That’s why I found it interesting – at least now in retrospect, during it I just found it painful 
So far I never had such a reaction, maybe it was the combination of long intervals indoors (maybe closed window equals lack of oxygen?) and high intensity after a traditional winter season with a lot of Z2 and little intensity? Also I did the workout in resistance mode, so during the last intervals I pushed a little harder than the prescribed 105% of FTP.
This explanation seems very plausible. Probably the specific combination of intensity, interval and recovery duration was just enough to get me near my point of maximum oxygen uptake.
I always test with the 20min test. A few weeks after a lactate test, it turned out that the calculated value of the 20 min test protocol is pretty close to the FTP (in terms of a 1h sustained effort) that the lab gave me. Testing always hurts. However, I have never had this feeling of lack of air. Thats also why I was left wondering what happened within my body on that day
…or his fitness is such that the last interval was what he needed for progression, or he needed to add some carbs, or fluids or salts.
When you’re racing a 1500 or 3K you’re aiming for max power/speed. When you’re training VO2max, you’re not. As I’ve said throughout these threads, when trying to train stroke volume/VO2max… power is not your primary concern.
You breathe differently when doing VO2max training, you also pedal at 110+ RPM which probably isn’t the optimal cadence (on a geared bike) for most people to generate high power for 3-5 minutes.
I think the biggest disconnect here is this focus on power generation. If I want people to maximize 3-5min power, I give them different prescriptions than if I want to train VO2max. There is a distinction there in my mind, and again we do a disservice by calling this power range “VO2max” instead of something less specific - just because you’re riding at 125% of FTP doesn’t mean you’re training VO2max.
You guys can disagree all you want with me, it’s fine. I believe in the science behind it, I see the results I and my athletes achieve, and it’s been handed down from some elite coaches who know a hell of a lot more about it than I do. You guys are free to train how you like. 
If you ride long enough above threshold you’re going to push VO2max, but I wouldn’t prescribe a 4x8 as VO2max training. But again, for my training methods, I’m not concerned about power as much. I don’t do a lot of 4x8 stuff except for early base season/offseason threshold work, and I don’t love training at 105% of FTP for really anything unless it’s specific to something.
If you force me to choose, I’d call it “suprathreshold” training rather than VO2max.
the problem is “training VO2max” is ambiguous and carries a lot of baggage. Without re-listening to the Empirical Cycling podcast(s), I can’t be more specific.
I’d suggest calling it “training for a specific adaptation to the heart muscle” which has shown to increase both vo2max and ftp in well trained athletes. Calling it “vo2max training” confuses a lot of people.
Goes back to the zone naming IMO, but yes, that’s why I mentioned training stroke volume, which is a central adaptation to maximal oxygen uptake in the muscles (VO2max). As mentioned above, training some of the more peripheral adaptations takes time and a lot of riding. Still other factors of VO2max are not trainable.
But the TL;DR is that statement about “Just because you’re riding in this VO2max power zone doesn’t mean you’re training VO2max.”
Even that is confusing LOL.
I’ve pushed my absolute vo2max to the highest levels simply by riding endurance 8 hours/week and sprinkling in some intensity on 2 or 3 days a week. Counter intuitively I’ve seemingly increased both my stroke volume and muscle uptake by doing low intensity work - and thats what we see in athletes that do 20 hours of low intensity “base” training.
I’ve increased my 3-5 minute power by simply doing 8 hours/week of endurance, and then juiced it a little more with some classic vo2max intervals.
I’d wager to say to most coaching and cycling website articles on training vo2max are about increasing power output at 3 to 5 minute durations. Not going to attempt debating if those are adaptations to central or peripheral (or both).
Its a bit of trying to claim “true vo2max” training is focused on what I’ll refer to as heart muscle “strength” training via a certain type of maximal effort. And all the other stuff that increases vo2max is childs play, get with the program and have your heart pick up the heaviest weight and flex that muscle! LOL.
Just kidding, but you see how this becomes somewhat of a pissing match over the term vo2max.
Are you saying a 3k race at 100% of VO2 max is easier than doing interval training at VO2 max?
I think he is trying to say there is a specialized form of vo2max training, unlike what you’ve seen and are familiar with, that targets adaptations to the heart muscle which have been shown (by coaches) to improve stuff that you can measure (absolute vo2max and FTP, to name two).
