fatigued?

sounds like you just need to go off your RPE for a bit and slow down. forget the zones and do what your body tells you to do.

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80/20 Endurance Ambassador

Curious as to your age. I typically feel just as you describe and at those same HR ranges.

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David
* Ironman for Life! (Blog) * IM Everyday Hero Video * Daggett Shuler Law *
Disclaimer: I have personal and professional relationships with many athletes, vendors, and organizations in the triathlon world.

Z2 isn’t hard aerobically for me, but sometimes it’s hard from a musculoskeletal perspective. If I’m not careful, my form changes with slower running to the point of being inefficient.

I have steered away from zone 2 running. In particular by heart rate, I feel that it becomes more of a moderate effort than truly easy.

Try this calculator by Tinman Elite coach Tom Schwartz. His "easy" pace guideline is at least 2 mins per mile slower than what you could run for a 5k today. https://runfastcoach.com/calc2/index.php

Yes, I have definitely felt like Zone 2 is tough! I do 80/20 training, and it's quite a difference when a run workout calls for just Zone 1 vs a short warmup in Zone 1 and then predominantly Zone 2.

This sounds right.

I'm a bike person, I should run slower than I do. But I'm stupid. Either way, my true Zone 2 pace is so slow that even on only like 4mi/wk I can pretty much go run a 1/2 marathon at Zone 2 pace and feel fine. Probably start getting bored.

I had to test this theory the other week when I dropped my car key half way out on a 10k at lunch and didn't notice till I got back. Hence my forum topic about that on here recently! Facepalm, idiot, moron I was.

I learned how to run a low Z2 pace that second 10k!!!!

Yeah, that's def slower,although I still come in at "easy Tempo" pace which sounds about right for upper z2 HR using that chart.

I love running at "easy" pace of 9:00+/mile, but I don't get to run many of those miles on the 80/20 plan! (Granted, it also has you running less than 30mpw for most plans, so something has to give - I ran LOTS of 9-11 min/miles when I was marathon training at 70mpw. LOTS!)

Side topic, but is there a zone system that everyone considers "standard" when throwing out zones? This is the 2nd thread I just read where a zone is specified without the context of a system. Is Coggan 7-zone implied unless otherwise stated?

Yeah, there is a variation in what is considered Z2, which is why I mentioned the 80/20 plan, as that's what I'm using and is popular.

https://www.8020endurance.com/8020-zone-calculator/

I've found they are mostly similar though, although yes you will have variations at the hi-end of Z2 between plans.

Something is off here and I think it’s your expectations. You say zone 2 is (1) mildly annoying; (2) you aren’t huffing and puffing; (3) you run this pace for 1.5-2 hours regularly; and (4) you could (albeit, barely) handle a conversation. All that sounds about right except the conclusion you draw that it all
equates to a surprisingly hard run. Putting aside the fact that any run will be “harder” if you do it for 2 hours, I don’t think anyone of us consider a long run that has the above characteristics to be a “hard” pace. The part about inability to listen also seems way off to me but that’s personal as I can listen to music in any zone. Personally, as another poster said my legs get fatigued if it’s longer but I don’t find the pacing the least bit taxing from a HR perspective.

Its really really hard for me to run in Zone 2, but its more mental than physical. It just feels so slow that it drives me crazy.

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"see the world as it is not as you want it to be"

What can I say, that's how I feel with Z2. Maybe I'm just a wuss when it comes to Z2 running!

Note I'm not saying it's an objectively HARD run. Its' not - I do plenty of Z3-Z4 and even Z5 stuff, and its a lot harder, for sure.

Still, I'd be lying to say it's all easy street for me at Z2. When that 80/20 plan calls for 90 minutes at Z2, even though aerobically I'm not dying, I'm going hard enough that it's would be seriously annoying if someone was running and was expecting to be all chatty. And as said, I can't even do audiobooks at high z2 - that gets annoying too, while at Z1, I love listening to audiobooks, even for 2 hrs.

But as said, I'm pretty sure it's a 'real' Z2 for me, given that I run it weekly without a megabeatdown, and for sure I don't get into Z3-5 which I also know from doing that later in the week (those line up as well correctly HR wise).

For sure though, it's very clear to me that I would obviously get faster by doing a lot of volume at this pace, especially given the pace picks up as I get more fit. I'm not sure I'd say I feel that way with Z1, where you really wonder if you are improving with all those Z1 miles. (I still feel strongly those Z1 miles are a critical base for long stuff for marathon training, though. Not as much so for Oly triathlons given you're likely running <30mpw.)

Ah, gotcha. I wasn't even aware that "80/20" was a site. I'll check it out.

But of course they have to define Yet Another Zone System. :)

I literally NEVER feel that way (anymore).

I do come from a pure running background though, so I've never really run slower than the equivalent of training for a 20:xx 5k for the past 25 years, so it's probably not too surprising.

Similarly, my lack of swim background as well as my super limited swim training time absolutely leads to atrociously slow Z2 HR times in the pool. Like really sad.

