Hi,

I’m new here. I’m transferring from road to longer trail running and I’m trying to figure out my AeT. I currently can’t get on a treadmill due to lockdown 2 here and it’s kinda hilly round here, so I know it’s never going to be perfect, however my estimates seem a little high and I wanted to know if they make sense.

Initially, I was using nose breathing to give me a rough estimate. I maintained a nose breathing pace for around an hour after warming up. My average heart rate was 160.

That seemed a little high to me, so I started looking at HR drift data for several runs done at nose-breathing pace as well. I hadn’t set out to use these runs for drift testing so they aren’t ideal, but I think they are telling me I am in the right ballpark. However, this still seems a lot higher than most people report.

I have attached three examples. They are mostly a little short after trimming off the warm up and parts where I slowed down for other reasons (bad footing). Any input would be appreciated.

For some background, I am a 40 year old female. I suspect most of my previous training (for road 10km and half marathons) has been too fast, however I also cycle to work and spend a lot of time hiking in the mountains so I probably get a reasonable volume of aerobic zone work that way. Resting HR is ~53, max is ~189. I don’t have a recent lactate threshold, but a guestimate from my last half is ~172.