VO2 max or anaerobic intervals?

Hi everyone, I am a bit puzzled by the following. My current FTP is about 270 watts (ramp test), my one hour power record is 275 watts, and my 20 min record 300watts.
From these numbers 120% of my FTP is about 324 watts (if 270) to 330 watts (if 275)
The other day I did the following workout: 5x3 minute with 3 min rest between intervals at 338w the first 4 and 325w the last. I think I might be able to progress the efforts to 340-350w soon.
My question is, these numbers as a % of FTP are above 120, therefore will I be working on my VO2max or on my anaerobic capacity?
I ask because this workout is short yet very hard and seems productive but I would like it to translate into higher power for longer time durations like 4 to 8 minute lets say, not that it just improves my 1 to 2 min power.
What are your thoughts?
Thanks in advance.

Rather than increase the intensity of the on interval why not extend the duration first? So try 4 min intervals and see how you are getting on. Then try 5 minute intervals etc.

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Did you test your hour & 20 min and ramp on the same equipment?

FTP is an estimation of your hour so to do more in a real hour ride is damned impressive, most people get an estimated hour (FTP test) of NNN watts and rarely actually achieve an hour at that level.

Yes same power meter: Favero Assioma

The 120% is just a guideline. As I understand it, there is no physiological “switch” that trips when you cross 120%. Anything above threshold is at least partially anaerobic. VO2max is a physical state (maximal oxygen uptake) rather than a power level. So you can get there via long intervals at lower power (say, 110%) or really short intervals at say 130%. I’ve heard people say you can theoretically get there by riding at like 102% for a long time, but realistically your legs will fatigue first. There’s also some individual variation. For me 60/60s have to be at more like 130% to elicit VO2max, for example.

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Yes that is also my plan but I was thinking to really push the raw power up first because I feel my endurance and threshold are OK

I assume the power hour of 275w was average power. If so that is the best, most ideal, measurement of your FTP, the ramp test or 2x8min or 20 min are all estimations aiming to make testing quicker, easier and more repeatable than a full hour. Use that as your basis.

About 4-5 years ago Dr. Coggan updated the training zones above FTP, removing the VO2max and Anaerobic zones and replacing with Individualized Zones. The reasoning behind it is classic zones having a limitation when using a fixed % for zones above FTP. One relevant quote from that article:

“As shown in Figure 3 below, their relative power was generally similar at durations more than about 10 minutes. However, there is obviously a very large (approximately fourfold) difference in the extent to which they can elevate their power above FTP at very short durations. As a result, the one athlete can maintain a power of, for example, 150 percent of FTP for about 4 minutes, while the other athlete can do so for only about one minute.”

The classic 3, 4, and 5-min vo2max intervals are meant to be done at max repeatable power for YOU.


So in conclusion as long as it is repeatable I will be challenging the VO2max energy system?

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Yes, max repeatable. Ideally there is little to no dropoff in power between the first and last interval. Without pulling out the Training and Racing with a Power Meter book, I think the guideline is to keep interval power within 5% or so (it varies depending on interval length). These are intended to be max repeatable efforts, and should feel very difficult.

Hello, i am not sure this is right place to ask it but i have confused about vo2max and fatigue situation.

Today i did Pisgah+6 which is two sets of 4x4´ 102% ftp followed by 30´ 65%.

My heart rate was low (my max 180-182 but my 4 mins lap avg hrs were 157-159 range) i guess it is because of fatigue ( i feel good but my legs were really tired i felt).

So my question is that my heart rate was low and after the workout my vo2max became 64. So can i count it as a pr (or its just because of fatigue and your vo2 did not increase?)