Validity and reliability of the Myotest Pro wireless accelerometer in squat jumps

Abstract

BACKGROUND: Portable and cost-effective accelerometers can yield instantaneous results of force, power, and velocity, with minimum set-up time to assess muscle power. However, such devices must also produce both valid and reliable data.

OBJECTIVE: The current study assessed the validity and reliability of the Myotest Pro wireless accelerometer (ACC).

METHODS: Thirty physically active males performed two squat jump, on two separate sessions. The jump was recorded simultaneously by a force platform and ACC, which was attached to a barbell resting on the subjects' shoulders. Validity was determined using Pearson correlation coefficient (r) and t-test between the maximum force platform(F $_{FP}$ ) and ACC (F $_{ACC}$ ) force. Between session reliability of F $_{ACC}$ , power(P $_{ACC}$ ) and velocity (V $_{ACC}$ ) from the ACC were assessed with t-test, intraclass correlation coefficient (ICC), and coefficient of variation (CV).

RESULTS: F $_{ACC}$ correlated highly to F $_{FP}$ (r=0.815, p< 0.05), but there was a proportionate ratio bias of 0.81. There was no difference between sessions (p> 0.05) for any variable. High ICCs were found for all variables(F $_{ACC}$ 0.90; P $_{ACC}$ 0.80; V $_{ACC}$ 0.84). Low CV was found for F $_{ACC}$ (2.1%), P $_{ACC}$ (3.3%) and V $_{ACC}$ (3.2%).

CONCLUSIONS: ACC is a valid and reliable tool to use for assessing barbell movement, but caution in power data interpretation is needed.