I’ve seen people reference Seiler’s 2x16 4x8 etc workouts. I have two questions.
Does TR have these workouts available?
If not, for people who actually tried them out, what percentage of FTP did you end up executing these?
Thanks
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To find the equivalent to Seiler’s workouts in the TR workouts library takes a bit of searching. I’m sure someone have already done that and can help out.
Instead I provide a link to his paper. You can get a pretty good idea to what intensities they are performed at.
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TR workout search has certain phrases to remember if you look for something specific.
For this special purpose, magic is in:
two 8-min,three 8-min,four 8-mintwo 16-min,three 16-min,four 16-min
As pedantic person, I find solace there is pattern. As software developer, I find this pattern not as helpful as it can be → Z4/4x16 would carry so much more meaning 
EDIT: if you are looking for training plans based on these progressions, look for Polarized Base and Build. Unfortunately TR dropped feature that enabled switching Plan Builder generated plan phases to those plans. Now you have to manually add to calendar.
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That’s correct @svens 
!!
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It’s not like the intervals in that study are super magical or anything. To me, the more interesting aspect of the paper is the times and intensities.
The intervals are done all out but at a power where you can complete all the intervals.
4x4 are going to be classic VO2 intervals
4x8 are going to be right at threshold or slightly above. call them threshold plus or vo2max light
4x16 are probably going to be more like sweet spot for most participants
The intervals aren’t work matched. 16 minutes for the 4x4, 32 for the 4x8s, etc.
The best “plan” is probably going to be a combination of some VO2 work and then building out TTE at threshold.
In the paper, they are calling the 4x8s the best bang for the buck:
" Put in the popular vernacular of training investment and reward, cycling 4 8 min intervals at 90% HRmax yielded the highest gain for the pain."
The discussion section of the paper is a good read on intensity vs. duration.
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I agree. There is no need to go balls out pushing HR to the max. Time in zone (HR-Zone roughly 90%) is more productive. Months ago I took a closer look at this trial and came to the conclusion that the optimum interval length would be 9min 30s …
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In the paper, they do say that the 4x4s showed more cardiac adaptations. To me that says to train all the intensities. Do some 4x4s and some 4x8s or 4x9:30s.
They could have lit the training world on fire if they had a group that did both 4x4s and 4x8s. Or maybe 4x4s one day and 4x16s building out TTE on another day would have been the best overall?
The 4x8s may be the best bang for the buck if you are just going to pick just one interval.
In that discussion they also talk about fatigue which is interesting:
Based on the group difference in RPE reported throughout the study by the 4 4 min group, we can speculate that they experienced greater residual fatigue from the training intervention. If this is true, we might also speculate that they would have shown a greater improvement after training had they rested longer than the other two interval groups.
With a better taper, it’s possible that the 4x4s might have come out on top. The other interesting point that jumped out at me was this:
Independent of the training group, subjects who reported no weekly interval training (n 5 11) in the 2 months before study start tended to achieve greater average improvement in VO2peak, PowerVO2peak, and Power 4 mM
In the group of subjects, regardless of the interval group they were in, the subjects that hadn’t done intervals for 2 months had the greatest improvements. You read that and think ‘no duh’ as it sounds totally logical. Maybe the best intervals do do are always the ones you haven’t been doing?
It’s a great paper and a great discussion IMO but it’s not a nail in the coffin for other intervals. The 4x8s are the “best” by some huge margin. They all yielded gains.
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I do the following
4 min 120% FTP
8 min 110% FTP
16 min 105 FTP
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My 4 x 8’ @ 105% ftp (quite all out I would say) was between 90% and 96% of max HR.
I guess that the HR % should be taken as a ballpark, since I was able to complete the workout
I think you are above 105%. 105% shouldn’t feel all out for just 8 minutes. At the end of 20 minutes, yes.
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This is the workout.
56 y, 240w ftp, 164 max HR.
Tipically the first interval is hard because I’m still warming up, the third is the worst, the last one is all out (but I can see the light at the end of the tunnel 
)
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Obviously the issue isn’t doing 105% for 8”. It’s repeating it 4 times.
It still shouldn’t be that hard. And the last interval sholdn’t be all out.
If 105% is this hard then the rider probably can’t ride for 30-40 minutes even at 100% let alone an hour.
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I think it can be that hard, I have been on two opposite sides myself:
- couple years ago, my TTE was 70min at 98% of FTP, but when attempted 4x8min at 105%, I could complete only 3 intervals and 3rd already felt like all out
- but, during current spring, after max sprint block (e.g. 5x30sec all out), I could complete 4x8min at 112%. Didn’t measure TTE at that time but I believe it might have been around 30-40min.
Don’t know the reason. Anaerobic contribution certainly improved a lot, also lactate tolerance but I am not sure how much it would help during so long intervals 
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I think the question for the ages is whether a TTE of 30minutes is valid. Clearly if you lower the FTP until TTE is “about an hour” per Coggan’s definition, then RPE for 100% and 105% should fall into place.
Lets say it was unknown territory for me: I usually do high volume / low+medium intensity training but this time over winter very low volume / high intensity training.
It was first time when TR AI FTP detection and intervals.icu estimation converged. Usually intervals.icu estimates me lower because I don’t to max efforts. Anyway, if we assume my FTP was indeed lower, it would mean 4x8min was at even higher percentage of FTP
Exactly.
Intervals.icu often tries to give me an FTP that is 20-30 watts overly optimistic based on short efforts (I’m way better at 3 minute efforts than my FTP would indicate).
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Theres a setting where you can set the floor for the time period for ftp estimation. I think i have mine at 15 min or something
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I did this in intervals.icu - made the change from 5 mins to 15 mins and it made a material difference and eliminated the bias brought about by my relatively high short power compared to my actual modest FTP.
It’s also interesting that the TR AI FTP is also more accurate (I think) than when I do a ramp test for the same reason - I can do well on a ramp test probably by relying on my short power component of my fitness and this skews (over estimates) my FTP.
AI FTP appears to take a broader look at my efforts over time and seems to (for me) give a more accurate and modest threshold estimate, which then translates into more realistic workouts etc. 
You can also just make them yourself in the Workout Creator
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