What happens to your max heart rate during the #TourDeFrance? For @efprocycling, data shows a consistent decrease in time spent in the max HR zone — aka zone 5 —over the course of the race so far. Riders went hard during Stage 4 thanks to a rest day and spent an average of 24 minutes in zone 5. However, that steadily declined in Stage 11 to an average of just under 4 minutes, due to accumulated fatigue, changing altitude and self control. We’re ready to see what the back half of the race brings. #UnlockYourself