Click on the photo above to watch the video.
At the same time look at the graph below. It shows TJ's heart rate and heart rate variability (low when stressed) in real time. The timing on the graph and the video are the same so you can see what makes TJ stressed and what helps him relax.
HRV is in purple and HR is in black. Time is shown along the bottom of the graph so that you can compare the levels with the activity.