Validity and reliability of a 3-axis accelerometer for measuring weightlifting movements

The purpose of the current study was to assess the validity and reliability of measures obtained by a 3-axis commercial accelerometer during weightlifting movements in comparison with kinematic data derived from the 3D videography. Kinematic data from 3D videography were obtained from 11 track & field throwers performing 3 trials each one at different loads in power snatch, power clean and jerk from the rack. The results showed that the accelerometer measures were highly correlated with derived acceleration data from 3D videography data in the vertical plane (Z axis) taking up to the pull phase (including first pull, transition and second pull) for power snatch and power clean and up to the highest point of the bar path before the catch position (including dip, drive and split phases) for jerk from the rack. On the basis of these results, this device was proven to be valid and reliable on Z axis on the weightlifting movements studied. Thus, this system may be a useful and easy to handle tool to measure acceleration during real-time training sessions.