Which term describes loss of fitness due to reduced training?

• A. Detraining
• B. Duration
• C. Frequency
• D. Variety

Answer: (A)

Detraining describes what happens when you reduce or stop training: the body's adaptations to regular exercise begin to fade as the training stimulus is removed. Because many fitness gains are reversible, stepping back from training leads to a decline in fitness levels. In endurance, VO2 max and stroke volume can decrease quickly; at the muscular level, mitochondrial density and oxidative enzymes decline, and strength also falls with disuse, though often more slowly due to neural adaptations. This term best captures the loss of fitness caused by reducing training. The other terms refer to how training is scheduled—duration is how long a workout lasts, frequency is how often you train, and variety is mixing different exercises to target different systems—rather than describing the decline that follows reduced training.