Delayed-onset muscle soreness does not reflect the magnitude of eccentric exercise-induced muscle damage

This study investigated the relationship between delayed-onset muscle soreness and other indicators of muscle damage following eccentric exercise. Male students (n = 110) performed 12 (12ECC), 24 (24ECC), or 60 maximal eccentric actions of the elbow flexors (60ECC). Maximal isometric force, relaxed and flexed elbow joint angles, upper arm circumference, and plasma creatine kinase activity were assessed immediately before and after, and for 4 days after exercise. Muscle soreness (SOR) was evaluated by a visual analog scale (a 50-mm line, 0: no pain, 50: extremely painful) when the elbow flexors were palpated (SOR-Pal), flexed (SOR-Flx) and stretched (SOR-Ext). Although 24ECC and 60ECC resulted in significantly (P <; 0.05) larger changes in all indicators and slower recovery compared to 12ECC, no significant differences were evident for SOR-Pal and SOR-Flx between 12ECC and 24ECC, or 12ECC and 60ECC. In contrast, SOR-Ext was significantly (P <; 0.05) lower for 12ECC compared to 24ECC and 60ECC. A Pearson product-moment correlation showed SOR-Pal did not correlate significantly with any indicators, however, SOR-Ext and SOR-Flx showed weak (r <; 0.32) but significant (P <; 0.05) correlations with other indicators. Because of generally poor correlations between DOMS and other indicators, we conclude that use of DOMS is a poor reflector of eccentric exercise-induced muscle damage and inflammation, and changes in indirect markers of muscle damage and inflammation are not necessarily accompanied with DOMS.