| name | cycling-training |
| description | Cycling training plans, power zones, FTP testing, intervals, periodization, indoor/outdoor training, race preparation, training-load analysis, and recovery guidance. Use when Codex needs to design cycling workouts, calculate FTP-based zones or TSS, analyze training data, manage CTL/ATL/TSB, or answer cyclist training questions. |
Cycling Training Skill
Evidence-based cycling training guidance grounded in peer-reviewed sports science research.
Quick Reference
Power Zones (Quick Reference)
| Zone | Name | % FTP | Primary Use |
|---|
| 1 | Active Recovery | <55% | Recovery rides |
| 2 | Endurance | 55-75% | Aerobic base |
| 3 | Tempo | 76-90% | Muscular endurance |
| 4 | Threshold | 91-105% | FTP development |
| 5 | VO2max | 106-120% | Aerobic capacity |
| 6 | Anaerobic | 121-150% | AC intervals |
| 7 | Neuromuscular | Max | Sprints |
For detailed zone models (Seiler 3-zone, iLevels, HR zones, Training Intensity Distribution), see zones-and-testing.md
Scripts (Quick Reference)
If this skill is installed locally, set SKILLS_DIR to the directory your tool uses for skills.
SKILLS_DIR="<path-to-your-skills-dir>"
python3 "$SKILLS_DIR/cycling-training/scripts/calculate_zones.py" 250 --model coggan
python3 "$SKILLS_DIR/cycling-training/scripts/calculate_zones.py" 250 --model seiler --json
python3 "$SKILLS_DIR/cycling-training/scripts/calculate_tss.py" 250 230 60 --json
python3 "$SKILLS_DIR/cycling-training/scripts/analyze_week.py" 450 65 72 --prev-week-tss 400 --daily-tss 60,80,0,70,90,80,70 --json
Test suite (stdlib only):
python3 -m unittest discover -s "$SKILLS_DIR/cycling-training/scripts/tests" -p 'test_*.py' -v
Companion Skills
intervals-icu (Data API)
For fetching and updating data from intervals.icu platform, use the intervals-icu skill:
┌─────────────────┐ fetch data ┌───────────────────┐
│ intervals-icu │ ──────────────────► │ cycling-training │
│ (DATA API) │ │ (ANALYSIS) │
│ │ ◄────────────────── │ │
│ • wellness │ interpret results │ • zone calc │
│ • activities │ │ • periodization │
│ • power curves │ │ • workout design │
│ • fitness │ │ • load management │
└─────────────────┘ └───────────────────┘
Common workflow:
- Fetch data:
$SKILLS_DIR/intervals-icu/scripts/api.sh wellness today
- Analyze with this skill (zone calculation, load management)
- Update:
$SKILLS_DIR/intervals-icu/scripts/api.sh wellness-update today '{"readiness": 4}'
Indoor Training Essentials
Critical Setup:
| Component | Requirement | Why |
|---|
| Fan | Strong airflow at torso (as much as practical) | Better cooling and higher sustainable indoor power |
| Temperature | <20°C (68°F) | Prevents overheating |
| FTP | Test indoors separately | 5-10% lower than outdoor |
Indoor FTP Adjustment:
- Use 95% of outdoor FTP OR
- Perform dedicated indoor FTP test (recommended)
- TrainerRoad AI FTP Detection can be a useful estimate; validate with workouts/tests
ERG vs Slope Mode:
| Mode | Use When | Benefit |
|---|
| ERG | Structured intervals | Holds exact power target |
| Slope | Race simulation, cadence drills | Natural power fluctuations |
For complete indoor setup guide, see indoor-training.md
Indoor Workout Quick Examples
Sweet Spot (ERG Mode):
Warm-up: 10 min @ 55% FTP
Main: 2×20 min @ 88-92% FTP (5 min recovery)
Cool-down: 10 min easy
Total: 65 min | TSS: ~70
TrainerRoad: Carson, Geiger
Zwift: SST (Short) or custom
VO2max Intervals (ERG Mode):
Warm-up: 15 min progressive to 75% FTP
Main: 5×4 min @ 108-112% FTP (4 min @ 50% recovery)
Cool-down: 10 min easy
Total: 65 min | TSS: ~85
TrainerRoad: Baird, Spencer
Zwift: The Gorby or custom
Threshold (Slope Mode for pacing practice):
Warm-up: 15 min with 2×1 min @ 100%
Main: 2×15 min @ 95-100% FTP (8 min recovery)
Cool-down: 10 min easy
Total: 70 min | TSS: ~80
TrainerRoad: Kaweah, Darwin
Weekly Training Load Guidelines
| Level | Hours/Week | Weekly TSS | CTL Target |
|---|
| Recreational | 5-8 | 300-500 | 40-60 |
| Enthusiast | 8-12 | 500-700 | 60-80 |
| Competitive | 12-18 | 700-1000 | 80-100 |
| Elite Amateur | 18-25 | 1000-1400 | 100-130 |
| Professional | 25-35 | 1400-2000+ | 130-160 |
Key Metrics Formulas
TSS = (Duration_sec × NP × IF) / (FTP × 3600) × 100
IF = NP / FTP
VI = NP / AP
CTL = 42-day exponentially weighted average of TSS
ATL = 7-day exponentially weighted average of TSS
TSB = CTL - ATL
ACWR = ATL / CTL (heuristic range often cited: ~0.8-1.3)
ACWR note: ACWR is widely used, but it is also debated in the literature. Treat it as a heuristic and combine it with context (sleep, illness, soreness, performance trends), not as a single decision signal.
