Which term refers to a decrease in muscle mass or strength over time?

The term that refers to a decrease in muscle mass or strength over time is atrophy. This condition occurs when muscles are not used regularly, leading to a reduction in muscle size, strength, and function. Various factors can contribute to atrophy, including prolonged inactivity, aging, disease, or malnutrition.

Atrophy can be particularly significant in cases where individuals may be immobilized due to injury or illness, resulting in loss of muscle mass. It is crucial to differentiate atrophy from conditions that involve muscle degeneration—the latter may involve intrinsic disease processes affecting muscle fibers rather than just a reduction in use.

Other terms mentioned relate to different muscle conditions: muscle denervation focuses on the loss of nerve supply to muscles resulting in weakness; myopathy refers to diseases affecting muscle tissue directly, often leading to weakness without a primary focus on muscle mass; and dystrophy specifically involves genetic disorders characterized by progressive muscle degeneration and weakness.