People who lead a sedentary lifestyle are most likely to experience pronounced sarcopenia as they age. Sitting around on the couch is a good way to ensure serious loss of muscle mass late in life. Scientists reached this conclusion pretty far away from the couches of Earth -- NASA astronauts proved the first real test subjects for combating sarcopenia.
Astronauts lead a very sedentary existence. Spacecraft provide little room to move about and the effects of low gravity can wreak even further havoc on muscle mass maintenance. Curiously, in space, the opposite of the motor unit restructuring that we Earth-bound people experience takes place. Slow-twitch neurons tend to die off and fast-twitch neurons take up the slack. As a result, astronauts who spend a significant amount of time in weightlessness find their muscles tear more easily, since the FT neurons aren't used to controlling the larger number of fibers that ST neurons command.
Though it's an opposite condition, physiologists have found that sarcopenia and deep space muscle degradation share a common cure: resistance training (RT). For years, physicians have recommended 30 minutes of moderate daily exercise. In most cases, suggestions include exercises like walking and jogging. This type of activity is excellent for the cardiopulmonary system, and it does build some muscle, but resistance training that requires the use of weights to build muscle is often overlooked. With the results of studies since the late 1990s pointing to RT as a tool against sarcopenia, some therapists and physicians have started to recommend RT over aerobic exercise. After all, one must first be able to stand before one is able to jog. To stand, one must have muscle strength, which can be developed rather quickly under a RT regimen.
RT has proven that elderly people need not live out their days stooped over and shuffling about. Not only has adopting a resistance training regimen early in middle age has been proven to reduce the appearance of sarcopenia later in life, but RT regimens undertaken by the elderly has been shown to actually reverse sarcopenia by redeveloping muscle mass. Increasing protein intake also helps build muscle. These two breakthroughs combined could lead to a healthier senior adult population, one in which the signs of age aren't quite so obvious.
It's strongly recommended that a person -- especially someone of advanced age -- seek professional advice from a physician, certified personal trainer or physical therapist before beginning a resistance training program. Overexertion leading to torn muscles and even broken bones can happen easily if one lifts too much weight. What's more, some age-related diseases, like diabetes and dementia, can be exacerbated by resistance training.
It's worth the extra effort to visit a doctor and consult a physical therapist, as well as undertaking a weight lifting regimen. In one study, elderly people aged 78 to 84 who went on a RT program experienced an average increase in protein synthesis of 182 percent [source: Hasten, et al]. Another study, funded by the USDA, found that elderly participants who did RT for 45 minutes three times a week for 12 weeks saw an average increase of 32 percent for muscle fiber and a 30 percent increase in strength. Need more convincing? Go to the park and watch a few elderly people with sarcopenia.
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- Brown, Alan S. "Pumping iron in microgravity." NASA. January 22, 2004. http://spaceresearch.nasa.gov/general_info/pumpingiron.html
- Knight, John, Ph.D. and Nigam, Yamni, Ph.D. "Exploring the anatomy and physiology of ageing: part 10 - muscles and bones." Nursing Times. December 1, 2008. http://www.nursingtimes.net/exploring-the-anatomy-and-physiology-of-ageing-part-10-muscles-and-bone/1937855.article
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