I’ve got lots of stats on my blog, and one of the posts with the most number of hits is my page on the Modified Conconi Test that I did. Interestingly, there’s still little good information on this, and I still think Ross’s Maximum Performance for Cyclists is still the best book out there for explaining this process. The tricky thing is finding the deflection point after reviewing the data.
Here’s my HR data. Note that the first deflection point is supposed to be the aerobic threshold and the second is the lactate threshold. Ignore the 4th point, I was messing with the bike which reduced my watts and heart rate.
Then the cadence data; the first bend in the graph can help you identify the aerobic threshold if the above heart rate graph doesn’t help. Around point 10, I started messing with the shifting to maintain my power, thus the changes in cadence.
And finally the critical power data; when the curve starts to change slope, that’s another pinpoint for lactate threshold. This is the graph I’m hanging my hat on for my heart rate zones.
Deflection points in these graphs indicate both the lactate threshold rate and the aerobic threshold rate. However, finding those points is the tricky part.
Here are the heart rate zones I ended up selecting, which are far different (within the zones at least) than my original HR data.
Interestingly, my maximum heart rate hasn’t changed much. It’s zones 2 – 4 that have really been tweaked, and I can definitely tell. Training in the initial zones was been brutal for me. Enough that I readjusted to the final zones (by interpreting the deflection points differently and paying more attention to the critical power graph). The final zones do feel right…when riding in my prevous HR zones (higher than the 2007 numbers, by the way), it seemed like I was always in zone 4 and easily spiked to zone 5. Now when I’m training, I’m generally in zone 3 and 4, and spikes into zone 5 when doing intervals or hitting a steep hill.
Now that I’m into the high intensity intervals, heart rate doesn’t really matter that much since watts are now my guide, but the HR zones will be important for when I’m riding without the power meter and only have HR as my general guide.