Polarized Training Deep Dive and TrainerRoad’s Training Plans – Ask a Cycling Coach 299

I love how engaged the TR team are and it is this that sets it apart from other training platforms. Half way through this pod. Its great listening. Thank you all.


I think the “hard” or “easy” characterisation should be more related to the impact the session has on the endocrine system. I need to document myself, and here I am basing the next hypothesis on my feelings,so I might be completely wrong: but the SS sessions, although feeling much easier than a 4x8mn by Seiler, might have some similar impact on the endocrine system. I feel that the cumulative 1 hour SS workouts 3x a week before the real “difficult WO” are having a real toll and when I come to the real challenging workout (threshold; OU; VO2max), I am mentally drained and bail out quickly in the 3rd or 4th week of the plan in those WO. Maybe swapping one or 2 SS WO by z2 rides would help to recover better, at least mentally, before tackling the breakthrough WO

A bit OT: I also wanted to thank the TR team to let everybody discuss the topic openly. I am following the different threads, without participating because things are sometimes hot enough. Also, being opened to implement the polarized plans even if the team believes their approach is better is something everybody should applause. So thank you.

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I was struck by the small sample size of most of these studies, n<20 in most cases. Not sure any of them have p<.05 statistical significance.

And then thinking about the mountain of real world data TrainerRoad is sitting on and the studies that could be generated from that…it would amazing to see a collaboration between TR and academic exercise physiologists/data scientists.


It can’t be as binary or simple as sessions v TiZ surely?

Must be both or else you can also come up with extreme examples of why sessions 80/20 is a nonsense too, eg. 2 hard sessions a week, 4 hours long with constant intervals & 4 easy sessions a week, 30 mins Z1.

Clearly polarised in terms of sessions, but it’s absolutely daft.

We need clarity and ratios to work with. We need to know why riders are being told not to do Z1 after intervals on the hard days (several forum users here say this, yet high end athletes and pros do it) to not increase time in zone 1.

What exactly is the data they’re referring to that shows this is detrimental.

What are the sessions
What is the TiZ
How much Z1 fatigue is allowed after hard intervals without damaging ability to perform next hard workout (or should this be done pre intervals, or some before, some after - and what is the evidence comparing all of these).

I think any really POL training plan will address and monitor these, especially one like AT. Athletes need progression and Z1 progression, as is being suggested in some camps, ends up being 2x5 hour rides in Z1 at the weekend. Not sure that suits everyone, though they may be able to fit some in on hard days.


Can you quote an example, can’t remember seeing this?

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Yes if I can find the thread where I was asking about adding Z1 to my interval days and guys were saying hard day hard, easy days easy. Can’t see it at the moment but spotted these in my replies, kinda on the same theme. Are you suggested that the consensus is actually that adding Z1 to increase TiZ in POL is a good thing judging by your surprise there?

Also when I asked recently about adding Z1 to intervals to make up the TiZ to 80/20

Yes. Doing the test immediately after the block of training, when one block had significantly more volume, almost certainly impacts the immediate test results. Seems like an awfully obvious thing to overlook, tbh.


I posted this somewhere previously (maybe above) but this is the final outcome of a three week block where I was doing 2 vo2 workouts a week and the rest z2, it was 2 hard workouts to 6 z2 workouts. But the fact that people can’t really agree on a standard for this, whether it’s TIZ or ratio of sessions just makes me believe that this isn’t the magic formula so many think it is. I’m sure some of the busybodies around here will say my hard workouts weren’t hard enough or I shouldn’t have been doing z2 after a workout, or not enough z2 on the weekend. lol

No one is saying don’t add Z1 to the end. We are saying that adding Z1 to the end doesn’t make the plan Polarized, capital P.

Has Seiler specifically stated a definition of POL and has Seiler said that 80/20 TiZ isn’t as effective or isn’t POL?

I don’t think there is an official Seiler POL plan anyway. So how can we know what’s a POL plan and what isn’t.

I think magic spanner is OK, useless spanner might be construed as being negative.

I just listened to a podcast with Seiler talking. His 80/20 was initially referring to workout ratio ie not TiZ. But at the same time he was saying “taking TiZ it could even be 90/10” in both cases he was talking about what pro-athletes are typically training. More important and characteristic for pol is to spend almost no time in Z2.

