Changes in maximal voluntary contraction torque and rate of torque development after initial and secondary bouts of maximal knee extensor eccentric exercise

A bout of eccentric exercise confers protective effect against muscle damage after the same exercise performed several weeks later, which is known as the repeated bout effect (RBE). We investigated whether the RBE magnitude would be different between maximal voluntary contraction (MVC) torque and rate of torque development (RTD). Fourteen young men performed 100 eccentric knee extensions twice separated by 4 weeks. Knee extensor MVC torque and RTD were measured before and 24-72 hours after each exercise. The magnitudes of MVC torque and RTD reductions were similar after each bout, but it was significantly smaller after the second than the first bout. The greater the decreases in MVC torque and RTD after the first bout, the greater the RBE. It was concluded that MVC torque and RTD changed similarly after eccentric exercise, and the their magnitude of decreases after the first bout was associated the magnitude of RBE.