Saturday I had twelve kilometres to run and I wasn't really in the mood to run at 7+ minutes per kilometre just to keep my heart rate in the 70-75% zone that I was supposed to stay in. Instead, I decided to run at whatever pace felt right and then analyze my heart rate afterwards to see if I could learn anything from it.
The route I chose was an out and back - literally. I ran down one road for six kilometres, turned around and ran all the way back. The way out was into the wind and (with a sigh of relief) the wind pushed me all the way home.
Does anyone want to guess what happened?
On the way out (into the wind) my average pace was 10 to 15 seconds per kilometre slower than it was on the way back. My heart rate on the way out was about 5 beats per minute faster than on the way back home.
So I ran more slowly with a faster heart on the way out and ran faster with a slower heart rate on the way home.
I now know that numbers - what to do with them?
My thinking is that, if I were racing today, I would have looked at my watch on the second half of the run and, even though my pace was faster, I would have realized I wasn't working as hard as I was working before and I would have pushed myself to speed up until my heart rate reflected the effort I wanted to have.
I guess what I'm going to need to figure out is what heart rate reflects an effort level that I can sustain on a long run. On Saturday I had an average heart rate of 161 and a max of 168. If I followed the rules of 70-75%, I should have stayed between 146-152 but the rate I ran at was comfortable, didn't feel too difficult and left me with lots of energy for the entire run. Could I have run a half marathon at that rate?
I think so.
Could I run it at a faster rate than that? I don't know but the research I did tells me that I should run a half marathon at 166-170 which might be possible.
I have 10 more weeks of training and heart rate experimentation to find out.
By the way, did I mention I booked my ticket for Tel Aviv? Woohoo!