# Phase 06 — Intelligent Workout Adaptation & Recovery Tracking

## 🎯 Goals
Skapa intelligenta träningsprogram som anpassas baserat på muskelgruppernas återhämtning, inte bara vilket pass som kördes senast.

## 📋 Features

### 06-01: Workout Swap/Rotation System
- [ ] Add "Swap Workout" button to WorkoutPage
- [ ] Show available workouts for current week
- [ ] Replace current workout while keeping tracking
- [ ] Update UI to show swap history
- [ ] Database: Update workout_logs to track swaps

### 06-02: Muscle Group Recovery Tracking
- [ ] Model: Define muscle groups per exercise
- [ ] Calculate recovery time from last workout targeting each group
- [ ] Store: muscle_group_recovery table (timestamp, intensity)
- [ ] Display: Recovery status in ExerciseCard (red/yellow/green)
- [ ] Algorithm: Track last 7-14 days of activity per muscle group

### 06-03: Smart Workout Recommendation Engine
- [ ] Analyze: Which muscle groups were trained this week
- [ ] Identify: Most-recovered groups available to train today
- [ ] Suggest: 2-3 workouts that target recovered muscle groups
- [ ] Avoid: Overtraining same groups (48-72h rest recommendation)
- [ ] Backend: POST /api/recommendations/smart-workout

### 06-04: Recovery Metrics & Analytics
- [ ] Dashboard card: Recovery status per muscle group
- [ ] Chart: 7-day muscle group activity heatmap
- [ ] Insight: "Chest needs work", "Legs well-recovered"
- [ ] Prediction: Next recommended workout based on recovery

### 06-05: UI/UX Polish
- [ ] Integrate swap system with recommendation engine
- [ ] Show recovery timeline for each group
- [ ] Mobile-friendly recovery badges
- [ ] One-tap "Use Recommendation" button
- [ ] Visual feedback for muscle group selection

### 06-06: Testing & Validation
- [ ] E2E tests: Swap workflow
- [ ] E2E tests: Recovery calculation accuracy
- [ ] Performance: Recovery algorithm benchmarks
- [ ] User feedback: Recommendation quality validation

## 🏗️ Database Changes
```sql
-- Muscle Group Recovery Tracking
CREATE TABLE muscle_group_recovery (
  id SERIAL PRIMARY KEY,
  user_id INTEGER REFERENCES users(id),
  muscle_group VARCHAR(50),
  last_workout_date TIMESTAMP,
  intensity FLOAT, -- 0-1
  exercises_count INT,
  created_at TIMESTAMP DEFAULT NOW()
);

-- Workout Swaps
ALTER TABLE workout_logs ADD COLUMN swapped_from_id INT REFERENCES workout_logs(id);
```

## 🔑 Key Algorithms

### Recovery Calculation
```
recovery_score = 1.0 if last_workout > 72h ago
recovery_score = 0.5 if 48h < last_workout < 72h
recovery_score = 0.2 if 24h < last_workout < 48h
recovery_score = 0.0 if last_workout < 24h
```

### Smart Recommendation
1. Get all exercises available
2. Group by muscle group
3. Calculate recovery for each group
4. Sort by recovery score (highest = best to train)
5. Filter: exclude groups with score < 0.3
6. Return: Top 3 workouts with best muscle group coverage

## 📦 Implementation Order
1. **06-01** — Basic swap functionality (UI + backend)
2. **06-02** — Recovery tracking (database + calculations)
3. **06-03** — Recommendation engine (backend algorithm)
4. **06-04** — Analytics & visualization (frontend)
5. **06-05** — Polish & integration
6. **06-06** — Testing

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