What is the term for the shrinking of a muscle due to disuse?

The term for the shrinking of a muscle due to disuse is atrophy. Atrophy refers to the reduction in the size or wasting away of an organ or tissue, often as a result of lack of physical activity, immobilization, or aging. When muscles are not regularly engaged in movement or exercise, they decrease in size and strength, leading to functional decline.

In contrast, hypertrophy refers to the increase in muscle size that occurs in response to resistance training and physical activity, highlighting a development process rather than a reduction. Stress typically refers to the physical or emotional strain that can affect overall health and well-being but does not specifically pertain to muscle size. A contracture is an abnormal shortening of muscle fibers, tendons, or other tissues, which can lead to stiffness and limited range of motion but is distinct from muscle shrinkage due to disuse. Therefore, atrophy is the appropriate term for the described condition.