Validity and reliability of Gyko Sport for the measurement of barbell velocity on the bench-press exercise

BACKGROUND: The aim of this study was to examine the validity and reliability of the novel inertial measurement unit (named: Gyko Sport) for the measurement of barbell concentric velocity on the bench-press exercise. METHODS: Ten under-16 (U16) basketball players performed 2 repetitions of the bench press exercise with 6 different loads (40, 50, 60, 70, 80 and 90% of one repetition maximum [1-RM]; N.=120 repetitions). Mean velocity for each repetition was simultaneously recorded using the Gyko Sport and SmartCoach linear transducer. RESULTS: Results showed a very large correlation between the SmartCoach and Gyko Sport (-0.79; standard error of estimate [SEE] 0.18 m/s). Furthermore, there was a very high agreement between both devices for the measurement of the mean velocity (intraclass correlation coefficient [ICC]-0.774; Cronbach's alpha [alpha]=0.872; Bland-Altman Plots [R-2]-0.070). The Gyko Sport registered similar, but slightly higher values than the SmartCoach (P=0.103; mean difference 0.075 +/- 0.05 m/s). CONCLUSIONS: The results support the use of the Gyko Sport as an affordable, portable, and suitable wearable device to measure mean velocity on bench press exercise.