Final answer:
Muscle wasting or deterioration, known as atrophy, can result from diseases like cancer and AIDS, or as part of aging with sarcopenia, which is often irreversible. Exercise can help offset atrophy effects, except in genetic conditions like Duchenne muscular dystrophy where muscle deterioration progresses steadily.
Step-by-step explanation:
The deterioration of muscle mass or wasting away is referred to as atrophy. There are various conditions that can lead to this deterioration, including diseases like cancer and AIDS, which may induce cachexia—a body wasting syndrome. Muscle atrophy can also be caused by lack of use, certain medical conditions like congestive heart disease, diseases of the liver, and even by natural processes such as aging, which leads to a condition called sarcopenia. While sarcopenia is age-related muscle atrophy that is typically irreversible, other forms of muscle atrophy due to disuse can often be reversed with exercise, which adds structural proteins and causes cellular changes to offset atrophy effects.
Exercise can help maintain muscle mass by producing more cellular mitochondria, increasing capillary density, and enhancing the mass and strength of connective tissue. Unfortunately, people who are sedentary are more susceptible to the impacts of atrophy, including functional impairments such as problems with locomotion, balance, and posture, which can lead to a decreased quality of life and medical issues. Muscular dystrophy, such as Duchenne muscular dystrophy (DMD), represents a specific category of diseases where muscle atrophy progresses due to genetic deficiencies like the lack of dystrophin protein.