Validity and reliability of a linear positional transducer across commonly practised resistance training exercises

J Sports Sci. 2019 Jan;37(1):67-73. doi: 10.1080/02640414.2018.1482588. Epub 2018 May 31.

Abstract

This study investigated the validity and reliability of the GymAware PowerTool (GPT). Thirteen resistance trained participants completed three visits, consisting of three repetitions of free-weight back squat, bench press, deadlift (80% one repetition maximum), and countermovement jump. Bar displacement, peak and mean velocity, peak and mean force, and jump height were calculated using the GPT, a three-dimensional motion capture system (Motion Analysis Corporation; 150 Hz), and a force plate (Kistler; 1500 Hz). Least products regression were used to compare agreeability between devices. A within-trial one-way ANOVA, typical error (TE; %), and smallest worthwhile change (SWC) were used to assess reliability. Regression analysis resulted in R2 values of >0.85 for all variables excluding deadlift mean velocity (R2 = 0.54-0.69). Significant differences were observed between visits 3-2 for bench press bar displacement (0.395 ± 0.055 m; 0.383 ± 0.053 m), and deadlift bar displacement (0.557 ± 0.034 m; 0.568 ± 0.034 m). No other significant differences were found. Low to moderate TE (0.6-8.8%) were found for all variables, with SWC ranging 1.7-7.4%. The data provides evidence that the GPT can be used to measure kinetic and kinematic outputs, however, care should be taken when monitoring deadlift performance.

Keywords: GymAware; Velocity based training; power; reliability; strength and conditioning.

Publication types

  • Validation Study

MeSH terms

  • Adult
  • Biomechanical Phenomena
  • Humans
  • Reproducibility of Results
  • Resistance Training / instrumentation*
  • Resistance Training / methods
  • Time and Motion Studies
  • Young Adult