A training distribution where 80% of time is spent at low intensity (Z1-Z2) and 20% at high intensity (Z5+), avoiding the moderate 'grey zone'.
Polarized training is a methodology championed by Dr. Stephen Seiler's research on elite endurance athletes. The core principle is simple but powerful:
Train easy when you train easy, and train hard when you train hard. Avoid the middle ground.
Low Intensity (Z1-Z2): 75-85% of training time • Below lactate threshold 1 (<75% FTP) • Conversational pace, aerobic base building
Moderate Intensity (Z3-Z4): 5-10% of training time • Between LT1 and LT2 (75-90% FTP) • Largely avoided except during races
High Intensity (Z5-Z7): 15-25% of training time • Above lactate threshold 2 (>105% FTP) • Hard intervals, VO2 Max work
Zone 2 Work: • Builds mitochondrial density • Increases capillary networks • Improves fat oxidation capacity
• Stimulates VO2 Max improvements • Enhances lactate clearance adaptations
Avoiding Z3-Z4: • Minimizes cumulative fatigue • Prevents inadequate recovery • Avoids insufficient training stimulus
Research shows that elite cyclists from WorldTour teams like UAE Team Emirates, Jumbo-Visma (now Visma-Lease a Bike), and INEOS Grenadiers follow this distribution during their base and build phases.
Monday: Recovery Ride • Duration: 1-2 hours • Intensity: Z1-Z2
Tuesday: Endurance Ride • Duration: 2-3 hours • Intensity: Z2
Wednesday: High-Intensity Intervals • Duration: 1.5 hours total • Structure: 5x5min @ Z5
Thursday: Endurance Ride • Duration: 2-4 hours • Intensity: Z2
Friday: Easy Spin • Duration: 1 hour • Intensity: Z1
Saturday: High-Intensity Intervals • Duration: 2 hours total • Structure: 3x20min @ Z6
Sunday: Long Endurance • Duration: 3-6 hours • Intensity: Z2
• Weekly volume: 20-30 hours during Grand Tour preparation • Distribution: 80%+ at conversational pace
• Weekly volume: 8-12 hours • Distribution: Same 80/20 principle applies
Amateur cyclists often train too hard on easy days and too easy on hard days, spending excess time in Zone 3. This 'grey zone' prevents adequate recovery while not providing enough stimulus for high-end adaptations. Polarized training fixes this.
The biggest mistake is making easy rides too hard. True Zone 2 should feel 'embarrassingly easy' - you should be able to hold a full conversation. Many riders creep into Z3 on group rides or climbs, ruining the polarization.
Pedaloom tracks TSS, power zones, and training load to help you implement these methods effectively.