So everytime you read “train vo2max” understand that it means something different to Coach Kurt, because this particular form of “vo2max training” is something he wants to tell the world about. But his message is confusing because the term “vo2max training” has already been established.
Using established terms to describe something different is guaranteed to generate confusion and Internet forum fun 
Is it though?
Isn’t maximal stroke volume reached at a relatively low intensity? The heart chambers have longer to fill, and the heart muscle has to squeeze harder because it’s full?
Isn’t the theory that the low intensity volume increases left ventricle size whilst high intensity makes the walls thicker? Combine the two to improve chamber volume and ejection fraction?
For muscle uptake the low intensity helps improve that capillary bed in the slow twitch fibres. That slows down blood through the muscle enabling greater oxygen take up?
It was counter intuitive because when I got started that info wasn’t easy to find. Despite reading the Time Crunched Cyclist, CTS blogs, and Friel books/blogs it really wasn’t obvious. And then I did TR for two years and the plans didn’t exactly have a lot of endurance work, and the traditional base plans that did have a lot of endurance work had descriptions that left me feeling it was the wrong choice.
It wasn’t until I really dug deep, and this is from a guy with no background in exercise physiology, that I started to get it when reading Couzens and San Millan. And then I dug deeper into studies, and the aha moment came after listening to Empirical Cycling podcast (so hard to follow, but worth it).
So yeah, it was counter-intuitive because so much of the stuff written for average cyclists is biased towards intervals over endurance.
It’s harder… so you don’t have to breath as hard.
It isn’t so counter-intuitive - look at Daniels’ running plans; yes, there appears to be a lot of intensity and intervals in there, but he’s always talking about at least 75% of the time spent in “E” running - endurance. You do a VO2Max session, you have half of that run at endurance pace at least.
yeah I grew up in the 70s and remember long slow distance running, but then started cycling in 2016 and it seemed like everything I read - except for the Time Crunched Cyclist - said you needed to focus on HIIT if you can’t do a lot of hours. The TCS book actually laid it out but I kinda got crazy and at one point was doing a lot of intensity at 6 hours/week. Kinda worked and kinda didn’t.
This was my query after listening to the Empirical cycling podcasts on VO2 max physiology. Cross country skiing and rowing were mentioned as sports that engage the greatest mass of muscle and therefore create the greatest oxygen demand, as well as having high venuous return to stimulate the heart filling rate, as discussed by @kurt.braeckel. I had hoped running would be as good, but was listening to another podcast or resource, they said that despite using more muscles than cycling, the action is shorter (ground contact time vs continual circle), therefore often produces lower demand than cycling.
So, I think, yes.
Don’t know about that. Don’t really care, either. It’s a misnomer if that’s the way people term it, in my opinion. There’s a distinction between training for maximal O2 uptake (which is what VO2max actually is), vs. training something like maximal aerobic power.
I usually make this distinction in these conversations: MAP vs. VO2max. It’s clear in my mind; not sure I really care what other websites say.
But yes, a lot of times it is just a semantic argument, or people talking about training different things while using the same term for it.
No, I didn’t say that and if you’d like to have a discussion in good faith, I would appreciate it if you didn’t put words like that in my mouth. I was pretty clear in what I said: if you want to train to have the highest power for 3-5 minutes, then train to have the highest power for 3-5 minutes. If you want to improve maximal O2 uptake, train for that. You do that differently; both are incredibly hard.
Training for maximal heart stroke volume, as an example, will probably also raise your MAP. Training your MAP may or may not raise your VO2max.
sure and I hope you understand and appreciate the communication comedy that ensues. Even what you said about training for maximal O2 uptake requires some clarification. For example I believe all that endurance is primarily working on peripheral adaptations, but on the central side of things my RHR dropped by 12bpm as a result of drastically reducing the intensity. I’m clearly not doing any high-intensity training for maximal O2 uptake, and yet it keeps going up. And given that I’m not so young anymore at sixty one, as long as low-intensity focus continues driving vo2max increases, I have no desire to do any special high-intensity cardiac remodeling or whatever the correct term is.
I do. I try to be specific, but even that gets lost sometimes. The more I participate here in some of these threads, the less I think I should.