Reliability and Validity of the Repetition-Counting Feature of the Push Band 2.0 at Different Repetition Speeds

Abstract

Purpose: To assess the interdevice reliability and validity of the repetition-counting feature of the Push Band 2.0. Methods: Thirty college-aged participants (aged 18–24 years) simultaneously wore two Push Band 2.0 devices and performed 10 common resistance training exercises at four different tempos over the course of two testing sessions. Twelve repetitions were completed with visual confirmation for each set of exercises and compared with repetition estimates from the Push Band 2.0. Interdevice reliability was quantified using single measures intraclass correlation coefficients with 95% confidence intervals while validity was assessed via mean absolute percent error and mean percent error. Results: Interdevice reliability was found to be good to very good regardless of exercise type or tempo, as all intraclass correlation coefficients were >.770. Validity of the repetition-counting feature of the device was dependent on both exercise type and tempo, as exercises that did not involve rotation of the device throughout the movement demonstrated greater mean absolute percent error (31.0% average of all four tempos) and mean percent error (−29.9% average of all four tempos) than those that required such rotation (average mean absolute percent error of 3.5% and mean percent error of −1.6% across all four tempos). Conclusions: This study supports the reliability of the repetition-counting feature of the Push Band 2.0. However, device accuracy appears to be dependent on the type of movement and the speed at which the movement is performed, with greater accuracy observed during faster exercise tempos and exercises involving rotation of the device during movement execution.