Thank you. And you’re probably right - the internet is not an environment conducive to nuance! 
Thanks for the reply, and this is kind of what I was after. My thinking though was that if any study can be faulted or perhaps doesn’t take into account some specific variable or maybe something is overlooked, is there really enough evidence out there that can validate that PYR>POL or they POL>PYR, and if not, why did TR choose to omit what are considered POL plans in favor of PYR?
I’m sure there is no one end all be all training method that works for everyone, and I would think it would be irresponsible to simply replace the existing plans with POL because it becomes a popular discussion. What I don’t understand is why they weren’t offered as an OPTION, even if TR thinks they are less effective, or less proven, but we have the traditional base plans which fall into the same “we don’t really recommend this” bucket.
I’m not arguing the science or data, frankly it’s all a bit intimidating (and you did a great job breaking it down into layman language by the way) just don’t know why it took so long to have the option there
I think the TL;DR of all this podcast boils down to
TR is not just sweet spot
POL might give better results if adhered to (aka you have time)
Shorter workouts get better adoption/compliance rates so they’re put the forefront of the workouts people will actually do.
Because in the end, the workout you do is better than the workout you don’t do.
I can attest that the above ('start doing vo2 and o/u pretty early) is true. Not happily either…given my dislike for VO2… 
@Jonathan unrelated to the content, will this episode be available in the podcast feed or only on youtube?
It will be on audio feed too. I managed to DL the “bad” episode prior to it’s removal.
I think it’s a safe bet that they will publish on the usual audio channels when the updated version is done.
I read them…
I suspect many of the plans may come out with a PYR structure only by virtue of the recovery week and not due to a PYR structure week-by-week. For example, I did weeks 2 to 6 of the SSBMV1 plan a few months ago and my weekly distributions looked something like:
WK2: 49.4% 45.1% 5.5%
WK3: 46.8% 50.6% 2.6%
WK4: 45.6% 50.0% 4.4%
WK5: 42.6% 54.0% 3.3%
WK6: 97.3% 2.7% 0.0%
Overall: 55.8% 41.0% 3.2%
So although the overall volume could be classified as PYR the structure of the work weeks is Threshold. This is different to the referenced studies that maintain a consistent PYR structure throughout I believe.
You bring up a good point re: timeline, and I think this is one of those between-the-lines points that often gets lost in these discussions. It’s long been a practice among athletes to increase low-intensity work and substitute higher intensity for moderate-intensity at different points in a competitive season (i.e. to "p"olarize their training): for example to dump fatigue and sharpen the top-end form during a taper for an event, or while in a heavy competition season where racing constitutes most of the intensity work and recovery becomes more important than increasing fitness. Small “p” polarizing has been a component of periodization for a long time. It wasn’t until 2004 that Seiler coined the term “Polarized,” and it’s taken even more time since then to see interventional studies testing what Seiler and others saw emerging as a POL ratio in observational data. Noting my previous reply about the dearth of studies and the need to develop a robust body of research to responsibly infer conclusions, the identification and investigation of Polarized as its own separate TID is relatively recent in the literature. While not as bad as geologic time (!), the pace of research doesn’t track in real time, given these studies can take years from inception to publication. This is probably why Polarized Training wasn’t immediately popular or implemented in those first couple of years, but has gained in popular awareness more recently. The idea of applying a single TID to a whole plan is also not well founded, even in the research showing POL as a promising TID. Researchers have yet to examine POL as a TID in longer-term or even season-long studies for cycling, or to examine POL as a stand-alone TID vs. a TID implemented in combination with other TIDs within different periodization models.* At TR we don’t take a position regarding TIDs; instead we look to the data (both in the literature and in our own database). So far, there isn’t clear evidence in the literature on cycling that supports the idea of building entire plans (i.e. multi-block, season-long, or longer) using exclusively a POL TID. That said, many of our athletes are eager to try it, so we see that as a win-win: offer the option for athletes to experiment, and we all learn something in the process.
*For reference, a (recent!) 2018 Review of POL studies in the literature could only find 3 studies that met the following criteria for meta-analysis: random allocation of subjects, endurance-trained athletes w/ >2y training experience + VO2max > 50ml/kg/min, a POL group, a THR group, and assessed either internal (physiologic) or external (performance) outcomes. Of those, only two of the studies included cyclists. Of those two, only one looked specifically at cyclists (n=11, started as 12 could only analyze 11) and the other pooled athletes from several endurance sports including cycling (cyclists were n=15). It’s a good example of how few studies there are on the effectiveness for POL TIDs in cycling.
The right tool (TID) for the job at the right time.
Gone from my device, gone on Apple podcasts, YouTube gone too
Dear Amber, there may be more recent studies since the 2018 meta-analysis such as this one by Rivera-Kofler et al:
Abstract Currently there are two most used training models that condition the work methodology in endurance athletes: Threshold Training (UMB) and polarized training (POL). The objective of the present study was to compare the effect of both programs on the aerobic performance of trained cyclists. The research included 18 athletes who were randomly distributed in the BMU group (n= 9; age 38 ± 7 years; height 171.8 ± 6.9 cm; body weight 74.10 ± 10.94) and the POL group (n= 9; age 31.4 ± 12.2 years; height 167.5 ± 6.7 cm; weight 63.88 ± 5.37) who completed 4 weeks of training. Both methodologies were executed under similar characteristics in terms of total training time (BMU; 1085 min / wk; POL; 1024 min/wk) but with different intensity distribution (BMU= 70% in zone 1; 30% in zone2; 0% in zone 3; POL= 88% in zone 1; 0% in zone 2; 12% in zone 3). Body weight (kg) and functional threshold power (PUF) were measured before and after each programming. Only group with POL load reduced their body weight after the program (POL= -1.38%;p = 0.003). Also, group POL improved their PUF (5.48%; p= 0.012) and by default the watt values per kilogram of weight (V/kg) they were increased (7.17%; p= 0.015). Compared to UMB intensity distribution, 4 weeks of POL training improves aerobic performance in trained cyclists.
LINK: Vista de Efecto de dos programas de entrenamiento con diferente distribución de intensidad (polarizada vs umbral) en el rendimiento aeróbico en ciclistas entrenados (Effect of two training schedules with different distribution of intensity (polarized vs threshol
@Jonathan, for episode 300, are you all going to dress up like Spartans as in the movie 300? Seems like there should be some theme or something for such a big milestone!
I can’t find Episode 299 on YouTube or my podcasts. From the comments, people saw it live. Any idea when it’ll be viewable/audible for those of us who couldn’t catch it live?
@Jonathan might want to put a note somewhere on the first post to explain the take down and re-upload of the episode since you’ll keep seeing threads/replies popping up lol
Oh yes for sure! I didn’t mean to imply there had been no studies since then. Only to offer an example that, as recently as 2018, it was difficult to find interventional studies specific to cycling. Thanks for clarifying that and for sharing this study! As a reader, I’m eager to see studies with more than n=10 per Training Intensity Distribution, but from the research perspective, it’s very understandable given the complexity of designing and conducting studies like this. Regardless, it’s so fun to see the research emerging!
Make ready your bike, for tomorrow we ride?
Maybe the a live podcast and group training session combined?