Factors contributing to the variability in muscle ageing.

Ageing is accompanied with a progressive loss of muscle mass and force generating capacity. Ultimately, the muscle wasting and weakness may dramatically impact on mobility and the quality of life, where the elderly has increasing problems with performing activities of daily life, such as rising from a chair or climbing stairs. The rate of structural and functional deterioration of muscle appears to vary considerably between people. Part of the variation in the 'rate of muscle ageing' is attributable to genetic factors, the timing of changes in circulating hormones and the presence or absence of chronic low-grade systemic inflammation. Where an individual cannot change much in his or her genetic constitution, circulating hormones and systemic inflammation, (s)he can still significantly slow the rate of muscle ageing by an adequate dietary intake and regular physical activity. Finally, it is suggested that age-related alterations in the capillary bed may negatively affect muscle mass.