[todd.struble]

I have been training for a few years now and I’m having trouble curing ADS or at least interpreting my gains in fitness. I’ve found over the last year of training, when doing my DIY AeT outdoor tests via the 5% Pa:Hr metric, my AeT heartrate is plateauing at around a 15% spread between my AeT and AnT. However, despite my AeT plateauing, I have gotten much faster at the same AeT heartrate, close to 1:40 min/mile faster in the last 6 months. 90% of my volume over this time has been at Z1 or Z2 measured by that AeT mark according to Training Peaks. The other 10% has generally been a speed workout about 3 times a month (Z3 volume)

I’ve tried to keep the language generalized since individual numbers are probably not super helpful but here are the taglines from the tests I saved in Training Peaks:

4/23/21 AeT DIY Outdoor Test HR 155/Pace: 9:10 Pa:Hr 2.33%
8/15/21 AnT Time Trial 1 hr: 185 bpm
10/10/21 AeT DIY Outdoor Test HR 155/Pace: 7:33 Pa:Hr 4.5%

My main question is… am I on the right track or am I still not doing enough Z1/Z2 volume despite the increases in pace? Is the 10% volume in Z3 a problem? Listening to the podcast and reading some of Maffetone’s work, I am definitely improving in terms of pace at the same low-intensity heartrate, which seems to be his measure of aerobic improvement, but maybe there’s nuance there I’m missing that the 10% test is exposing? I’ve read here the prescription for ADS is most or all of your work in Z2, but I’d also say that my Z2 pace is now creating fatigue that is more difficult to recover from, and I can only increase my Z1 volume so much (without risking injury).

Topic

[Reed]

Reed on October 13, 2021 at 6:08 pm #58032

You’ve improved your AeT pace from 9:10 min/mi to 7:33 min/mi over six months? That seems pretty great! Seems like you’re definitely on the right track. I’m curious what your average weekly volume is, and what that’s looked like over the past couple of years. You might also find that there are now other opportunities for improvement that weren’t as visible before, such as strength training, stability, mobility…

I’d suggest that the “prescription for ADS” is more along the lines of “spend plenty of time below (and well below) your aerobic threshold.” If you’re trying to keep your mileage steady or increasing, but now you’re running all of it at a 7:30/mi pace, that might be hard. You’ll still get plenty of benefit both as a stimulus to improve your aerobic capacity as well as an aid to your day-to-day recovery by doing a bunch of easy 9:00/mi miles (or slower!).

[Anonymous]

Anonymous on October 14, 2021 at 8:21 am #58061

Hi todd.struble,

If the goal is to move the AeT needle, shouldn’t Z3 work be dropped? To my understanding, if Z3 intensity recruits faster twitch muscles, it results in a different metabolic stress than Z2 effort, potentially inhibiting aerobic/oxidative capacity (though upregulating anaerobic/glycolytic capacity).

More modulation may be needed if you’re not recovering well. Aerobic workouts should be repeatable the next day.

[todd.struble]

todd.struble on October 14, 2021 at 2:32 pm #58087

I was trying to avoid the details and more thinking about the general idea of pace @ AeT improving and how it relates to the ten percent test! But if it helps, I’m 39m, about 3 years since I first cracked open TFTNA. The first season I trained about 400 hours using a very extended version of the 24 week mountaineering plan here. When I started I was very aerobically deficient. My AeT was 140 bpm and 11:00 min/miles. 400 hours was a bit too much with foot problems popping up at the end of the season. After that we had our first child so my volume has been similar if not a bit less with parenting duties and a family illness taking time from training.

Recently I’ve worked with a non-UA coach (my wife’s triathlon coach! Kind of like the Carolyn Parker husband-and-wife client podcast except the other way around) towards improving my flat and downhill running speed because that is where I get dropped in my trail running races. I’m at about 25 miles a week of running plus about two hours of zwift riding, mainly to avoid the foot issues which has worked well for me.

With respect to dropping that much time of my AeT pace: 1) I think in the April test I could have gone a bit faster – I note the decoupling was very low with the 9:10 min/mile pace; so perhaps if I were more diligent I would have tested again in that same period at a higher pace/heartrate; and 2) I was actually very surprised by my latest test, which prompted me to post here. I was very much expecting a higher heartrate at a different pace before I started the workout. My plan was to test closer to a 165 heartrate and what I thought was going to be something like 8:30 min/miles or so. Instead, as I finished my warmup I was comfortably nose-breathing at the ~7:30 pace, but felt right at the edge of the “all-day” pace in terms of speed. My watch said 155 bpm. So instead of pushing it, I just stayed at the same pace and figured we’d see if I could keep the heartrate steady for the full hour, and I got the 4.5% Pa:Hr result.

I suspect I improved significantly in my running economy due to spending more time on flat routes and the speed workouts, which I’m thrilled about. But I suppose I’m wondering if @Eddie is right and my AeT HR is stagnating because of even 10% Z3 volume. Or alternatively, is this result in the realm of AeT being a moving target with fatigue and stress and maybe I should just test again on a different day?

Also re: Aerobic workouts being repeatable the next day – I think it’s also noted that as one’s Z2 pace gets faster, it becomes difficult to recover from the efforts (and pounding!) and more Z1 volume is necessary. About half of my aerobic volume is Z1/recovery pace according to Training Peaks.

[Anonymous]

Anonymous on October 15, 2021 at 9:48 am #58139

Ideally, tests are performed with identical conditions, and as you mentioned, AeT is a variable to control – it’s not a static number and may change daily depending on recovery.

Doesn’t AeT and the 10% rule simply provide a framework for training and not an end to itself? If your performance is improving, that’s what really matters, right?

There is a wealth of information in the forum archives and worth taking a deep dive. Have you read the following? They touch on similar topics with excellent replies from Scott J.:

(I’m unable to post links, so see the attached txt file.)

[Anonymous]

Anonymous on October 19, 2021 at 10:30 am #58285

Hi Todd,

Is your AeT/AnT percent change in pace within 10%? Given your AeT pace is improving and not your HR, perhaps pace may be the better metric for intensity than HR.