Sarcopenia is the name given to the characteristic loss of muscle mass and strength that occurs with aging. It is somewhere in the long process of being formally characterized as a disease, so in addition to the loose definition under which we could say that everyone suffers sarcopenia to some degree, there will be a formal definition in which only those with the greatest loss are said to be suffering sarcopenia. In that model, everyone else is undergoing "normal, healthy aging." I'm not much in favor of this scheme of categorization. It defines a loss of function and decline with defined causes that might be addressed as nonetheless being outside the scope of medicine, and thus propagates the current ridiculous situation in which regulatory agencies will not approve treatments for the effects of aging until they are in their final, severe stages. The mechanisms are the same under the hood, amenable to the same forms of potential therapy at any degree of resulting dysfunction.
An open question for sarcopenia, as is the case for many aspects of aging, is the degree to which it is caused by primary aging, the set of processes resulting from molecular damage that cannot be much affected or avoided at this time, versus secondary aging, the consequences of environment and lifestyle choices such as lack of exercise that can be avoided or minimized. Obviously, exercise and other forms of physical activity are fairly important when it comes to the state of muscle health, and here researchers add to the small mountain of data that exists to illustrate that point.
Although diseases related to the aging process are problematic themselves, they rarely occur in isolation and the effects of one may spark the onset of another. As such ailments progress, the importance of physical activity (PA) remains high, with previous research confirming that regular PA is essential for healthy aging. Specifically, PA plays a substantial role in lowering the risk of coronary heart disease, as well as many other age-related conditions. Although PA may have an indirect impact on some health aspects, it has a direct impact on muscle quality and quantity.
Sarcopenia, which was first described as the progressive decrease in muscle mass and strength during aging, is a syndrome that is directly affected by PA. Soon after sarcopenia was defined, muscle mass assessment had been recommended as the main sarcopenia diagnosing method. Later, several groups were formed for sarcopenia consensus on definition and diagnosis. These groups recommended including muscle strength and physical performance measurement as the additional methods for sarcopenia diagnosing.
Previous research has shown that physical inactivity contributes to the development of sarcopenia, and other studies have shown that PA increases muscle strength and muscle mass in older adults. Therefore, a strong link has emerged between PA and a lower prevalence of sarcopenia. Specifically, resistance training is generally considered to be the best countermeasure for preventing sarcopenia. Although many reviews and meta-analyses have summarized the effects of individual or combined interventions (e.g., resistance training and nutritional supplementation) on sarcopenia, a systematic review and meta-analysis of the effects of PA defined as general activity that requires more energy than resting metabolic rate (e.g., exercising, strengthening, walking, working in the garden, and so on) on sarcopenia has not been published. Therefore, the main aim of this systematic review and meta-analysis was to describe the relationship between PA and the presence of sarcopenia.
We searched for articles addressing the relationship between PA and sarcopenia. Twenty-five articles were ultimately included in the qualitative and quantitative syntheses. A statistically significant association between PA and sarcopenia was documented in most of the studies, as well as the protective role of PA against sarcopenia development. Furthermore, the meta-analysis indicated that PA reduces the odds of acquiring sarcopenia in later life (odds ratio 0.45). The results confirm the beneficial influence of PA in general for the prevention of sarcopenia.