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Periodization

Periodization is the systematic planning of athletic training through distinct phases. Learn about training periodization, macrocycles, mesocycles, and how to structure your training year.

Quick Answer

Periodizationis the strategic division of training into specific phases (periods), each with distinct goals and training emphases. It prevents overtraining, maximizes adaptation, and peaks performance for key events.

What is Periodization?

Periodization structures training into organized phases rather than doing the same workouts year-round. Each phase builds on the previous one, leading to peak performance at target events.

The core principle: Training stress must vary to:

  • Prevent stagnation
  • Allow recovery
  • Build different fitness components
  • Peak at the right time

Training Cycles

Periodization organizes training into nested cycles:

CycleDurationPurpose
Macrocycle6-12 monthsFull training year/season
Mesocycle3-6 weeksTraining block with specific focus
Microcycle1 weekIndividual training week

Classic Periodization Phases

1. Base Phase

AspectDetail
Duration8-16 weeks
VolumeHigh
IntensityLow (Zone 2)
FocusAerobic foundation
Key workoutsLong, easy efforts

2. Build Phase

AspectDetail
Duration6-10 weeks
VolumeModerate-high
IntensityModerate-high
FocusRace-specific fitness
Key workoutsThreshold, intervals

3. Peak Phase

AspectDetail
Duration2-4 weeks
VolumeModerate
IntensityHigh
FocusSharpening, race simulation
Key workoutsRace-pace efforts

4. Taper Phase

AspectDetail
Duration1-3 weeks
VolumeReduced 40-60%
IntensityMaintained
FocusRecovery and freshness
Key workoutsShort, sharp efforts

5. Recovery Phase

AspectDetail
Duration1-4 weeks
VolumeVery low
IntensityVery low
FocusMental and physical recovery
ActivitiesCross-training, rest

Periodization Models

Linear Periodization

Progressive increase in intensity, decrease in volume:

PhaseVolumeIntensity
BaseHighLow
BuildMediumMedium
PeakLowHigh
TaperVery lowMedium-high

Best for: Single peak races, beginners.

Block Periodization

Concentrated focus on one ability per block:

BlockDurationFocus
Block 13-4 weeksEndurance
Block 23-4 weeksThreshold
Block 33-4 weeksSpeed/power

Best for: Experienced athletes, multiple races.

Reverse Periodization

Start with intensity, build volume later:

PhaseVolumeIntensity
EarlyLowHigh
MiddleMediumMedium
LateHighMedium

Best for: Time-crunched athletes, short events.

Undulating Periodization

Varying intensity within weeks:

DayFocus
MondayEasy
TuesdayHigh intensity
WednesdayEasy
ThursdayModerate
FridayRest
SaturdayLong/moderate
SundayEasy

Best for: Year-round fitness, frequent racing.

Example Annual Plan

Single-Peak Marathon Plan

PhaseWeeksFocus
Off-season4-6Recovery, cross-training
Base 16Aerobic foundation
Base 24Build volume
Build 14Add threshold work
Build 24Race-specific intensity
Peak3Race simulation
Taper2-3Recovery, freshness
Race1Race week

Volume and Intensity Across Phases

PhaseVolumeIntensityRecovery
Base100%60%High
Build80%85%Moderate
Peak60%100%Moderate
Taper40%85%Very high
Recovery30%40%Very high

Key Periodization Principles

Progressive Overload

Training stress must gradually increase for continued adaptation.

Specificity

Training should become more race-specific as events approach.

Variation

Avoid monotony by varying workouts within and between phases.

Recovery

Rest is where adaptation occurs—include adequate recovery.

Individualization

Respond to your body; no plan is perfect as written.

Periodization for Different Goals

Endurance Events (Marathon, Ironman)

  • Long base phase: 12-16 weeks
  • Extended build: 8-12 weeks
  • Longer taper: 2-3 weeks

Speed Events (5K, Criteriums)

  • Shorter base: 6-8 weeks
  • More intensity phases: Multiple speed blocks
  • Shorter taper: 1-2 weeks

Year-Round Racing

  • Block periodization: Focus areas rotate
  • Mini-tapers: Before key races
  • Continuous base maintenance

Common Questions

How do I know which phase I should be in?

Count backward from your key race:

  • Taper: 1-3 weeks before race
  • Peak: 3-6 weeks before race
  • Build: 6-14 weeks before race
  • Base: 14+ weeks before race

Can I skip the base phase?

Not recommended. Base fitness supports all other training. Skipping it leads to:

What if I have multiple key races?

Options:

  • Block periodization with mini-peaks
  • Choose a primary race and accept others as training
  • Double or triple periodization (more complex)

How do I adjust if I miss training?

  • 1-3 days missed: Continue as planned
  • 1 week missed: Repeat current week
  • 2+ weeks missed: Reassess phase length

Disclaimer: Information provided by this site is for educational purposes only and is not intended to be a substitute for professional medical advice specific to the reader's particular situation. The information is not to be used for diagnosing or treating any health concerns you may have. The reader is advised to seek prompt professional medical advice from a doctor or other healthcare practitioner about any health question, symptom, treatment, disease, or medical condition.