Here is the 80/20 zone calculator:

https://www.8020endurance.com/8020-zone-calculator/

Running in Zone 2 is easy. If it isnt for you, then you´re doing something wrong.

ditch the heart rate monitor and just run by feel

Just knocked my numbers into this and Zone 2 on there ranges from a steady pace to very easy for me, I tend to follow the Jack Daniels running paces.

Currently increasing my miles, taking the covid break as a reason to do a running block, I've averaged 10mpw for the last couple of years and so far this year ive worked myself up to 30mpw all on a diet of easy/steady paced runs depending on how the legs are feeling on the day. But I wouldnt run them all steady which would be the top end of this 80/20 zone 2 because i wouldn't recover (220lbs runner).

I find HR and breathing not to be an issue and the majority of the time they feel great, but you do get days where you are fatigued and 'easy' pace doesnt feel easy muscularly and you cant wait for it to be over... but I mean it certainly doesnt feel tough like a 5k/10k/tempo kind of pace where you are breathing harder and having to work for it, the pace is still easy to hit.

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@the.lazy.triathlete

https://www.strava.com/athletes/18691068

That's exactly what happens to me. Per heart rate if I stay in my true Z2 (zones based off track testing) then I find I have a hard time keeping my form and cadence where it feels comfortable and I end up hurting from it as in pain, not effort. My run becomes almost a shuffle and it gets ugly. I've found if per my HR I'm more high Z2/low Z3 I can keep the cadence and form that feels good and let's me build. It's a slow build and it's a process but it's kept me more injury free and given better results.

Is this zone 2 in a Seiler 3 zone system or zone 2 in a 5 zone system?

5 zone system

As a non-runner, former swimmer and 48y old it took me three years to finally being able to call Z2 easy. My zones are determined in pace/power terms using lactate threshold and ventilatory tests which I do through my club at least every three months so they should be fairly accurate.

What kept me at feeling comfortable while running Z2 was not a cardiovascular cap/effect or substrate usage (which are things determined by LT / breathing gas tests) it was / is related to purely to muscular endurance (for lack of better terms). So while I was easily able to keep a conversation my legs just hurt after 90min of Z2. I think, what solved it for me was consistent strength training. Low volume (so 3-4 times approx. 30min) but consistent. Luckily I got barbell and a couple of kettlebells prior to the whole pandemic thing blowing up so these 30mins of training cause an effort of maybe 35-40min which is totally manageable.

At 2 hours of running in zone 2 you are supposed to be fairly fatigued by the end of it

But you also shouldn't need to be doing anything extra to maintain focus on the pace.

Ignoring heart rate for a second how does this pace compare to your PR's? the way you describe it makes it sound like you may be close to your marathon pace/effort, is that correct?

Doing 2 hours at marathon pace weekly is a big ask and you would probably benefit from slowing it down by 10-20 seconds per mile. it should still line up with zone 2 heart rate but also not be overly strenuous

My Z2 run pace in min/mile lines up roughly with the Mcmillan calculator results if I plug in a 19:30 5k (I'm likely faster than that, my last 5k was 18:50 but that was in race shape), it gives me a wide range of 7:20-8:35/mi for 'easy RPE2-4' efforts.

Honestly, I'd peg the RPEs of my Z2 runs at 4-5 in high z2, 3-4 in low z2, but definitely not 6 or up. So even though it's 'surprisingly hard' for me, it's not like I'm really pushing hard.

It's entirely possible I'm running my 2 hr runs at near 'marathon pace' given my current fitness (on only <30mp) but I seem to be recovering fine and not limited (thanks to the reasonable 80/20 plan.)

That said, the range of Z2 varies a lot for pace and HR, so I definitely take advantage of it - I will run low z2 or even high z1 if I'm feeling a bit beat down, and take it up to hi z2 if I'm feeling pretty good.

I'm doing the 80/20 Oly Advanced plan right now, and it doesn't get you much more than 30mpw runinng, so I'm not surprised that I feel like I'm running overall faster than I did when I was doing pure marathon training at 70mpw and doing a LOT of z1 work. Z2 feels a lot harder than Z1 for me (even though I wouldn't call z2 a 'hard' effort!)

As others have noted your heart rate seems low for the Z2 effort you are putting out. I would agree that maybe try running more by feel rather than pace since you are so aerobically fit. Slow your run down by maybe 30-40 seconds per mile and ignore your heart rate and see how it goes.

My N=1: I recently ran a 18:39 5K (48yo) so my Z2 according to that calculator is 8:12 - 9:23. I am currently running 6 days a week between 50-60 mph mostly in the upper part of that pace range. I am very comfortable in the 8:45-9:20 range for around 2 hours (13 miles or so). At that pace I can definitely talk to someone. Once I go beyond that duration my pace drops because my feet/legs are really feeling the pounding (and possibly because I am not generally fueling at all). In that pace range I can keep my heart rate in the 135-145 range though that it is really very temperature dependent and when hot out I might be 10-15 beats per min faster or if it is cooler out I can run 10-15 seconds faster with the same effort. Anyway when I do mid-range runs (8-10 miles) at the lower end of my Z2 it certainly is more difficult and I wouldn't be able to carry full conversations with anyone I was running with. I suspect dropping into the higher range of your Z2 would make your runs more comfortable and still provide the necessary training stimuli.