Delayed onset muscle soreness (DOMS) commonly occurs after strenuous or unaccustomed physical activity. Traditionally, DOMS was thought to be caused by the accumulation of lactic acid. However, this theory has lost support since the timing of peak lactic acid levels does not align with the onset of soreness and stiffness.
Nearly 120 years ago, researchers proposed that DOMS resulted from structural damage within skeletal muscle. While microscopic changes are indeed observed following intense exercise, more recent interpretations suggest these alterations may reflect a natural remodeling process rather than direct muscle damage.
Growing evidence now points to the fascia, the connective tissue surrounding muscles, a key contributor to post-exercise discomfort. Fascia is a honeycomb-like network of collagenous tubes, richly innervated with sensory receptors. In fact, the density of nerve fibers in fascia is approximately three times higher than in muscle tissue, indicating its significant role in both proprioception and pain perception.
One promising approach to addressing fascial-related discomfort is foam rolling. This technique appears to reduce pain sensitivity and enhance the sliding capacity between fascial layers. Improved intra-fascial sliding likely explains the reduction in soft tissue pain following foam rolling sessions.
