Well, folks, no sooner had I said that I'd never done 400s or 800s than I went out for a run with the Calgary Road Runners and we did -- 6 x 800s. It was great fun! I did feel like I was going to puke, but I pulled back just enough to stave that off.
When I got home and plugged in my Garmin, I got a heck of a surprise though. Yes, this was the fastest I have worked this year. That's all well and good. The overall pace was about race pace for me. My average overall heart rate was 155, which is lower than what I race at. I usually sustain an average heart rate of about 163 for over two hours in a half marathon, with a maximum HR around 181. Is that normal for a 37-year old?
I'm asking because tonight my maximum heart rate varied from 182 to... get this: 226. WTF???
Twice before I've clocked a max HR at 255, but I assumed the Garmin malfunctioned for a second or two. But tonight I saw the max HR change for each interval and for three of the six intervals, it maxed out over 200 - once at 200, once at 202 and once at 226. I backed off a bit for the last three and maxed out in the 180s.
My resting HR, from what I can figure, is about 59 or so. My blood pressure is generally on the low side of normal... 111/70 or so is about average for me. I had my annual physical in May and I'm fit as a fiddle. And I feel great - especially since I finished off the Accutane earlier this month.
So, running friends, what do you think? Was it a Garmin malfunction? Should I try again next week and see if it continues? Should I go to the doctor, go directly to the doctor, not pass Go and not collect $200?