EFFECT OF WINDOW LENGTH WHEN SMOOTHING WITH SINGULAR SPECTRUM ANALYSIS TECHNIQUE IN RUNNING DATA

  • Kazuhiro Ishimura
  • Shinji Sakurai
Keywords: smoothing, SSA, running kinematics filter, optimum cutoff frequency

Abstract

The purpose of this study was to demonstrate the effect of window length on running kinematic data in comparison to data smoothed using a digital Butterworth low pass filter. The raw marker trajectories were smoothed using a digital Butterworth filter with an optimum cutoff frequency and using the SSA technique with window lengths of L = n/2, n/5, and n/10 (n = 220). Data smoothing using SSA parameters of L = n/10, r = 2 produced similar results to the Butterworth low pass filter with an optimal cutoff frequency of 13 Hz. In conclusion, a window length of L = n/10 is recommended for running kinematics research, while window lengths of L = n/2 should be avoided.
Section
Coaching and Sports Activities