ERK MAP Kinase Pathway Activity After Heavy Resistance Exercise

This study evaluated a single session of heavy resistance exercise on the activity of the ERK MAPK pathway. Seven males performed 3 sets of 8–10 repetitions at 75%–80% 1‐RM on the squat, leg press, and leg extension exercises (REX) while four served as a control (CON). Muscle biopsies were obtained 30 min pre‐exercise (30MPRE), 30 min post‐exercise (30MPST), and at 6 hr post‐exercise (6HPST). Total and phosporylated levels of MEK1 and ERK 1/2 were determined with ELISA and total and phosphorylated Raf‐1 determined with immunoblotting. Data were analyzed with two‐way repeated measures ANOVA (p < 0.05). No significant changes were noted for CON. However, when compared to pre‐exercise, REX underwent increases in Raf‐1, MEK 1, and ERK 1/2 activation at 30MPST (p < .05) that were also greater than CON. A single session of heavy resistance exercise increases the activity of the ERK MAPK pathway extending from Raf‐1 to ERK 1/2.