The Pace That Matters Most

Of all the training zones you might target, one matters more than the others for race performance.

It's not your top speed. It's not your maximum effort. It's not your slow, easy pace.

It's the fastest pace you can sustain without slowing down.

This is your lactate threshold (LT). For runners, it's roughly the pace you could hold for 60-90 minutes of hard effort. For cyclists, it's the power you can sustain for 45-60 minutes of hard effort.

Why does this matter? Because most races that matter—marathons, half-marathons, half-Ironman, Ironman cycling—are won and lost at threshold intensity.

Your marathon pace? That's roughly 85-90% of your lactate threshold.

Your Ironman cycling pace? That's roughly 70-80% of your lactate threshold.

Your goal race pace is almost always determined by your lactate threshold.

Improve your LT, and you improve your race pace.

What Is Lactate Threshold?

When you exercise at increasing intensities, lactate accumulates in your blood. At very low intensities (easy runs), lactate is cleared almost as fast as it's produced. You could run all day at this pace.

As intensity increases, lactate accumulates faster than it's cleared. Eventually, you hit a point where lactate accumulation accelerates. This point is your lactate threshold.

Below LT: You can sustain effort indefinitely (lactate clearance matches lactate production)

At LT: You can sustain effort for 45-90 minutes (lactate is accumulating, but manageable)

Above LT: You can sustain effort for only 5-15 minutes (lactate is rapidly accumulating, fatigue comes fast)

Your race pace sits at or just below your lactate threshold.

How to Train Your Lactate Threshold

Lactate threshold is trainable. And the most efficient way to train it is through threshold intervals.

The prescription:

Duration: 3-8 minute repeats
Intensity: ~90-95% max effort (right at LT)
Recovery: 2-3 minutes easy between intervals
Volume: 3-4 repeats
Structure: Warm-up → intervals → cool-down
Frequency: 1-2 times per week (in BUILD and PEAK phases)

Example threshold run:

Warm-up: 15 minutes (progressive, building to race pace)

Main set:
- 5 minutes at marathon pace (threshold intensity)
- 3 minutes easy recovery jog
- 5 minutes at marathon pace
- 3 minutes easy recovery
- 4 minutes at marathon pace (shorter final rep)

Cool-down: 10 minutes easy

Total: 55 minutes Hard effort: ~14 minutes TSS: ~70-85

Alternative structure (continuous):

Warm-up: 15 minutes

Main set:
- 20 minutes continuous at marathon pace (sustained threshold effort, no repeats)

Cool-down: 10 minutes

Total: 45 minutes Hard effort: 20 minutes continuous TSS: ~80-90

Both work. The repeated version allows slightly higher intensity with built-in recovery. The continuous version builds mental toughness and specific endurance.

The Adaptation

When you train at lactate threshold, your body adapts by:

✓ Increasing lactate clearance (your muscles become better at dealing with lactate)
✓ Increasing lactate threshold velocity/power (you can run/bike harder before accumulating dangerous lactate)
✓ Improving running economy at threshold pace (you can sustain faster pace with less effort)
✓ Building muscular endurance (your legs don't fatigue as fast at race pace)

The result? Your race pace improves. Same effort, faster speed.

The Timing Question

When should you introduce lactate threshold training?

Answer: After you've built an aerobic base.

A common mistake is doing threshold work too early. If you jump into LT intervals before building easy aerobic capacity, you:

Lack the aerobic foundation to sustain the workouts
Accumulate fatigue without triggering adaptations
Risk overtraining

The periodization pyramid (from Post 4) exists for a reason:

BASE phase: Build aerobic engine (easy runs dominate)
BUILD phase: Introduce threshold work (now your body can handle it)
PEAK phase: Maintain and race at threshold intensity

CADENCE structures this for you automatically.

Threshold Training Across Sports

For Runners: Lactate threshold ≈ pace you can sustain for a marathon (roughly 12-minute mile for a 3-hour marathoner)

For Cyclists: Lactate threshold ≈ power you can sustain for 45-60 minutes hard effort (roughly 85-90% max power for a fit amateur)

For Triathletes: Threshold work appears in both cycling and running, but at different phases. Cycling threshold training typically comes earlier (more building cycles for multi-sport athletes).

The Aerobic-Threshold-VO2Max Triangle

Here's how it all connects:

Easy aerobic work builds the foundation (capillaries, mitochondria, economy)
Lactate threshold work raises your ceiling (your sustainable hard pace)
VO2Max work expands capacity (your absolute peak aerobic potential)

They're not separate systems. They're interconnected:

Higher VO2Max → Higher lactate threshold possible → Better race pace

But you need both. VO2Max matters, but only if you can sustain a high percentage of it. Lactate threshold training ensures you can.

How CADENCE Prescribes It

During BUILD and PEAK phases, CADENCE generates threshold workouts tailored to your sport and fitness level.

A runner 12 weeks from marathon sees:

2 × threshold sessions per week
One longer (20-minute sustained), one shorter (3-4 × 5-minute repeats)
Intensity calculated from your most recent threshold test

A cyclist 8 weeks from a cycling event sees:

1-2 threshold sessions per week
Intensity and duration scaled to event specifics

The app tracks your lactate threshold over time and adjusts intensity as it improves.

Ready to Find Your True Race Pace?

Most athletes guess at their race pace. They follow generic templates that might not match their actual threshold.

CADENCE prescribes threshold training at exactly the right intensity for your fitness level, at exactly the right phase of training.

You'll arrive at race day knowing your sustainable pace—not guessing.

Start your free trial and discover your true threshold.

Lactate Threshold Training: The Gateway Between Easy and Fast