Hi Mark,
thank you very much for your response and for bringing your expertise to the conversation!ย ๐ I got a bit cautious with heart rates because unfortunately I drove myself into overtraining using the MAF-formula and I observed positive drift at a rate of 90bpm already. But you are right, at the moment I am quite slow. If I guess my AeT at 50 s/lap, then 80s/lap would be 50% below my AeT and therefore I might indeed be just seeing a warm-up effect.
Your input inspired me to plan some slow drift tests without warming up to better understand the dynamics of the warm-up phase. At some point the negative drift must come to rest. Maybe I can find out how long it takes me to warm up at certain speeds. It is so exciting to understand and feel your own physiological state. I will keep experimenting and I’ll keep you posted! ๐