Concurrent and Predictive Validity of an Exercise-Specific Scale for the Perception of Velocity in the Back Squat

Background: the aim of the study was to develop and validate a specific perception velocity scale for the Back Squat exercise to discriminate the velocity of each repetition during a set. Methods: 31 resistance trained participants completed 3 evaluation sessions, consisting of 3 blinded loads (light, medium, heavy). For each repetition, barbell mean velocity (Vr) was measured with a linear position transducer while perceived velocity (Vp) was reported using the Squat Perception of Velocity (PV) Scale. Results: Pearson correlation coefficients (r) showed very high values for each intensity in the 3 different days (range r = 0.73-0.83) and practically perfect correlation for all loads (range r = 0.97-0.98). The simple linear regression analysis between Vp and Vr revealed values ranging from R2 = 0.53 to R2 = 0.69 in the 3 intensities and values ranging from R2 = 0.95 to R2 = 0.97 considering all loads. The reliability (ICC2.1, SEM) of Vp was tested for light (0.85, 0.03), medium (0.90, 0.03) and heavy loads (0.86, 0.03) and for all loads (0.99, 0.11). The delta score (ds = Vp - Vr) showed higher accuracy of the PV at heavy loads. Conclusions: these results show that the PV Squat Scale is a valid and reliable tool that can be used to accurately quantify exercise intensity.