Why Anaerobic Work Hurts — and Why We Train It Anyway

One of the most misunderstood sensations in training is that deep, burning discomfort that shows up when efforts go long and hard. Athletes often label it simply as “lactate” and assume it’s something to avoid.

In reality, learning to work with lactate — not fight it — is a key separator between good athletes and very good ones.

Let’s break it down.

What Lactate Actually Is (and Isn’t)

Lactate is not a toxin. It’s not “bad.” It’s a normal byproduct of fast energy production.

When intensity increases beyond what your aerobic system can fully support, your body turns to anaerobic metabolism to meet the demand. This pathway produces energy quickly, but it also produces lactate and hydrogen ions.

Important distinction:

  • Lactate itself can be reused as fuel

  • The discomfort comes mainly from the accumulation of hydrogen ions, which interfere with muscle contraction and nerve signaling

So lactate is not the enemy — it’s a signal that you’re operating at a high level of demand.

The Critical Time Window: 0–90 Seconds

When you first go hard:

  • The body can buffer and recycle much of the lactate being produced

  • Breathing increases, legs feel heavy, but power is still manageable

  • Coordination and rhythm are mostly intact

For roughly the first 60–90 seconds, strong athletes can stay in control here.

This is why short anaerobic efforts often feel “hard but doable.”

After 90 Seconds: Why It Gets Really Hard

Once you pass ~90 seconds at true anaerobic intensity:

  • Lactate production exceeds clearance

  • Hydrogen ions accumulate rapidly

  • Muscle contraction efficiency drops

  • Breathing becomes urgent and less controlled

  • Power becomes harder to sustain

This is the moment athletes describe as:

“It suddenly feels like the floor drops out.”

Nothing magical happens at 90 seconds — it’s simply the point where physiology catches up with ambition. And this is exactly why we train here.

What Anaerobic Training Actually Improves

This type of work teaches your body and brain to operate under stress:

Physiological adaptations

  • Improved lactate buffering

  • Faster lactate clearance and reuse

  • Greater tolerance to acidosis

  • Better ability to sustain power under fatigue

Neuromuscular adaptations

  • Maintain form and coordination when tired

  • Delay loss of pedal smoothness and force application

Mental adaptations

  • Staying composed when discomfort spikes

  • Not backing off just because it hurts

  • Learning the difference between pain and failure

This is not “junk suffering.” It’s very targeted stress.

Why We Progress Reps Over Time

We don’t start by living deep in that discomfort.

A smart progression looks like this:

  • Shorter reps first (around 2 minutes)

  • Gradually extending toward 3-minute efforts

  • Carefully managing total volume

At the high end, 15–20 minutes of total anaerobic work, typically done as 3–5 minute reps, represents elite-level capacity. That’s top of the line and not something you rush.

How This Transfers to Real Cycling Performance

This work shows up everywhere:

  • Bridging gaps

  • Responding to surges

  • Sustaining hard climbs

  • Holding power late in races

  • Staying aggressive when others fade

Athletes who can tolerate lactate don’t panic when intensity spikes — they lean into it. Anaerobic work is uncomfortable by design. But when applied correctly, it’s one of the most powerful tools we have to raise performance ceilings. The goal isn’t to suffer blindly. The goal is to expand how long you can stay effective once things get hard. Train it with intent, progress it patiently, and respect the stress — and it will pay you back on race day.

Mental Cues for the 90–180 Second Window

This is the window where most athletes give time back — not because they’re empty, but because their brain starts negotiating. Having cues ready before you enter the effort is critical.

0–60 seconds:

Settle, don’t spike

What’s happening: Effort ramps, breathing rises, legs load.

Mental focus:

  • “Smooth first, hard second.”

  • “I’m setting the table.”

  • “Relax the face, relax the shoulders.”

Cue: Control early so you have room later.

60–90 seconds:

Commit

What’s happening: Discomfort is noticeable, but still manageable.

Mental focus:

  • “This is exactly where I’m supposed to be.”

  • “Stay tall, stay smooth.”

  • “I choose this effort.”

Cue: This is the buy-in phase — no backing off.

90–120 seconds:

Don’t react

What’s happening: Lactate floods, breathing spikes, legs burn.

This is where most athletes panic and fade.

Mental focus:

  • “Nothing is wrong.”

  • “This feeling is temporary.”

  • “Breathe out longer.”

Cue: Observe the discomfort, don’t negotiate with it.

120–180 seconds:

Execute, not survive

What’s happening: Power feels fragile, form wants to fall apart.

Your job is precision, not heroics.

Mental focus:

  • “One more pedal stroke.”

  • “Strong circles.”

  • “Calm pressure.”

Cue: Narrow the focus — shrink the moment.

End of the Rep:

Finish with intent

How you end reps matters.

  • Don’t quit early.

  • Don’t surge wildly.

  • Finish in control, even if it’s ugly.

Cue: Finish strong, recover proud.

The Key Mental Skill This Work Trains

Anaerobic training isn’t just about physiology — it teaches you to:

  • Stay calm when your body is loud

  • Separate sensation from danger

  • Keep executing when comfort disappears

Athletes who master this don’t fear surges, climbs, or late-race pressure.

They recognize the feeling — and know they can stay with it.

Cycle, TrainingMarilyn Chychota