VO2max 4x4min - done right?

Training
1

Hi!

I just did some 4x4min VO2max - now loking at the numbers I am not sure if done right or where to improve for the next VO2 workout.

According to the analysis I spent just 8min above 90% of my HR max, also the first two intervals show no HR in the red zone (which reflects > 90% HR max), just happend from interval #3 on.

Also, I was able to bump up interval #4 up to 332 Watt average.

My unedcated guess would be, that I startetd the first two intevals to low but will be happy to hear some other feedback, thanks!

Watts / HR in the upper part are averages.

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2

There are many approaches, this is my opinion based on what I understood from Kolie Mooreā€™s podcast.

You probably need to start harder, then drop power and settle in. Donā€™t really base anything off power targets, but your ability may be higher than most in this zone so youā€™ll need to push on a bit to get the heart rate up

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3

I am relying more on breathing rate than HR:

  • breathing has faster response, while HR has lag
  • at VO2max intensity (whatever it is for you individually), your breathing becomes very rapid and difficult to sustain. It indicates you are hitting aerobic ceiling (goal)
  • and this is direct reflection of oxygen demand

50+ breaths per minute is good target. I frequently donā€™t even reach correct HR zone, especially with longer intervals (5-8min)

4

Takes me about 2min to reach 90% hr in first interval and 90s or less in the later ones without hard start when Iā€™m fairly fresh.

5

Thanks, IĀ“ve also read his name quite often but never listened to his podcast. Do you have a specific episode in mind? The one from endurance innovation is not available any more :frowning:

6

Thats a good point, thanks. I will take a closer look at this for my next VO2max workout.

7

Was not thinking of this, but sure, it seems to be a good indication. Do you measure your breaths per minute or rely more on breathing style?

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8

the 30s power makes it a bit hard to see whatā€™s happening at the start and end of each but at first glance:

  • The first 2 intervals were too easy
  • You should start each interval a bit harder and let power naturally fade a bit as you keep effort and breathing maxed out
9

I read it like that at first too, as itā€™s how mine is set upā€¦ His is 30s heart rate though

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10
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11

Yes, alexgold123 is right - no watts shown in this charts, my fault. But I would now agree that the 2 were too easy and start should be harder.

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12

Great, thanks!

13

If you want to really go deep, there are some links to big discussions on the topic here: Hard start vo2 max

14

I have counted breaths couple times, to familiarize myself at which point breathing style reaches to goal state. Now I rely just on perception: shallow and rapid breathing ~1-2x/sec, canā€™t speak at all. After interval it takes around 15-20 sec to be able slow breathing down.

15

Why are we doing this type of VO2Max intervals at constant power or constant time (speaking of this type specifically, not hardstart, or all out types). The first intervals always feel too easy, and the last ones too hard. Why donā€™t we do decreasing power interval from interval, or decreasing time like 5:00-4:30-4:00-3:30 ? If well calibrated all intervals could feel equally difficult.

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16

People do. They are called cut down intervals or ladders. Itā€™s common in the running world.

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17

Yup. Thatā€™s what motivated me to design the following series of workouts - with hard start, and declining power.

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18

Yeah this is what I do. My coach gives me constant time (I think that just makes it a bit easier to track progression and improvement through a block and fatigue through the workout. But each interval is intended to be max effort. So that naturally means there a 5-10% drop in power from the first to last interval.

That drop isnā€™t prescribed since the workout just said ā€œmax effortā€ but it is expected and happens naturally.

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19

Ahh yeah I missed that, so I take back that the start was too easy since you canā€™t really see that here. HR is going to lag somewhat anyway no matter how hard you start.

I donā€™t do an intentional ā€˜hard startā€™ but the power sort of naturally falls throughout the interval. So for example, if I do an interval with average power of 330W (like yours) I might have a power ceiling of like 400W that Iā€™ll try not to exceed at the start but Iā€™ll probably average like 350ish for the first minute but then down to like 315 in the last 30-45s or so

20

It is pretty hard on TR to find decent 4x4 and proper tabata workouts. I found Vandever-1 4x4 @112-114% 4 mins recovery any other decent ones out there?