Notes
AIM Z3/4 Int (3/1) for 32 mins
Struggled to get into z3 (top of z2...around 153-4 for first couple of cycles.
Struggled to get into z4 at all (got to 162 initially increasing to 165 on the last cycle).
Have my zones shifted???
Anyhow, z4 or not, I was running hard, uphill & building up lactic acid as I couldn't even manage > 50 secs on some of the z4 intervaly. So, I guess I was working hard enough.
I was jogging quite slowly on the z3 intervals, but especially in last 4 cycles, managed to keep just inside z3