Carbonfiberboy 

IOW, if one had a workout which specified it was to be performed at 90% of FTP and, lacking a power meter, one did it at 90% of LTHR, would that be the same? Assuming good nutrition and hydration, etc.

RR3

I do not know the answer but will share my experience.

I have a power meter on my bike and also one on my trainer. I have a lactate measuring device. Assuming good nutrition and good cooling (huge factor). I am a little too lazy this morning to dig up the data but I would say output is directly linear until you get to LT2 and then weird stuff happens because at somepoint you are going fully anaerobic. My heart rate will actuallly drop 5-8 beats even though my blood lactate and power output is up. This happens at about 4.6 mmol/L for me.

I think LT2 and FTP are the same. LT2 is defined as 4mmol/L lactate and is basically the Maximum Lactate Steady State that you can handle. Last time I did a test, my LT2 was about 290 watts at 152 BPM HR on the trainer (probably more like 260 on my G3 Powertap....not sure which is more accurate but I don't care). From about 150 Watts until around 250, I remember the relationship to be linear.....HR and power that is.

N = 1

YMMW

Drew Eckhardt 

It's linear between AeT and AnT which is the basis of the Conconi Test

From Training Lactate Pulse-Rate by Peter Janssen:


No because the zero intercept is different. At 0% of FTP you're at your standing resting heart rate. The numbers also don't seem to match for me when I look at fraction of heart rate reserve presumably due to crossing AeT.

If you don't have power and heart rate data from a long matching steady-state effort you could interpolate from Friel's power and heart rate zones, like the zone 3 / 4 split at 90% of FTP and 94% of LTHR. 95% of FTP is 5 / (100% - 90%) halfway to it and should be 94 + .5 * (100-94) = 97% of LTHR.

Carbonfiberboy 

Thanks. I understand about the zero intercept. My question was too simplistic, but thanks for answering what I meant. I am only interested in the area between VT1 and VT2. I've never seen a HR anomaly around VT2. The higher my HR, the faster I go. Anybody else who uses both HRM and PM?