Association of MMP3 gene polymorphism and sex on recovery of muscle strength after eccentric exercise

Abstract

Individual differences in muscle strength recovery after eccentric exercise may be influenced by sex and genotype. A candidate genetic polymorphism associated with response during muscle recovery is the MMP3 gene rs522616 polymorphism, encoding matrix metalloproteinase (MMP-3). Here, we investigated the effect of the MMP3 gene rs522616 polymorphism and sex on muscle strength recovery after eccentric exercise. A total of 95 healthy subjects (50 men and 45 women) performed 5 sets of 6 maximal eccentric elbow flexion exercises. Maximal voluntary contraction torque (MVC), range of motion (ROM), and muscle soreness, as well as blood parameters (creatine kinase [CK] and interleukin-6 [IL-6]), were assessed immediately before and after and 1, 2, 3, and 5 days after eccentric exercise. No significant time × group interaction in MVC torque after exercise was observed between groups in both sexes. Furthermore, the study revealed sex differences in the area under the curves (AUC) of CK and IL-6, where the AUC values for both CK and IL-6 were higher in men compared to women. A significant genotype-sex interaction was identified in the recovery of MVC, calculated by subtracting the MVC immediately after exercise from the MVC on day 5 after eccentric exercise. The G allele showed a significantly lower recovery of MVC than the AA genotype in men. However, no significant differences were observed in women. This study demonstrated the interaction between the MMP3 rs522616 polymorphism and sex in muscle strength recovery after eccentric exercise.