Taking my AeT as 108 from tests so far…
I usually err on the conservative side and round down to the nearest five. It’s also easier math to calculate other zones and remember them if they have a base of 5.
It also false precision to define a threshold, which is very dynamic, as “161” or “123”. SO I would use 105 as AeT. There’s no downside.
* How should I determine the lower end of zone 1 – another 10% off the AeT?
It’s pretty fudgy, but I usually use 50% of AeT. It’s not really that important though. Anyone who’s training seriously is already motivated to maximize performance, so as soon as the running shoes are on, they’re going to take it right to the line. The upper limit is more important in order to hold us back.
** I get 97 as the top of zone 1 from The Uphill Athlete page for AeT drift test which says subtract 10% from the AeT
Yeah, 10% is the rule of thumb that we use, but in your case I would use 90. ~10 beats is not much of a window. Also, if your new to aerobic training, defining is Z1 is less of an issue. Eventually, with enough multi-year volume, Z2 will become quite fatiguing. That’s when defining Z1 becomes more important.
*** Since we’re talking endurance training, I don’t think I need to be concerned about these
I think it’s worth doing an AnT test though. Because your AeT BPM is lower than average (again, just as a number, not as a performance indicator), it would be good to know how much of a spread you have between AeT HR and AnT HR.
…so would that be small amounts of zone 3 with zone 1 still being the primary percentage of your training time?
It depends on the goal event, but yes, Z3 is the most common intensity at that point.
It’s also worth noting that most people don’t have to worry about that for quite some time. For example, my HR thresholds have been very close for 15 years, largely because of lucky circumstance of a lot of long alpine climbing days from 1999 to 2005. But even after I started structured endurance training in 2014, it took me three years before AeT was too fatiguing for continuous training.
Like you say in the post, it definitely requires a lot of mentally discipline to not train above the AeT in order to build a base!
Yes, but then it can become like meditation. I think of it as “my grocery list pace”. When I’m in Z1 now (which is most of my training), the last thing I think about is intensity. I don’t listen to music or podcasts, so I just zone out, usually thinking about blog posts I want to write.