Mapping 7 Zone to 3 Zone Model Wrt Polarized Training

[Coach_Ron]

Hello,

Just trying to get my head around Intervals.ICU classifications of training intensity distributions in the 7 zones (such as for Polarized or Pyramidal training) and how it compares with the classic 3-zone session duration used in most literature that describe such training schemes.

I’ve seen there’s a link to an FFT Youtube video but I’m curious if there’s a better reference to see how the mapping is done from a 7-zone model to a reference 3-zone mode (outside of general shapes of bar distributions). Maybe a spreadsheet of some sort to verify/cross-check what’s going on?

Just as a refresher, below table is how Polarized training is classically described. Here, the % time is the % of total session time spent in each of the zones. Going by this :

• 75-80% session time is suggested in Z1 in a 3-zone “low intensity” area. It appears this would map to Z1, Z2 and a tad bit of the lower end of Z3 in a 7-zone model.
• 15-20% session time is suggested in Z3 in a 3-zone “high intensity” area. It appears this would map to an area top end of Z4 and beyond in a 7 zone model.
• 0-10% session time is suggested in Z2 in a 3-zone “moderate intensity” area. This would map to a small area between top end of Z3 to lower end of Z4 in a 7 zone model.

Appreciate it if someone can confirm this is how Intervals.ICU interprets the intensity distributions?

[Mike_Lauder]

1 and 2 are lumped together to form Z1.
3 and 4 make up Z2
5, 6 and 7 make up Z3

Clearly this is wrong as it would count anything between 100% and 105% of FTP as being in Z2.

You need to fudge the zones to get it to work properly.

Mike

[david]

Mike is right you need to do some fudging. But I think that is unavoidable because you need to do lab tests to figure out where VT1 and VT2 are right? Then map the watts back to % of FTP/CP for the zones.

[Coach_Ron]

David,

Just want to avoid further confusion so hopefully this is more straightforward.

I notice some people getting overly worked up about not falling into Polarization despite good attempts to do so. So just asking some fundamental questions.

1. How does Intervals define what is Polarized in using a 7 zone intensity model?

2. I also wanted to highlight that the “Seiler 80/20 polarization model” is based on % of sessions in the week that fall in the Z1/Z2/Z3 bracket, and not % time in zone. That is, if you want to go by the 80/20 approach. But it seems Intervals takes the training intensity distribution based on % of aggregate time which is another approach shown in research. Please confirm.

[Judah_Rand]

Maybe the hard and fast requirement for lab testing of VT1 is improving?

DFA a1 and exercise intensity FAQ

[MedTechCD]

It is suggested to use 90/10 for TimeInZone and I think that is what intervals is using to name it Polarized.
I’m also following the DFA Alpha1 discussion as it seems very promising. You would need HRV during exercise and Kubios std to evaluate an estimate of LT1 afterwards or HRV logger app to get it in real time. But HRV logger is only available on IOS for now. I have Android…

[Coach_Ron]

Forget about HRV Logger and all that. Complicated for most people. I mean a simple talk test should be enough to suggest your RPE is outside the bounds.

My question was only what is Intervals.ICU approach? Whats the simplest way we can check 7-zone to 3-zone relation and the computation of the classification?

90/10 for TIME IN ZONE Z1/Z3 by heart rate you mean @MedTechCD ? So how will that look in the traditional 7-zone Friel (or Coggan zone approach). We could make a quick spreadsheet to map this out but I was hesitant to get into all that now.

[John_Peters_endura.f]

Here are a couple of resources you might find useful

Jamie Stanley (jamiestanley85)

Peter Leo (peter__leo)

[Mike_Lauder]

The classifications, based on Time in Zone, for the different distributions are as follows (in hierarchical order):

HITT: S3 > S2 and S3 > 0.499 x (S2 + S1)

POLARIZED: S3 > S2 and S1 > S2

BASE: S1 > 3.99 x S2 and S1 > 3 * (S2 + S3)

PYRAMIDAL: 1.4 x S2 < S1 < 3.01 * S2 and S2 > 1.4 x S3

THRESHOLD: S1 < 4 x S2 and S2 > 0.5 x S3

UNIQUE: None of the above satisfied.

(S1 = Z1 + Z2, S2 = Z3 + Z4 and S3 = Z5 + Z6 + Z7)

Mike

[Coach_Ron]

Thanks @Mike_Lauder . Sets the record clear. I couldn’t find this information anywhere.

So as per this, there are no hard % numbers associated with the classifications
As long as any session meets the criteria S3>S2 and S1 > S2, it should be “polarized” for example.

Few remarks :

A) One of Dr. Seiler’s work looked at TIZ vs session goal approach when analyzing by heart rate. His group found that (75/8/17)% in (S1/S2/S3) by a session goal approach corresponded only to (91/6.4/2.6)% in a TIZ approach. In other words, the time spent between VT1 and VT2 heart rates was greater than that spent > VT3.

B) Not trying to split hairs, but the lower end of S2 (i.e Z3, tempo) which can easily correspond to a RPE~4 effort for many well trained athletes could be considered part of S1. But that is best left to the athlete/coach in the “fudging operation”.

I’m just not sure how many well meaning athletes are seeing their training fall outside of polarized if they like to train in a nice steady state tempo (not even touching “sweetspot”, <88% FTP)

C) One would hope that zones set in Intervals.ICU corresponds to physiological reality. Ideally, as @david points out. i.e Z2 upper should be < VT1 and Z5 lower should be > VT2. But practical reality is people dont have access to VT1/VT2 data, so they likely fall back on the default zones.

