# Coaching Principles

The training philosophy underlying all coaching decisions, based on
Joe Friel ("The Cyclist's Training Bible", "Fast After 50").

This is the conceptual foundation — the WHY. Concrete thresholds live in
interpretation-rules.md, planning actions in decision-process.md, zone
definitions in training-zones.md, and goal-specific emphasis in the
athlete/discipline block.

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## Core Principles

- **Specificity** — training becomes more event-specific as the target
  approaches; early phases build general fitness, later phases the event's
  specific demands.
- **Progressive Overload** — fitness improves through gradual increases in
  training stress, followed by recovery that allows adaptation.
- **Consistency** — long-term consistency matters more than short-term
  intensity; avoid large swings in load.
- **Individualization** — account for age, recovery ability, limiter
  profile, and available training time.

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## Periodization

### Structure
- **Macrocycle** — the full season, aligned to key events (A races / goals).
- **Mesocycle** — typically 3 weeks progressive load + 1 recovery week.
  For athletes 50+: 2 weeks load + 1 recovery week.
- **Microcycle** — the weekly structure. The coach operates primarily at
  this level; mesocycles are usually defined externally.

### External Planning Systems (IMPORTANT)
When a structured plan is provided (e.g. from intervals.icu):
- use its phases (Base, Build, Peak, Transition) and weekly load (TSS) targets
- respect and follow it whenever available

It is NOT mandatory: if missing, inconsistent, or clearly inappropriate,
apply standard Friel-based periodization instead.

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## Training Phases (concept)

- **Base** — aerobic endurance, efficiency, basic strength.
- **Build** — develop FTP and VO2max, muscular endurance.
- **Peak** — race-specific performance, sharpened intensity, reduced volume.
- **Transition** — recovery, mental reset, maintain basic fitness.

(What to schedule in each phase is defined in decision-process.md.)

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## Intensity Distribution

### 80/20 Principle
~80% low intensity (Z1–Z2), ~20% moderate to high — to maximize adaptation
while minimizing fatigue accumulation.

### Distribution Models
- **Base** — predominantly low intensity
- **Pyramidal** — majority low, some threshold, little high intensity
- **Polarized** — high low-intensity volume + some high intensity, minimal threshold
- **Threshold-heavy** — larger proportion in Z3–Z4

The appropriate model depends on phase, limiter, and fatigue.

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## Key Performance Factors

- **Aerobic Endurance** — the foundation of all performance; built through
  long, steady rides.
- **Threshold (FTP)** — sustained power; critical for long climbs.
- **VO2max** — maximal aerobic capacity; supports FTP development.
- **Aerobic Durability** — holding power over long durations.
- **Fueling** — directly affects endurance and durability; insufficient
  fueling can mimic a fitness limitation.

Training prioritizes the athlete's primary limiter. (Detection is in
interpretation-rules.md; the resulting action in decision-process.md.)

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## Training Load (concept)

Training load (TSS) combines duration and intensity.
Reference: 1 hour at FTP ≈ 100 TSS.
Used to manage weekly load and to track fitness (CTL), fatigue (ATL), and
form (CTL − ATL). (Form interpretation thresholds: interpretation-rules.md.)

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## Recovery and Adaptation

Adaptation occurs during recovery, not during training.
Recovery indicators: HRV, resting heart rate, subjective fatigue.
- include regular recovery weeks
- reduce load when fatigue is high
- prioritize sleep and nutrition

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## Age-Specific Considerations (50+)

- reduced recovery capacity → protect recovery
- intensity maintenance becomes more important
- VO2max must be trained year-round to slow its decline
- shorter build cycles are preferable

(The concrete "1 VO2max session every week" rule is in decision-process.md.)

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## Key Principle

Every training decision balances stress (load) against recovery
(adaptation capacity): apply enough stress to stimulate adaptation without
exceeding the athlete's ability to recover.
