Final answer:
Sarcopenia is the term for the loss of muscle mass and strength that occurs with age, which exercise can help delay but not entirely prevent.
Step-by-step explanation:
The loss of muscle mass and strength that naturally occurs with age is referred to as sarcopenia. This is a biological process where there is a gradual decrease in the ability to maintain skeletal muscle mass, affecting individuals in later adulthood. The exact cause of sarcopenia is not definitively known, but it is believed to involve a reduction in sensitivity to growth factors necessary for muscle maintenance. Noteworthy diseases like cancer and AIDS can cause muscle atrophy, but sarcopenia is a specific age-related condition. Notably, exercise can help delay the onset of sarcopenia, by adding structural proteins to muscles and causing cellular changes that can offset muscle atrophy.