FTHR Test #2

I put myself thru another FTHR on Saturday. It was pretty grueling, but I survived. However, during the 20 minute session of self-torture (the test portion anyway), when compared to the one I did on Feb 13, I managed to increase my average watts by 21; distance traveled increased by .34 miles; but AHR only went up by 1. What's that mean? It means I put out a little more power and traveled a little bit further during the same amount of time, but for about the same effort as the last time I tested. Another way to look at it is that I would have went from point A to point a B slightly faster. That's the goal, right? On the other hand, this was only FTHR number two so the changes from one to the next could be due to other factors. Will see how the next one goes in about a month.