports Exerc. 2019;51(6):1340-1353.
7. Witard OC, McGlory C, Hamilton DL, Phillips SM. Growing older with health and vitality: a nexus of physical activity, exercise and nutrition. Biogerontology. 2016;17(3):529-546.