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I have seen LOTS of discussion on the 80/20 tracking, and this is what I gathered from those early podcasts 3+ years ago. It’s entirely possible I understood wrong, or the actual method is different now, but here is what I understood:

Session Time for the 80% / 20% Distribution:

  • Percentage refers to Total Session Time with the Goal at the intended Zone Intensity (Z1 or Z3).

    • This is called “Session Goal Based Intensity Zone Distribution”.
  • Look at the entire workout length, the Goal Intensity Zone for that workout (Z1 or Z3).

    • That entire workout time is the “Session Time”.

    • It is NOT specific minutes of time spent in each of the three training zones during a workout.

    • It is NOT the simple 1, 2, 3 count of total number workouts. You must consider the Total Session Time for the percentages.


Right it’s not clearly defined. There’s a few issues here and they mean we can’t determine a simple plan based on sessions alone.

One you mentioned, some athletes were 90/10 (like the XC’ers), and then we had others doing 78% Z1.

So there’s no 80% there. Problem again is that this time spent in the zones - actual TiZ. That’s what was measured - in hours.

From that you can roughly take 80/20 TiZ or 90/10 TiZ (not all these athletes within their groups were training exactly the same either).

Then on top of that you can throw in sessions. If Seiler’s saying 80%, well then good luck working out 80% weekly of your days on the bike because the ‘2 hard days per week’ guys are talking about is 33% of your 6 day week session time.

That’s a contradiction. So you have to extend it and plan further out to make it 80/20. Monthly, Yearly etc. Then you have rest weeks to factor in when you span it out.

Clearly TiZ is important, maybe even more important than sessions I’m thinking, yet the fixation right now is on sessions and the comments are around sessions per week.


At the end of the day, I think it comes down to the age-old advice “make your easy days easy and your hard days hard”. Something I remember reading (but still often ignoring) years ago from Joe Friel (Joe Friel's Blog: Easy Means Easy) who was just passing on learnings from long before that. Hard days could be VO2 Max work but could also be Threshold/Sweet Spot intervals depending on target events and training period etc.

I think the difficulty comes in defining “easy”, which could actually be sweet spot for those with a very strong aerobic system or much lower for others. Self-limiting power when HR/breathing is indicating that you’re moving out of your aerobic zone (even if going relatively slow) is tough to do though.

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People can argue the definition of polarized however they like, but the thing that started all this was people asking for Polarized plans, meaning four days Z1 and one or two days Z3. All this other talk of including Z2 or mixing zones in workouts is just a distraction from what is generally defined as a Polarized plan and what people were asking for.

If you want to tack Z1 work onto the end of rides to add time in saddle or tss, that’s great, but it’s not what people were requesting.


I still don’t see how we get to 4 days Z1 and 2 days Z3 from the 80/20 sessions ‘rule’ guys are taking about. That’s 67/33.

Surely it’s TiZ that’s easier to work with - makes it simple to create an 80/20 plan.

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Thanks for taking the time for digging those out. I think its a bit of a misunderstanding or interpretation of what the message is or was intended to be.

In those examples I more read it more as don’t just add Z1 time to the end of a Z3 session to balance the TiZ closer to 80/20 (80/20 is a bit of a myth as well but lets not go there.)
Its not saying dont add Z1 but suggesting how to categorise the session.
Personally agree you should add Z1 but not cut the session up as in 20% was intervals 80% was Z1. If you do Z3 in a session and add Z1 it is still a Z3 for the purpose of POL.

That is not the same as saying dont add any Z1 in a Z3 session.

A slight simplification but true…
Z1 + Z3 = Z3 session
Z3 + Z1 = Z3 session
Z1 + Z2 = Z2 session
Z2 + Z1 = Z2 session
Z1 only = Z1 session

Yes I know the studies use the Polarised Index / time in zone but generally that is not how people train or setup their training.

I think of it this way say I do Z3 6x 5 minute rest 5m VO2max intervals adding on an hour of Z1 is 2 hours but the hour of Z1 doesn’t balance or undo the stress of the VO2max work in fact it adds to it. Spliting out the session of an hour Z3 and saying ah well I did an hour of low stress Z1 work (after the VO2 work an hour of Z1 isnt easy), I’ll count that the same as an hour of standalone Z1 makes no sense.


Nice post. Everything in a nutshell :clap:

I dont agree TiZ is easier or you can split sessions up. I have stated my reasoning two posts up, hope it makes?

And POL doesnt equal 80/20 that is a myth. It might, it is a popular distubution, but it doesnt have to be, it could be 66/33, 90/10 95/5 etc