RELIABILTY OF ELECTROMAGNETIC TRACKING IN DESCRIBING PITCHING MECHANICS

  • David W Keeley
  • Gretchen D Oliver
  • Christopher P Dougherty
  • Michael R Torry
Keywords: biomechanics, baseball pitching, motion capture

Abstract

The purpose of this study was to establish the reliability of an electromagnetic tracking device (ETD) in analyzing young baseball pitchers. Two data collection sessions in which throwing kinematics were recorded were conducted across a five day span. Joint kinematics were calculated using the International Shoulder Group recommendations. Correlation analyses examining inter-day reliability of the ETD showed that the system was within acceptable limits (r > 0.73). Throughout the selected instances of the pitch cycle, the ETD used in the current study was shown to be reliable across multiple data collection session with ICCs ranging from r = 0.73 to 0.86. It appears so long as the setup, sensor attachment, and digitization protocols remain consistent across data collection sessions, ETD’s are a reliable tool in analyzing throwing movements in younger subjects.