Abstract
When powerlifters use an oral appliance, their performance may be improved in the international powerlifting competition. The detailed mechanism of the effect of the oral appliance was not clarified. It is necessary to examine the effect on the performance of the barbell movement during powerlifting with an oral appliance. The data from the three-dimensional motion capture system were effective considering reliability and accuracy. However, the measurements of the barbell movement during powerlifting were difficult at the research institute using 3D motion capture, as the heavy barbell was able to go down onto floor. It was important to easily measure the barbell movement in the training room. We used a commercially available accelerometer together with a commercially available eyewear with a three-axis accelerometer, and built an acceleration measuring system which measures physical and barbell acceleration at the same time. The purpose of this study was to evaluate the acceleration measuring system when we measure the physical and barbell acceleration during the deadlift. Accelerometer values were obtained from 10 volunteers（healthy males）performing 3 trials each of a barbell deadlift. The wireless accelerometers were attached to the waist back and the left side of the barbell to measure peak acceleration during the deadlift. The data were analyzed using repeated measures analysis of variance for the head and Friedman test for the waist back and the barbell. There were no statistically significant differences in the peak accelerations（head: p＝0.941, waist back: p＝0.074 and barbell: p＝0.371）among the 3 lifting trials. This acceleration measuring system using multiple acceleration sensors can be a valuable tool to measure the peak acceleration during the deadlift.