D) The default Friel “LTHR” 7 zone model works obviously with lactate threshold heart rate as the defining metric. And the 3-zone polarization was described using VT1 and VT2. Although there is correspondence between VT1-LT1 and VT2-LT2, not sure if it is always that clean. Dr. Seiler himself wrote

“However, for some individuals, and perhaps in general for activities like cycling and speedskating, the LT2 (MLSS) may be substantially higher than 4mM (Beneke & Von Duvillard, 1996)”.

This is probably going down another rabbit hole so ending here.

[Olly_Thomas]

Excellent resources - thanks for sharing.

[Mike_Lauder]

Yeah, it’s not published on the site but @david has posted it a couple of times on here.

@Coach_Ron

As long as any session meets the criteria S3>S2 and S1 > S2, it should be “polarized” for example.

I honestly don’t think it’s that useful to be looking at a session and say whether it’s polarized or not. Just get the work done and keep an eye on your overall distribution.

I didn’t make it clear that the list is hierarchical (edited my post to say that) so if the distribution fits HITT and POL it will be classed as HITT. For instance, the following satisfies both but is Classified as HITT:

S1, = 50%
S2 = 10%
S3 = 30%

On another note:

Folk often latch onto no. of sessions too much. Seiller was looking at cross country skiers, rowers etc who all do multiple session in a day of roughly equal time - perhaps up to 13 or 14 in a week. Cycling is a bit different to that given we love a long single session of multiple hours. I believe it would be wrong to equate a 5 hour ride with a 1 hour interval session. I would be inclined to look at session time rather than number.

Mike

[MedTechCD]

Time in Zone by Power numbers, yes.
It’s difficult to correctly identify S1/S2/S3 when doing shorter intervals. Heartrate is rising to slowly when starting that hard interval, hence the different % Power/HR.
Heartrate during shorter hard effort, goes S1–>S2–>S3 while actually should all be S3. It’s better to identify Power corresponding to VT1 VT2 limits.
And Polarized training should be looked at over a period of at least a week. One session isn’t telling you anything.

[Coach_Ron]

Thanks.

The way I interpret Dr. Seiler is that he is okay with using % of total weekly session time as a second approach. He seems to prefer the number of sessions approach. So in his analysis of past descriptive studies, he has concluded that a common intensity distribution was quote :

“80% of training sessions are LIT intensity and the remaining are performed as ThT or HIT. For an athlete training 10 to 14 times per week, this means that two to three of these sessions would be ThT or HIT training bouts.”

[Coach_Ron]

Thanks.

One session won’t tell you much about long term distribution. I think Intervals.ICU is the first time I’ve seen training classification based on a single days worth of work. But its probably good to keep that in the tool, for those who like to focus on the micro details and work outwards. In theory, if all the single sessions are polarized for example, your week should end up being polarized.

[Coach_Ron]

Thanks John. I have yet to check out the spreadsheets.

I made one for my purpose real quick to map a 7-zone CP model to a 3-zone model, based on power, HR, RPE etc. All based on published guidelines and for a hypothetical athlete.

Athlete weight : 75kg
CP : 250W. Assume established from 1/time 2-parameter model
HR@ CP : 180bpm
Max HR : 190bpm

First, the 3-zone model :

Here is the 7-zone CP model :

Conclusions if you go by power output as metric :

1. Upper end of Z1 in 3-zone model = 200W. This region corresponds to Z1 upto a tiny excursion into Z3 in 7-zone CP model.

2. Lower end of Z3 in a 3-zone model = 250W. This region corresponds to top half of Z4 and above in a 7-zone CP model.

Therefore, the much despised Z2 in a 3-zone model overlaps with top half of Z3 and lower half of Z4 in a 7-zone CP model. Going by the guidance, that looks to be somewhere between MLSS intensity (~field correlate FTP) to CP (boundary of very heavy and severe domains where drastic metabolic disturbances are found to take place).

I’m getting a better perspective on things after I did this mapping. I need to share this with Dr. Skiba and just get some of his thoughts as well.

This spreadsheet is available for anyone , please request it if you need it to play around.

[david]

Tx guys for all of this and for @Mike_Lauder for digging up the Intervals.icu rules. I am currently riding 5 days a week so glad to hear that more than one of those can be hard and that time-in-zones is “ok” for some definition of ok!

[Coach_Ron]

@Mike_Lauder

FYI. With reference to hierarchical TID between POL and HIIT, Stöggl and Sperlich (2014) classified the following as POL and HIIT. Note that 68/6/26 was still POL according to them. That’s close to your 50/10/30 example. Would Intervals.ICU classify that as HIIT? Please clarify.

[Clifford_Smith]

I have heard Seiler say more than one time that people get too focused on the exact specification and percentages. The actual physiology is somewhat cruder. Focus on having some, hard/intense work (~ 20% of sessions) and keep the rest easy.

Even what is categorized as hard/intense is dependent on the athlete and their goals. For some, hard may be threshold or even just sub-threshold work (e.g. triathletes) for others it’s harder stuff.

Anyway, that’s how I keep myself from going insane.

[david]

@Coach_Ron

Note that 68/6/26 was still POL according to them.

Thats also POL in Intervals.icu.

@Coach_Ron

50/10/30

This one is HIIT.