Aging and Muscle Mass
From childhood to early adulthood, we build muscle and bone to support the growing skeleton. Researchers estimate people reach peak muscle mass sometime in their 40s. After that, many people begin to lose muscle at an average rate of one-half pound a year.
Sarcopenia is a condition characterized by a significant loss of skeletal muscle mass and strength. Studies suggest it affects up to 15 percent of Americans over 65 and half of those over 80. The loss of muscle mass and strength affects balance, posture, mobility and endurance. Patients may walk with a slow, unsteady gait and are at higher risk for falls. Simple daily activities, like carrying groceries, getting up from a chair, rising out of bed or climbing stairs can be difficult.
The Need to Tone
The best way to combat loss of muscle mass and strength is to perform strength training exercises. Health experts say all adults should do at least 30 minutes of aerobic exercise a day AND muscle-strengthening exercises 2 or more days a week. Strength training builds strong bones, as well as muscles, and can improve a person’s overall quality of life. Recent research suggests strength training may also reduce blood pressure, improve cholesterol levels and reduce the risk for diabetes.
Jessica Matthews, Spokesperson for the American Council on Exercise (ACE), says the need for strength training increases around 40, when muscle mass starts to decline. Strength training can be done in a variety of different ways, using machines, free weights, tubes, or even body weight for resistance. The key is to work all the major muscle groups.
ACE recommends performing 8 to 12 repetitions until you are fatigued. You should do at least one set of repetitions, and then gradually build on that number. When you are able to complete 12 repetitions without tiring, increase the amount of resistance by 5 to 10 percent.
Matthews has two exercises she recommends for building strength in key areas of the body:
The bodyweight squat builds muscles in the hips, buttocks, abdomen and legs. From a standing position, hold your chest out and push your hips back, shifting your weight onto your heels. Lower the hips while keeping the core muscles tight and the spine straight. Continue lowering the body until the thighs become parallel to the floor and the heels start to lift. Then, while pushing the heels flat on the floor, bring the hips and torso up to the starting position.
The traditional crunch strengthens the abdominal muscles and builds core strength. Start by lying on your back with your knees bent. Place your hands behind your head and squeeze your shoulder blades together, keeping the elbows apart. Contract the abdominal muscles while slowly pulling up your torso, keeping your feet and lower back completely on the floor. Once the upper back is off the floor, hold the position briefly. Then, slowly, and in a controlled manner, lower the torso back to the mat. When doing crunches, you should exhale during the rising phase and inhale while lowering.
AUDIENCE INQUIRYIf you have specific questions about strength training, speak with a trainer or your health care provider. For general information:
American Council on Exercise, http://www.acefitness.org
Centers for Disease Control and Prevention, http://www.cdc.gov/physicalactivity/everyone/guidelines/adults.html
BIBLIOGRAPHYAlfieri, Fabio, et al., “Functional Mobility and Balance in Community-dwelling Elderly Submitted to Multisensory Versus Strength Exercises,” Clinical Interventions in Aging, August 9, 2010, Vol. 5, pp. 181-185.
Alley, D., et al., “Hospitalization and Change in Body Composition and Strength in a Population-based Cohort of Older Persons,” Journal of the American Geriatrics Society, November 2010, Vol. 58, No. 11, pp. 2085-2091.
Burton, Louise, and Deepa Sumukadas, “Optimal Management of Sarcopenia,” Clinical Interventions in Aging, September 7, 2010, Vol. 5, pp. 217-228.
Hanson, Erik, et al., “Effects of Strength Training in Physical Function,” Journal of Strength and Conditioning Research, December 2009, Vol. 23, No. 9, 2627-2637.
Kjaer, Michael, and Jakob Jespersen, “The Battle to Keep or Lose Skeletal Muscle with Ageing,” The Journal of Physiology, January 15, 2009, Vol. 587, Pt. 1, pp. 1-2.