That’s what I’ve done. I’ve created a small number of simple workouts that target different energy systems that I use at different stages of my season and I just use them over and over again. For sure it doesn’t provide much variety, but I usually execute them in Zwift or outdoors, so that provides the distraction factor for me.
Also, the meaning of ‘intensity’ varies for me - early on it will come in the form of sub-threshold work twice a week (my ‘20%’ of sessions). Later I’ll do actual threshold work and only really reach into the true POL Z3 stuff (120%+ of FTP) in the 4 or so weeks prior to my ‘A’ events given that it doesn’t take much to build that system especially once you have a solid base foundation. This works for me as my events tend to be in the 100 to 180km range. I’m no crit racer!
1 Like
Not a digression at all. This study you mention is one of the Dr. Seiler’s highly cited studies into interval training adaptations using an iso-effort protocol.
The gold nugget in that paper is one statement within the Discussions section, which most people do not talk about but you bring up rightly.
“We also found that RPE of the interval training programs was more strongly associated with work intensity than accumulated duration.”
This bit right here takes the cake. As I mentioned before, we need to find a way to bring RPE into the weekly TID analysis to provide an overall picture of the “how hard” part and help facilitate a conversation between coach and athlete.
I’ve written the HOW-TO part, now someone just needs to help make that happen.
As for the 4 x 8 mins at 90% HR, if you map it to the 3 and 7-Zone map in my map above, you’ll see it clearly falls in the Z3 and S3 areas respectively. Those looking for a “bang for the buck” HIIT workout for POL training can experiment with incorporating 4 x 8 min intervals as part of the HIIT.
The exact protocol was 2 days of 4 x 8 minutes with 2 minute recoveries, in addition to 2-3 weekly endurance sessions at low intensity, for a total of 5 days/week of training. Clearly this was Polarized.
The study lasted 7 weeks.
1 Like
+1. My takeaway was this.
-
For a HIIT session, the shortest intervals with the highest RPE didn’t confer the same benefits as slightly longer intervals at lower RPE in recreational cyclists.
-
The study was done on 35 trained recreational cyclists. I have some reservations about extending the findings of this paper to highly trained and elite athletes; the latter section tends to have different recovery characteristics and different training needs to elicit performance gains. Not sure if Dr. Seiler ever thought of repeating said study in a different class of athletes.
2 Likes
Thanks. There are “levels” to periodization of Polarization, if you will.
Currently its an interesting question how the intensity levels can and should progress but I suspect this will always be what works for n=1’s main event. You can either :
- Keep LOW at the same level and increase HIGH as race approaches with volume reduction.
- Intensify both LOW and HIGH with volume reduction, since VT1 and VT2 could right shift over time.
- Or you try a mixed approach between both based on how you are adapting (“adaptive” strategy)
There are no cookie cutter methods as you highlight.
2 Likes
Hoo boy. The thought of a 4 x 8 min ‘as hard as you can go’ workout is something I’d have to really psyche myself up for! 
2 Likes
I did the 2x8m FTP test (10min rest in between). That was after an hour endurance ride as a warmup. I know it’s not supposed to be an hr warmup but I didn’t have a trainer then so had to get to the spot I’d chosen to do the test. I had just got my power meter the day before. Like TrainerRoad’s ramp test, it’s only the final part (2min maybe) of each interval that is really hard. It’s not supposed to be easy 
I’ve loaded a 4x8m workout onto my Wahoo Bolt and will probably do it next week. I’ve set it at 10% FTP but will adjust if necessary.
I actually like the 2 x 8m FTP test. It seems to produce what seems like the right FTP number for me unlike the 20m test which I struggle to pace or the ramp test which doesn’t seem to suit my physiology and under-reports my FTP (despite it being an all-out eyeballs bleeding, max HR effort).
All this means that one’s results may vary and with estimations getting as good as they are, you may as well take those if they ‘feel’ right.
But, still. 4 x 8m max efforts doesnt seem like it would be a regular feature on my training plan.
1 Like
Where do you and @Judah_Rand see your LT1 HR falling with DFA alp1 method? And where does it fall on the 3-zone and 7-zone map I drew up.
I tested mine this morning but I’ll reserve my thoughts to Twitter in a bit; thought I’d hear your take on it first.
