Reliability of a combined biomechanical and surface electromyographical analysis system during dynamic barbell squat exercise

Citation

Brandon R, Howatson G & Hunter A (2011) Reliability of a combined biomechanical and surface electromyographical analysis system during dynamic barbell squat exercise. Journal of Sports Sciences, 29 (13), pp. 1389-1397. https://doi.org/10.1080/02640414.2011.588956

Abstract
An analysis system for barbell weightlifting exercises is proposed to record reliable performance and neuromuscular responses. The system consists of surface electromyography (sEMG) synchronized with electrogoniometry and a barbell position transducer. The purpose of this study was to establish the reliability of the three components of the system. Nine males (age 28.9 ± 4.8 years, mass 85.7 ± 15.1 kg) performed squat exercise at three loads on three separate trial days. A data acquisition and software system processed maximal knee angle (flexion), mean power for the concentric phase of squat exercise, and normalized root mean square of the vastus lateralis. Inter-trial coefficients of variation for each variable were calculated as 5.3%, 7.8%, and 7.5% respectively. In addition, knee joint motion and barbell displacement were significantly related to each other (bar displacement (m) = 1.39-0.0057 × knee angle (degress), with goodness-of-fit value, r 2 = 0.817), suggesting knee goniometry alone can represent the kinematics of a multi-joint squat exercise. The proven reliability of the three components of this system allows for real-time monitoring of resistance exercise using the preferred training methods of athletes, which could be valuable in the understanding of the neuromuscular response of elite strength training methods.

Keywords
Biomechanics; neuromuscular; resistance exercise; strength training; squat exercise

Journal
Journal of Sports Sciences: Volume 29, Issue 13