(16) COMPARISON BETWEEN LOAD-VELOCITY ESTIMATED ONE-REPETITION MAXIMUM AND ACTUAL ONE-REPETITION MAXIMUM DURING THE HANG POWER CLEAN

Purpose: The purpose of this study was to compare the estimated one repetition maximum hang power clean (1RM HPC) from two different linear position transducers and the actual 1RM. Methods: 12 resistance-trained men (age = 25.0 ± 4.5 years, height = 176.1± 7.9 cm, body mass = 90.6 ± 17.0 kg, relative 1RM HPC = 1.3 ± 0.2 kg/kg) completed a single testing session in which they completed a 1RM HPC test with two linear position transducers (Tendo Power Analyzer [TENDO] and GymAware Powertool [GA]) attached to the same sleeve of the barbell. Following a standardized warm-up, the subjects completed a HPC specific warm-up that included 5 repetitions at 30%, 5 repetitions at 50%, 3 repetitions at 70%, and 1 repetition at 90% of the subjects’ self-estimated 1RM. Subjects then performed 1RM attempts until their maximal load was found. The TENDO and GA devices were used to measure mean (MBV) and peak barbell velocity (PBV) of each warm-up repetition and 1RM attempt. After the 1RM was achieved, individual load-velocity profiles were created, and linear regression equations (y = mx+b) were used to estimate the 1RM HPC using the average MBV and PBV produced during each warm-up set for each device. A one-way repeated measures ANOVA was used to examine differences between the MBV and PBV estimated 1RM for each device and the actual 1RM achieved. Hedge’s effect sizes were calculated to determine the magnitude of differences between estimated and actual 1RM. Results: The estimated and actual 1RM descriptive data are displayed in Table 1. There was a significant difference between the estimated and actual 1RM HPC values (p = 0.013); however, post hoc analysis showed no significant differences between the values (p > 0.05). There were moderate differences between MBV estimations and actual 1RM (TENDO MBV vs. 1RM: g = 0.89, GA MBV vs. 1RM: g = 1.06) and small differences for PBV estimations and actual 1RM (TENDO PBV vs. 1RM: g = 0.53, GA PBV vs. 1RM: g = 0.56). Conclusions: There were no statistical differences between estimated 1RM from two different linear position transducers and actual 1RM during the HPC; however, moderate and small effect sizes were present between measurements, respectively. The greatest variation in 1RM was displayed by both linear position transducers within the MBV estimations although PBV estimations also displayed greater variation compared to the actual 1RM. Practical Applications: Strength and conditioning practitioners should exercise caution when using MBV and PBV load-velocity profiles generated from linear position transducers to estimate the 1RM HPC in resistance-trained men as considerable variation may prevent accurate load assessment and prescription as well as the ability to monitor maximal strength progression. Acknowledgements: None.