A recent study analyzed the combined effects of both dietary and physical activity interventions on sarcopenia and found that in 79 percent of the studies, muscle mass increased with exercise, with an additional effect of nutrition seen in 23.5 percent of studies.

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Most people understand the importance of protecting their hearts and brains as they age, but muscle health is often forgotten. This is a dangerous mistake, as good muscle health is crucial for our ability to remain healthy and independent with advancing age. Up to one-third of older adults are at risk because they suffer from age-related muscle loss, or sarcopenia._[1]

What Is Muscle Health?

Your skeletal muscle powers your body movements, is essential to maintaining stability, and helps maintain blood sugar balance. Without good muscle health, strength, mobility, and function all decrease, while fatigue, falls, fractures, and metabolic disorders like obesity and diabetes increase.

The total weight of your skeletal ­muscle is called your muscle mass. Having adequate muscle mass ensures that you can move, but is also essential to basic survival. Muscle is made primarily of protein, which is made of individual amino acids. Many tissues and organs, such as the skin, brain, heart, and liver, need these amino acids to function.

When dietary protein intake is insufficient, muscle protein serves as the principal reservoir to replace used-up amino acids. This protein reservoir also supports the immune system and other bodily systems during healing or recovery from exercise, illness, surgery, or traumatic accidents.

Muscle Function

Sufficient muscle mass, however, is just the beginning. Good muscle function is even more significant. Three primary factors determine good muscle function.

1. Quality muscle has more mitochondria. These are the powerhouses within your cells that use oxygen to turn glucose and fat into adenosine triphosphate (ATP). ATP is the gasoline for your muscle cells. More mitochondria means more energy and better capacity to burn fat. Further, in healthy muscles, the mitochondria are more active and efficient, generating less oxidative stress._[2]
2. Quality muscle has less fat. The more fat-laden your muscle tissue, the more you’re likely to succumb to age-related declines in strength, mobility, and functioning. In fact, fatty muscle is more likely to cause weakness and loss of mobility than loss of muscle, so in some ways it’s worse to have fatty muscle than dwindling muscle. Furthermore, fat muscle tissue is less responsive to the hormone insulin, so it can’t control blood sugar as well as lean muscle can. This can lead to weight gain and diabetes.
3. Quality muscle has a healthy balance of fibers. Muscle is made up of bundles of two types of fibers: slow twitch and fast twitch. Slow twitch are responsible for long-duration, low-intensity activities such as walking. Fast twitch are responsible for short-to-moderate duration, moderate-to-high intensity activities, such as most weight training and sprinting. With insufficient fast-twitch fibers, actions as basic as rising from a chair, climbing steps, or regaining balance can become difficult or impossible._[3]

Age-Related Declines in Muscle Health

As we age, muscle mass and all three factors of healthy muscle function decrease. The end result is diminished strength and physical performance, which lead to:

• Mobility impairments
• Weakness
• Fatigue
• Increased risk of death, infection, and falls
• Slower healing
• Overall diminished quality of life

The decline in muscle health associated with aging is known as sarcopenia and it increases the risk of “physical disability, poor quality of life, and death._[1,4-6]

As your muscle health declines, you’re much more likely to die of any cause. In fact, your muscle health may be more (or just as) important for predicting death than many other common risk factors, including your weight, diet, and smoking.

Preserving Independence

It is one of the strongest indicators for functionality and quality of life._[7,8] Just think about how important it is to be able to get up out of a chair to do what you need to do, like go to the bathroom, dress yourself, shop, or cook.

Muscle function also helps prevent falls. People of all ages fall, of course, but those with poor muscle health are both more likely to fall and more likely to be severely injured._[9,10] If you have good muscle mass and strength, at the very worst you will break your hand or wrist when your hands immediately come out to break the fall. Without good muscle mass and strength, particularly in the upper body, it is not possible to protect yourself and break the fall. The result is often a broken hip. While a broken wrist is an inconvenience, a broken hip can be a death sentence.

What to Do About Sarcopenia

The good news is that sarcopenia is very effectively treated with nutrition and exercise. At any age, you can regain muscle health for improved vitality and quality of life.

1. Age Ageing. 2014 Nov;43(6):748-59.
2. Biochim Biophys Acta. 2014 Apr;1840(4):1276-84.
3. Osteoporos Int. 2010 Apr; 21(4): 543–559.
4. Am J Med. 2014 Jun;127(6):547-53.
5. Geriatr Gerontol Int. 2015 May 28.
6. J Am Med Dir Assoc. 2015 Jul 1;16(7):607-13.
7. Arch Gerontol Geriatr. 2012 Sep-Oct;55(2):e9-13.
8. Exp Gerontol. 2015 May 13;69:103-110.
9. Clin Rheumatol. 2015 Apr 26. [Epub ahead of print]
10. J Bone Joint Surg Am. 2015 Mar 4;97(5):429-37.

Originally published in 2014 and updated.