Journal of Human Sport and Exercise

Concurrent validity of VmaxPro, Kinovea, and Speedograph for the assessment of peak barbell velocity during the bench press: A comparison of technological approaches and historical evolutions

Authors: Ingo Sandau, Arne Ritterbusch, Adrian Schelenz, Maren Witt

Reliabilty checked
Validity checked
Metrics analyzedMean Concentric Velocity
Products comparedKinovea, Speedograph

Measurement of barbell velocity is a simple and effective way to control strength training. To assess the concurrent validity of different technological approaches measuring barbell velocity, video-analysis (Kinovea), linear velocity transducer (Speedograph), and an inertial measurement unit (VmaxPro (Enode Pro)) were compared. Sixty-eight female and male sport science students lifted two repetitions in the bench press exercise at self-selected barbell loads. Peak vertical barbell velocity (Vmax (Enode Pro)) was parallel measured during the concentric phase of the lift using the aforementioned devices. Concordance correlation coefficient (CCC), Deming regression (DR) and Bland-Altman analysis (BA) were used to assess relative and absolute concurrent validity of Vmax (Enode Pro) measured with Kinovea, Speedograph, and VmaxPro (Enode Pro). Results confirmed high concurrent validity of Speedograph and VmaxPro (Enode Pro). (CCC = 0.99, standard deviation of differences [SDD] = 0.04 m•s-1) without detecting proportional or constant bias. In contrast, Vmax (Enode Pro) measured with Kinovea showed poor concurrent validity to Speedograph (CCC = 0.83) and VmaxPro (Enode Pro) (CCC = 0.81) with significant proportional and constant bias. Regression based re-calibration of Vmax (Enode Pro) from Kinovea resulted in an SDD = 0.09 m•s-1 compared to Speedograph and an SDD = 0.08 m•s-1 compared to VmaxPro (Enode Pro). Among the three tested devices, Vmax (Enode Pro) assessed using Kinovea showed poor concurrent validity. Furthermore, as Kinovea showed proportional bias compared to Speedograph and VmaxPro, application-specific re-calibration of Kinovea should be applied when barbell velocity data is compared to Speedograph and VmaxPro (Enode Pro).

Findings

High concurrent validity with Speedograph (CCC = 0.99). No systematic or proportional bias, indicating excellent agreement.