Thursday, December 10, 2009

Heart rate, schmeart rate

I am not happy to report that a satisfactory maximum heart rate value continues to elude me, but not for a lack of trying.  My workout during the Run to Feed the Hungry was a first attempt to find the magic number.  While I attained a high value (192 bpm) within the first 1/2 mile of the race, I wasn't able to get my heart rate up high enough at any later point in the race to satisfy my coach and me that I had hit a max value.  My heart rate actually declined throughout the race and was 174 bpm at the finish.

Tuesday, I took another shot at this during a tough workout.  Here's what I did:
  • 2 mile warm up
  • 15 minutes @ LT effort (ave. 6:00 pace; ave. HR 171 bpm)
  • 3 minute jog
  • 5 x 75 second hills @ 3k effort
  • 5 minute jog
  • 12 minutes @ LT effort (ave. 6:07 pace into headwind; ave. HR 170 bpm)
  • 3 minute cut-down from 3k to mile effort (Max HR 177 bpm)
I was to record my maximum heart rate during the workout and it was 178 bpm (attained while climbing a hill during the first 15-minute LT effort interval).  This is not my max.  I know it's at least 181 bpm since I hit that HR multiple times during the Run to Feed the Hungry race/workout but never felt like I was "maxing out".

I decided to consult the internets to find another way to determine my max.  I found this very thorough discussion by Sally Edwards where she offers a number of formulas (mostly unreliable), HR max tests as well as submax tests.  I decided I'd try the step test.  It consists of stepping up and down on an 8" step for 3 minutes using a slow but steady cadence and recording your average heart rate during the last minute of the test.  You then add 75 (if you have excellent fitness) to that number to get your max.  My HR averaged 107 bpm during the last minute of the test giving me a max. of 182 bpm.  I don't think this a reliable value.

At this point, I'm a bit fed up with the quest to determine my max HR.  I proposed to my coach that I could just use my HR at LT effort to determine my max, but she pointed out that my LT effort heart rate may actually be quite close to my max.  I guess that's why I'm not sure it makes sense to spend much more time trying to figure it out.  If I were to go with a max of 182, then I should be running LT effort at an average HR between 160-167 (88-92% of max a la J. Daniels).  Based on my recent workouts, I'm pretty sure that LT effort has me between 170-175 bpm and marathon effort/pace around 162-169 bpm.  It seems like guessing at a max value is just going to complicate the issue.

I do feel like I gained some useful insight if nothing else from this quest.  I looked back at my workouts from 2007, where I actually spent a lot of time running with my HRM strapped to my chest.  I was able to see evidence of distinct progress as well as validation of my marathon effort and LT effort heart rates.  Back before I ran my first sub-3 hour marathon in April 2007, I did my last long run with 14 miles at goal pace (average pace 6:40-6:55) and happened to wear my HRM.  My average heart rate during the goal pace part of the workout was in the 168-171 bpm range.  This is close to, albeit slightly higher than, the heart rate range for my marathon-paced workouts right before Twin Cities.  However, 2 years later, I was averaging 30+ seconds per mile faster.  Progress!

The bottom line for me is that I'm going to wear my HRM more often and not just during easy workouts to keep myself slow.  I want more data.  My hope is that someday I will see a max value that I can use.  If nothing else, I'll have data to geek out on 2 years from now where I can (hopefully) reminisce on how much faster I am running while maintaining an average heart rate of168 bpm.  


  1. Way too geeky for me. :-) More numbers than my college physics textbook. Jack Daniels would be proud, but I don't have time to analyze, just run.

  2. Can't you just go and get tested at one of those centers where they put you on a treadmill/stationary bike and check all sorts of stuff, like maxHR, VO2max, LT, etc. ?

  3. I don't run by HR. I think about trying it every once in a while, but never do, including because I don't want to have to figure out my MHR.

    Daniels is not big on HR training because of day-to-day variables. Hence his use of pace. Here's a recent article from the Times on it being an hour-to-hour thing: Ready to Exercise? Check Your Watch .

  4. Kris-duffer, I am a geek through and through and don't really want to "just run". It's not nearly as fun for me without all of the accompanying analysis.

    Bozot, I did get my VO2max tested a few years back. I wasn't able to get a true max reading back then either because I was afraid of flying off the back of the treadmill. My HR was continuing to climb when I jumped off.

    Joe, I prefer using pace too, but that can cause problems for my effort-based workouts. My training paces necessarily become faster as I progress in a training cycle. It's always hard (psychologically) for me to start off at a slower pace at the beginning of a cycle than what I was running at the end of the last. It would be nice to correlate effort, pace and heart rate in a way that allows me to train at the right pace/effort for the conditions (time of day, temp., stress level). I see a multivariate analysis in my future:)

  5. You need to be 'rested' (or at least not have done a hard or long session the previous day) to find your HR max.

    What works fairly well for me is a 3k race (time trial for you?) at maximum effort and with a sprint finish (over the last 2-300m or so). Sprinting to the finish is important. I got 166 for that recently, and I've been calling my max 167, so pretty close.

    You could be mid-180s if you weren't maxing out in that race.