Originally Posted by Harold74

A lot of folks here have mentioned RPE and and the conversation test. I want to explain why I feel that those metrics are likely less valid for me than they are for "normal" people without type two diabetes.

San Millan discusses the phenomenon by which it is common for diabetics to have collapsed zone twos. I think that's likely true of me. I have to maintain a very low level of exertion to be able be in zone two based on heat rate and I suspect that glycolytic energy production dominates throughout nearly all phases of my workouts unless I'm very deliberate about keeping my exertion levels low.

Consider some of my metrics:

1) My ramp test FTP comes in around 220 watts.
2) I suspect that my real FTP is closer to 150 watts, if I even have an FTP in any meaningful sense.
3) My zone two power output seems to be a paltry 135 watts which will shift to 115 wats over the course of a 90 min ride, presumably due to cardiac drift.
4) I can keep talking and breathing at levels of exertion that are much higher than my zone two power output based on heart rate.