Recently I’ve been looking at different ways of visualising physiological data, and have created a Poincare plot of a funfair ride at Southport PleasureLand I sampled last year. This form of visualisation plots current and successive heartbeats as x, y coordinates, so if a subject’s heartbeat was successively 70, 80 and 75 beats per minute (bpm) we would plot (70,80) and (80, 75) on an X-Y graph. In the instance below I’m plotting heartbeat activity as inter-beat interval which is the time between beats rather than the beats per minute. I’m particularly fond of Poincare plots as its easy to grasp a subject’s heart rate variability from casual inspection. At rest a subject’s heart rate variability should be high, and so individual beats should be spread out over the graph in somewhat of a noisily fashion. When stress is applied heart rate variability decreases and beats cluster.
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