The use of Loss Velocity and the Rate of Perceived Exertion to Assess Effort Intensity During Sets of Bench Press Exercise Performed until Exhaustion

The objective of the present study was to verify the agreement and correlation between effort intensity determined from the rate of perceived exertion (RPE) and loss velocity in sets performed to exhaustion in the bench press exercise at a self-selected velocity. Thirty-five men and women practitioners of resistance training (33.61 +/- 8.16 years; 172.75 +/- 11.04 cm of stature; 76.79 +/- 15.57 kg of body mass) were evaluated. Participants were familiarized and then performed two sets of bench press performed until exhaustion at a self-selected velocity at 70% and 85% of one-repetition maximum (1RM). Loss velocity was measured by a linear position transducer (Ergonauta (R) encoder) applied to velocity-based training. A 3-point RPE scale was used to evaluate the perceived exertion of the individuals. The analysis of agreement (Kappa test) and correlation (Spearman test) were applied (p<0.05). The results of the study indicated the existence of a moderate degree of agreement (kappa = 0.499; kappa = 0.509 for 70% and 85% of 1RM, respectively), but a strong correlation (rho = 0.720; rho = 0.753 for 70% and 85% of 1RM, respectively) between the effort intensity determined by the Ergonauta and the RPE, at both intensities analyzed (70% and 85% of 1RM). Despite the lack of perfect agreement between methods, loss velocity and RPE seem to demonstrate strong consistency, allowing both to be used for controlling intensity in resistance training. The results of this study should be interpreted in light of individual characteristics, type of exercise, and training objectives.