Yesterday was hard leg day again but I changed it up a bit. It was challenging but interesting. Previously I summarized the proper pace for long easy endurance sessions as: “make sure you pass the talk test”. I still stand by that, but there are fancier ways to get an accurate upper limit for this pace. One is proposed by Coach Joe Friel, for determining your lactate threshold pace: go hard for 30 minutes, then measure your average heart rate over the last 20, and multiply by about 0.85. This pace is another estimate of the upper end of your aerobic zone, which you should not exceed for long endurance training.
So I did this test today, standing up pedaling against the wind. Owwee! That was tough. Here is my HR for the last 20 minutes of the ride:
Polar Beat gave average HR 133. So the upper range for my aerobic zone, which I use for my easy pace, should no more than 0.85 times that, or 113. Now here’s the fun part. Dr. Phil Maffetone is the most famous proponent of doing a lot of training in this lower intensity range to develop your aerobic system. He has a very simple formula for estimating this number: 180 – your age. He says that over the years, working with a lot of elite athletes, this formula has always worked well, compared to more sophisticated tests. I’ve always been a bit skeptical of that, knowing that the simple formula for max heart rate, 220-age, is not accurate for me. But 180 – my age of 68 is: 112. So I could have saved myself the discomfort of the test and just trusted Dr. Maffetone. Or I could have just gone by the talk test. Yesterday, for example, I cruised for a 2 hour plus comfortable pace and my average HR was: 113. But I’m actually glad I did the test (just this once!) to settle any doubts in my mind.