Sunday, April 24, 2011
Cross Training: Heart Rate Creep
I brought along my Polar 725 HRM and transmitter this last Saturday for a familiar run on Euclid Avenue in Upland, CA. My friends and I have been doing this since I started running in the late 1980's. On Saturday I ran up to the fire station on 24th from our start on 17th. That's 1.75 miles up. Then I ran back. I felt good so I ran down to 16th and back to 17th twice to add another mile. (The blocks are conveniently 1/4 mile each.) My total: 4.5 miles.
I made it a point to back off if my rate went over 140 going up. I'd walk until it came down to about 120 and would start again. I was pleased that the "creep" in heart rate was modest. See the sawteeth just before the peak. Many's the time in the past my rate hit about 180 here. My time up to the fire station was a little under 27 minutes, close to 15 minutes/mile or 4 miles/hour. Not bad for an old guy going uphill. My time back was a little over 19 minutes, about 9 min/mile or a little over 6 miles/hour. Both segments included walking to bring HR within the 120-140 range. I rested only 3 minutes at the top, 2 minutes at the bottom, and 5 minutes at the end. My average excluding these rests was almost exactly 4.5 miles/hour. Include them and the average is about 4 mph. Notice that there is some cardiac "creep" at the end and that my heart rate going downhill was greater than going uphill! (124 versus 139). And I had trouble keeping my rate in the targeted range. I think this fact has to do with training and would be true whether or not I was going downhill. But the fact that I was going downhill reaveals the creep more explicitly. If I went on a 10K training regime, I would expect to see less creep on the second half on this run as I built up my miles.
The 5 minute rest at the end shows the drop in heart rate which is good in the first minute dropping from 160 to 130, but it required another couple of minutes to get to 100. Still okay, I think.
Not shown here is the most recent OwnIndex of 40, equivalent to an O2Max without the hassles of actually doing an O2Max test. Excellent for my age, so they say. I'm glad I took my Polar along with me. Cross training occasioned a cross-check on my cardio, and it could be a lot worse.
This helps me with my conjecture about the best when to get to Pasadena from Claremont on foot. It's a walk/run combo like Euclid.