Objective Accuracy in Estimating Repetitions in Reserve in the Back Squat : An Analysis between Experienced vs. Novice Subjects

Abstract

This study aimed to objectively compare the accuracy of estimating repetitions in reserve (RIR) in the back squat among subjects with different levels of experience in resistance training (RT). Sixteen healthy adults (24.31 ± 4.94 years, 4 women and 12 men) were divided into the experienced (N = 8; ≥ 18 months of experience) and the novice (N = 8; <18 months of experience) in RT. Each group performed one set to muscle failure (day 1), and one RIR3 and RIR1 (day 2) of Smith machine back squats with a load of 70% 1RM. In addition, mean propulsive velocity (MPV) and the rating of perceived exertion (RPE; 0–10 scale) were assessed to individually objectify the RIR. There were no differences in accuracy for estimating both RIR3 and RIR1 between groups (p > 0.05, d ≥ 0.03). Furthermore, there were no differences in MPV, velocity loss, the RPE, and total of repetitions to muscle failure, RIR3, and RIR1 sets (p > 0.05, d ≥ −0.07). Overall, our findings suggest that RT experience does not influence the accuracy of estimating RIRs in the back squat, which is objectively supported by individualized MPV and the RPE. Previous familiarity with high-level effort may play a key role in accuracy beyond RT experience.