QT2.0 VO2 Max Block Comments
QT2.0 VO2 Max Block Comments
What This Phase Is Actually About
The VO2 Max training block exists for one specific reason:
your top-end capacity has become the limiter.
By the time we enter this phase, you are typically in a very Aerobic physiological state. Your Critical Power or Critical Speed is occurring at a very high percentage of your power or speed at VOโ Max. In other words, your ceiling is too close to your roof.
That sounds good - but it creates a problem.
If the roof canโt move, the ceiling canโt rise.
This block is about creating room again.
1. Muscle Fiber Utilization
Polarized work: roof and foundation
VOโ Max blocks are intentionally polarized.
Near the Roof
We do focused work:
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Above threshold
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Near VOโ Max
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At intensities that demand full aerobic utilization and recruit higher-force fibers
This work:
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Trains the body to use Type IIX fibers aerobically
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Improves oxygen delivery and uptake at very high outputs
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Pushes directly on the roof of the house
The goal is not anaerobic power for its own sake. Itโs expanding the aerobic contribution of fibers that normally fatigue quickly.
At the Foundation
At the same time, we continue to:
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Reinforce Type I (slow-twitch) fibers
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Maintain and slightly expand the foundation of the house
This matters because:
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A higher roof still needs a foundation that can support it
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Polarization prevents erosion of durability while intensity rises
This is not random intensity - it is deliberately balanced stress.

2. The Athletic Architecture Model
Lifting the roof so the ceiling can grow
Using the house model:
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Ceiling = Critical Power / Critical Speed
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Roof = Power or Speed at VOโ Max
When we enter a VOโ Max block:
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The โphysiological atticโ is no longer an attic
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It is closer to a crawlspace
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And that crawlspace is limiting future gains
At this point, continuing to push threshold work wonโt meaningfully raise Critical Power or Speed. The system has become too efficient relative to its top-end capacity.
So the goal shifts:
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Apply pressure directly to the roof
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Lift it upward
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Restore vertical space so the ceiling has room to move later
This is not about refining efficiency. Itโs about expanding capacity at the top.

3. Quality, Duration, and Fatigue Accumulation
Quality above all else
Because intensity is high:
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A large portion of training stress comes directly from intensity, not duration
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Fatigue dulls the very adaptations we are trying to create
So during a VOโ Max block:
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Workout quality is aggressively protected
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Fatigue accumulation is strictly limited
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Sessions must be entered fresh enough to push physiological limits
This means:
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Shorter sessions overall
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More recovery relative to stress
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Little tolerance for โjunk fatigueโ
As a result:
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CTL growth is modest or flat by design
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This is not a volume-building phase
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Progress is measured by capacity, not load
If CTL isnโt rising much here, thatโs not a failure - it is part of the plan.
The Big Picture
The VOโ Max block is about reclaiming headroom.
We lift the roof so that:
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Future threshold work can be effective again
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Sustainable performance has space to rise
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The system doesnโt stall at a false ceiling
If Base/Durability builds the foundation, and Build/TH tightens the structure,
VOโ Max restores vertical space.
Thatโs its job in QT2.0.
