Final answer:
Delayed onset muscle soreness (DOMS) is associated with microscopic tears in muscle fibers and a resultant inflammatory response, not with lactic acid buildup, depletion of muscle glycogen, or immediate muscle cramps.
Step-by-step explanation:
Delayed onset muscle soreness (DOMS) is most likely due to microscopic tears in the muscle fibers that occur during exercise, particularly when the muscles are engaged in an activity that is more intense than they are used to. The damage to muscle fibers results in an inflammatory response that causes the discomfort felt as DOMS. This tearing also leads to a release of calcium from the sarcoplasmic reticulum (SR), which can contribute to cellular damage and muscle fiber degradation. Although lactic acid build-up can cause immediate stiffness and fatigue during and right after exercise, it disperses fairly quickly and thus is not the primary cause of DOMS, which appears much later and lasts longer. Similarly, the depletion of muscle glycogen and ATP reserves are factors associated with muscle fatigue during exercise but are not directly responsible for the delayed soreness experienced.