Originally Posted by Grasschopper
Yea no chance your LT is 143bpm. My Max is a few bpm lower than yours and I can maintain in the mid 160bpm for a long time (largely did it yesterday for nearly an hour, I need to train differently). I would guess your LT is more like 167bpm +/- 3bpm or so.
+1.
Do a 1 hour TT all out and take 100% of the average, or 2 20 minute efforts and 95% of the average, or 2, 8 minute efforts and 92% of the average, and that will be your FTP HR, which is about your LTHR.
For me the 2x8 times 92%, worked out virtually identical to my lab measured LTHR. ( Which made me decide to not bother with the lab test anymore.)