ACSM Personal Trainer Certification Practice Exam

Which type of muscle injury is characterized by delayed onset muscle soreness (DOMS)?

1. Chronic injury

2. Traumatic injury

3. Acute injury

4. Muscle overuse

The correct answer is: Chronic injury

Delayed onset muscle soreness (DOMS) is primarily associated with muscle overuse, which often occurs after engaging in unfamiliar or intense physical activity, especially when it involves eccentric muscle contractions. This soreness typically occurs 24 to 72 hours post-exercise and is part of the muscle's natural healing process following microtrauma to muscle fibers. In this context, muscle overuse is characterized by the gradual buildup of stress on the muscles, leading to symptoms like soreness, stiffness, and reduced performance. Recognizing DOMS as an outcome of overuse helps differentiate it from injuries that occur from sudden trauma or acute events, which would typically produce immediate pain and may not have the delayed onset characteristic of DOMS. Chronic injuries involve long-term conditions resulting from repetitive strain over time, while acute injuries occur suddenly due to trauma or impact. Therefore, muscle overuse is the key characterization of DOMS, as it indicates that the muscle has been pushed beyond its current strength capacity, leading to delayed soreness as the body repairs and adapts.