Fig. 9
From: Identification of animal movement patterns using tri-axial magnetometry
a TriMag data collected from a human front crawl swimmer in a sea-race (a back mounted tag attached with tape, sampling at 40Â Hz). b The isolated m-prints for six double-arm strokes of the front crawl swim. The cases were separated using a Fast Fourier Transformation, FFT (yellow waveform) on the x-axis of the TriMag data (pink waveform). There is high consistency evident in the trajectory of points between the six cases, which for competitive swimmers is a measure of efficiency as they are not expected to show great variance across strokes although some of the observed differences may be due to the effects of wave chop