Tuesday, March 16, 2010

Tracking progress

My favorite running gadget (my Garmin 405) lets me record speed and heart rate during a run. I went to the track and ran one lap at (roughly) each heart rate from 105 beats/min up to 160 in steps of 5 beats/min. I call this a "calibration run".

[Update: the laps are all run with no rest between, and the HR is averaged over each lap, I do a 2 mile warmup run at a slow pace and a 2 mile warm down after]

Next, I wrote some software to read in my Garmin data and do a best fit line to it.. turns out that running pace vs heart rate is very linear (unless you running paces very very close to your max HR).

Below you can see this data from March 7th. The 'slope' is the beats/per/minute/per/min/mile. i.e. to speed up one minute per mile, I need to run with a heart rate that is 11.82 beats/min faster.

The table that follows then shows this data for each 1/2 min/mile pace that I might attempt to run. It also shows the percent of my 'working heart rate' that each pace is. My resting HR is 48 beats/min and my max HR is 168 (measured on treadmill at Dr's office) so I have a 120 beat/min WHR.

The cool thing about this technology is that you can actually measure your improvement WITHOUT RACING. You don't even have to run fast on the track (I do just for completeness and better fitting of the data), you can run at a bunch of slow paces (say 12 to 10 minute miles) and then week by week
see your improvement.

I plan to do a calibration run every few weeks during my current mileage buildup...stay tuned to see if I get any improvements!

Slope -11.82, Intercept 231.26, weight 170.6 lbs, temp 60 F, no wind

Here's the graph of the data.

05:00 172.2 103.5
05:30 166.2 98.5
06:00 160.3 93.6
06:30 154.4 88.7
07:00 148.5 83.8
07:30 142.6 78.8
08:00 136.7 73.9
08:30 130.8 69.0
09:00 124.9 64.1
09:30 119.0 59.1
10:00 113.1 54.2
10:30 107.1 49.3
11:00 101.2 44.4
11:30 95.3 39.4
12:00 89.4 34.5
12:30 83.5 29.6


  1. Interesting.

    Is that HR at the end of a lap? Are you resting between laps?

    How do you do this calibration?

  2. The HR is the average over the lap. I run the laps straight through and punch my split button to mark the exact .25
    mile (the GPS has about 4% noise that makes .25 ->.26 miles so I don't use that data).

    When I dump the data to Garmin I get a csv
    file that shows the splits and I massage that to make a table (and graphs etc that don't show up on blog very well)


  3. this is a very interesting concept - never seen something like this before. I might have to try this sometime, it likely would be useful for me to see what it shows.

    Have fun in Denmark, good luck on the marathon!


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