I don't know if this is the right section or not... I am new to HR based training and am just starting to watch the data. I just did a 1 hour run with my HR in the "Easy" (zone 2) section for the entire run. I popped up into the "Aerobic" section for a couple very short periods, but probably less than a couple minutes total.
Why at the end of my run when it shows the Training Effect, does it say 3.3 Aerobic and 1.8 Anerobic? If my HR was below zone 4 the entire time, I wouldn't have expected any Anerobic impact.