What term describes the condition where muscle fibers increase in size due to exercise?

The condition where muscle fibers increase in size due to exercise is referred to as hypertrophy. This biological process occurs primarily in response to resistance training and various forms of load-bearing exercises. When muscles are exercised, they undergo microscopic damage, which the body repairs by fusing muscle fibers together, resulting in increased mass and strength. This adaptation is a key factor in physical fitness and is essential for athletes and individuals who engage in regular exercise.

In contrast, atrophy describes a decrease in muscle mass and size due to disuse or aging. Recovery refers to the process of healing and regaining strength after exercise, but it does not directly pertain to the increase in muscle size. Contraction is the process by which muscles shorten to produce movement, but it does not imply an increase in muscle fiber size. Therefore, hypertrophy is the term specifically related to the increase in muscle fiber size as a result of exercise.