Is the EnodePro^® a Valid Tool to Determine the Bar Velocity in the Bench Press and Barbell Back Squat? A Comparative...

In recent years, the EnodePro^® device has been one of the most frequently used velocity sensors to track the bar velocity in resistance training, with the aim of providing load-velocity profiles. However, recent articles highlight a lack of reliability and validity in the estimated maximal strength, which can cause a serious health risk due to the overestimation of the bar velocity. With this study, we aimed to investigate whether imprecision in the measurement could explain the variance in this measurement error.

The research question was evaluated by comparing the integrated velocities from the EnodePro^® with the velocities from a high-resolution displacement sensor for the squat and bench press. The velocity was measured with loads corresponding to 30%, 50%, and 70% of the one-repetition maximum (1RM) in moderately trained participants (n = 53, f = 16, m = 37). Intraclass correlation coefficients (ICC) for agreement were supplemented by an exploration of the systematic bias and the random error (mean absolute error (MAE), mean absolute percentage error (MAPE)).

The results indicated movement specificity, with the ICC values for the squat ranging from 0.204 to 0.991 and with ICC = 0.678-0.991 for the bench press. Systematically higher velocities were reported by the EnodePro^® sensor (p < 0.001-0.176), with an MAE = 0.036-0.198 m/s, which corresponds to an MAPE of 4.09-42.15%.

The EnodePro^® seems to provide overly high velocities, which could result in the previously reported overestimation of the 1RM. Despite the validity problems of force/load-velocity profiles, we suggest evaluating the bar velocity with accurate measurement devices, which is, contrary to previous reports, not the case with the EnodePro^®.