I had a lab test a few years ago and have been using HRV Logger recently. The DFA a1 measurement is a tricky one, but when it seems to go right it matches my tested LT1 of 142 - 144 BPM on a 190BPM Max HR. This fits the standard models surprisingly well.
That’s promising. Could you explain “tricky”? Is it an equipment issue, or issues with post-processing?
Well, I didn’t have so much of a good luck on the initial try.
The 3 and 7-zone were far out of DFA a1 indicated power and HR. Reptitions of trial to be done in the following days.
I laid out a Twitter thread on my trial this morning.
https://twitter.com/RonGeorge_Dubai/status/1365939113111789571
I found that on yesterday’s long easy Z2 rides the DFA a1 seemed to jump around a bit, making it difficult to get a good number from it. However, I did an easy interval workout targeting my LT1 HR (5 x 8 min) last week and once I was warmed up, it ended up matching pretty well on each interval. That’s just two recent examples.
As I said, hit & miss and I only know that because I know what my LT1 HR is from a previous lab test. Lots of apparent equipment-related challenges too! Anyway, it’s a promising idea, hopefully it develops further.
Long easy rides done indoors? (or out?)
Not sure why the hit and miss, but I have more testing to do. From reading Rogers et.al’s paper, HRV signal is suggested to be strongly correlated when you’re riding well below VT1. It transitions to uncorrelated and less complex at the value of HRVT = 1.0 - 0.5 as intensity increases, in a rapidly linear drop fashion.
Maybe it is during the intervals that this signal makes a pronounced crossing into uncorrelated territory and you see the nadir? Have you tried reaching out to Rogers or Gronwald?
It was a very steady (VI=1.03, D=2.63%, 3h15m) easy indoor ride on Zwift. I was well-hydrated, rested and cooled.
I think you might be onto something - the transitions on the short workout make it more obvious where a1 was?
Here’s the HR, a1 chart for that ride. I haven’t done the same for the long ride yet.
For contrast, here’s the chart for the 3:15 ride I mentioned above. You can tell it is still below my LT1 given where the DFA a1 is, but that’s about it - even when the inevitable drift sets in and my HR starts to approach (but not pass) my LT1, it’s not obvious. In fact the opposite might be true? DFA a1 seems higher in that last hour than the first?
1 Like
If you ask me, like anything in the HRV world, I would tell this is “open to interpretation”. I can’t understand the bit about heart rate drift but a1 = 0.75 being unchanged. Does that mean you do not cross intensity boundaries in hot weather? Muscle glycogen usage does shift around with heat, so not sure.
Early days, but as it gets adopted, we might see better tools made for it. I can’t see myself riding outside with a 3-lead ecg poking my eyes into an HRV logger.
Frankly, on the “easy” LOW days of Polarized training, you shouldnt have to monitor anything particularly even power. The simple “go by feel” RPE would trump all of this.
1 Like
Yup, I was confused by his statement around HR drift and it not impacting DFA a1. Well, i’ll just keep watching its development.
Luckily, this is all just intellectual curiosity for me. As you say, those long slow rides should be done on feel. They should be easy. Your HR should remain steady and ‘low’. That’s how I ride them.
@Clifford_Smith Bit puzzling but more data is necessary to see if this remains the case on long rides.
When heart rate drift happens, R-R time span should decrease. That’s no different than working at a higher intensity, as heart rate would increase in that scenario too. In your graph, I can see a1 increasing and decreasing where Rogers indicated a straight line with the green ink. As to why there’s no net downward trend on DFA a1, I do not know.
Here’s a plot of real heart rate drift and marathon run speed in a certain study on marathon pacing. The speed was very steady, until runner hit the wall. The sharp loss in speed corresponded to the drift and change in “fractal scaling of the heart rate”. If we hooked up this HRV logger to this chap, I wonder what we’d find. If DFA a1 stayed steady despite the drift, the utility of the tool would mostly be lost.
Who knows! It doesn’t make sense. This science stuff is beyond me … I’m just going to ride my bike! 
Hi Ron,
Interesting reading.
I am also interested in the spreadsheets.
Are you willing to share them with me?
Thanks upfront!
Gr Johan B
