[Sarcopenia: a physical marker of frailty]

Sarcopenia is defined by loss of muscular mass, strength and quality that occur in elderly. Multiple factors underlie this process: low physical activity, low steroids hormones, increase of cytokines, loss of motoneurons, decrease of protein synthesis...However, the role of these factors is not yet well understood and consensual clinical definition and assessment are still needed. It has become an important area of research because of its frequency and the influence in the disability of old people. It is a major component of frailty. So far, no pharmacological treatment has proven definitive evidence to treat or prevent sarcopenia. Nevertheless, it needs a multidimensional approach based on physical activity and prevention of malnutrition.