What is the primary cause of DOMS (Delayed Onset Muscle Soreness)?

The primary cause of Delayed Onset Muscle Soreness (DOMS) is micro-tears in muscle fibers that occur primarily as a result of eccentric exercise. Eccentric contractions happen when a muscle lengthens under tension, such as when lowering a weight or running downhill. These actions create tiny tears in the muscle fibers, leading to inflammation and soreness in the affected muscles.

This muscle damage triggers an inflammatory response that contributes to the sensation of soreness experienced 24 to 72 hours after the activity. The body then repairs these micro-tears, which ultimately leads to muscle adaptation and strength increases, though this process initially results in pain and stiffness.

Understanding the connection between eccentric exercise and DOMS is crucial for athletes and fitness enthusiasts as it helps in designing training programs that allow for adequate recovery, while still pushing the limits of strength and endurance. Properly managing the intensity and volume of eccentric exercises can help mitigate the severity of DOMS while enhancing performance over time.