The Reliability, Bias, Differences, and Agreement Between Velocity Measurement Devices During the Hang Clean Pull

Kissick, CR, Techmanski, BS, Comfort, P, and Suchomel, TJ. The reliability, bias, differences, and agreement between velocity measurement devices during the hang clean pull. J Strength Cond Res 39(3): 289-294, 2025-This study examined the reliability, bias, differences, and agreement between the GymAware PowerTool (GA) and Tendo Power Analyzer (TENDO) during the hang clean pull (HCP). Fourteen resistance-trained men performed HCP repetitions with 20, 40, 60, 80, 100, 120, and 140% of their 1 repetition maximum hang power clean (1RM HPC) with GA and TENDO devices attached to the barbell. Least-products regression was used to examine instances of proportional and fixed bias for mean barbell velocity (MBV) and peak barbell velocity (PBV) between devices. In addition, Hedge's g effect sizes were calculated to determine the magnitude of the differences between devices. Excellent reliability was displayed by the GA for all measurements. While excellent reliability for the TENDO was displayed for MBV across all loads, only moderate-good reliability was present for PBV at loads >80% 1RM. The TENDO displayed proportional bias for both MBV and PBV as well as fixed bias for PBV at 140% 1RM compared with the GA. Despite the small effect sizes that existed between devices for both MBV ( g = 0.35-0.57) and PBV ( g = 0.23-0.54), none of these differences were practically meaningful. The GA and TENDO are reliable devices that can measure MBV and PBV accurately during the HCP; however, practitioners should note that the TENDO may overestimate MBV and PBV to a small extent (3.7-6.8% and 1.8-2.9%).