I don’t know myself at all OR Why I bought a Heart Rate Monitor

In our last episode, our intrepid heroine undertook to set her heart rate zones based on a Rate of Perceived Exertion Test. Said test was demonstrably wrong. Because I am absolute crap at working out to RPE. The next day I replaced my scheduled tempo run with a 30 minute treadmill time trial.

The Procedure:  Warm up for 5-10 minutes, run for 30 minutes at best effort, cool down for 5-10 minutes. Take average of heart rate for the last 20 minutes of the effort.

Best Effort? The fastest pace that you can maintain for the time period. Your best effort for one minute is way different than your best for an hour. There is some fun stuff you can do with testing at various durations and charting the result, but that’s for another day we’re running here!

I set the treadmill at 10 minutes per mile. This is fast for me, for 30 minutes. I have run that fast exactly once in my life. It was a 3.5 mile race about 5 years ago. I had a friend pacing me and I ran absolutely on the red line the whole damn race. I was so close to that line that by the last mile if I started talking I would get nauseous. I kept it up and averaged 9:58 per mile. I nearly vomited at the end of the race. Good times!

That’s the level of effort you’re looking for in a time trial, slow enough to make it the whole way at the same pace, fast enough that you could not go another minute at the end. So it will feel easy at the beginning “Should I go faster? I think I could go faster.” Just right in the middle “Alright, this is good. I’m working but I’m not hurting.” Like death at the end “Dear god let it end. I can do it, just another minute, just another minute.”

For reference, see Jens Voight’s Hour Record attempt. (You watched that, right? It was amazing!!)

I had picked a pace that I knew would be hard but that I hoped I could maintain. This was good! I think I could have actually gone faster but it was absolutely work to finish it.  I made it the whole way and had a bit of gas in the tank at the end. Not a lot though, so the pacing was pretty good.

Now our previous test had given me a Lactate Threshold of 147 beats per minute. I knew this to be false because my predicted max heart rate of 157 was nowhere near the 164 I averaged on my weekend run the previous Sunday.

The new test, the harder test, gave me a Lactate Threshold Heart Rate (let’s just say LT) of 178 beats per minute. Dope. Absolutely. Looks good!

I took that out for a spin the next day. It was an easy day with drills and strides. My goal was to keep my run “Easy” or Zone 2 or lower. As I suspected, my heart rate monitor slowed me down, far below my usual speed for my easy days. I was running outside and it was getting on to 80 degrees. Higher heat = higher heart rate so my easy run pace is slower in the noon day sun than when I’m getting my miles in on the treadmill. At the enforced slow pace I felt great. I didn’t have to take walk breaks to finish the run and today I feel great. I could have kept up that Zone 2 shuffle for hours.

Next week we’ll see where it puts me when I do my 400 meter intervals at 5k +~30 seconds per mile pace. I’ll go with the rate I’ve been using and see where my hear rate goes. Then I will adjust to get my heart where it needs to get the most out of my training time.

-fh