Race Day TSB Targets
| Event Type | Optimal TSB |
|---|
| Training race | -10 to +5 |
| B race | +5 to +15 |
| A race | +15 to +25 |
| Grand Tour stage | +5 to +15 |
Plan Templates
Ready-to-use training plan templates:
Using Templates
- Copy template to user's planning location
- Replace
[YOUR_FTP] with athlete's current FTP
- Replace
[YOUR_CTL] with current CTL
- Adjust dates and weekly structure
- Scale TSS targets based on current fitness (×0.8 for less, ×1.2 for more)
Reference Files
Load these based on specific need:
| Topic | File | Load When |
|---|
| Power zones & FTP testing | zones-and-testing.md | Setting zones, FTP tests, CP model |
| Workout library | workouts.md | Prescribing specific intervals |
| Periodization | periodization.md | Planning phases, blocks, mesocycles |
| Indoor training | indoor-training.md | Trainer setup, heat, Zwift/TrainerRoad |
| Outdoor training | outdoor-training.md | Outdoor execution, terrain, groups, safety |
| Nutrition & recovery | nutrition-recovery.md | Fueling, supplements, sleep, recovery |
| Physiology | physiology.md | VO2max, lactate, CP, efficiency |
| Strength training | strength.md | Gym work integration for cyclists |
| Special populations | special-populations.md | Masters, women, beginners, time-crunched |
| Analytics | analytics.md | Metrics, training load, data analysis |
| Training platforms | platforms.md | TrainerRoad, Zwift, intervals.icu, WKO5 comparison |
| Environmental | environmental.md | Heat acclimation, altitude training |
| Psychology | psychology.md | Motivation, mental training, indoor strategies |
| Bike fit & position | bike-fit.md | Position setup, indoor adjustments, pain issues |
| Injuries & prevention | injuries.md | Pain diagnosis, prevention, return protocols |
| Cardiovascular risks | injuries.md#cardiovascular-risks | High-volume training concerns, screening |
| Racing tactics | racing-tactics.md | Race strategy, pacing, drafting, criteriums |
| Equipment & gear | equipment.md | Trainer, fan, power meter recommendations |
| Quick reference | quick-reference.md | Common scenarios, metrics, race TSB targets |
Core Workflows
1. Creating a Training Plan
1. ASSESS current state
- Recent FTP test (within 4-6 weeks)
- Current CTL and training history
- Power duration curve / phenotype
- Available training time
- Health/injury status
2. DEFINE goals
- Target event(s) with dates
- Performance goals (power targets, placing)
- Priority (A/B/C races)
3. SELECT periodization model
- Block: For experienced cyclists, 1-3 peak events
- Traditional: For beginners, year-round racing
- Reverse: For masters, late-season peaks, indoor season
4. MAP phases backward from A event
- Race/Peak: 1-2 weeks (taper)
- Build: 6-8 weeks (race-specific intensity)
- Base: 8-12 weeks (volume, aerobic development)
5. STRUCTURE mesocycles (3-4 weeks each)
- 3:1 or 2:1 load:recovery ratio
- Progressive overload within mesocycle
- Deload week at end
6. PLAN microcycles (weekly)
- Key workouts placed optimally
- Recovery days after hard sessions
- Long ride placement (weekend typically)
7. SET targets
- Weekly TSS targets
- CTL progression (3-7 pts/week max)
- Specific workout targets
2. Analyzing Training Data
1. SESSION level
- Compare NP/IF to prescription
- Time in target zones
- HR:power decoupling (<5% = good aerobic fitness)
- Variability Index (race: 1.0-1.05, crit: 1.1+)
2. WEEKLY level
- Total TSS vs target
- Intensity distribution (TID)
- ACWR (heuristic; avoid sharp spikes)
3. BLOCK/PHASE level
- CTL trend
- FTP progression
- Power duration curve changes
- Identify limiters
4. WARNING signs
- HR elevated for given power
- Performance plateau/decline
- Elevated resting HR
- Sleep disturbance
- Mood changes
3. Prescribing Workouts
1. IDENTIFY training goal
- Aerobic base → Endurance, Tempo
- Threshold development → Sweet Spot, Threshold
- VO2max → Short/Long VO2max intervals
- Anaerobic → AC intervals, sprints
- Race-specific → Simulation workouts
2. SELECT workout type from references/workouts.md
3. ADJUST for athlete
- Scale duration/reps for fitness level
- Consider current fatigue (TSB)
- Account for weekly context
4. PROVIDE execution guidance
- Warm-up protocol
- Target power/HR
- Pacing strategy
- Recovery between intervals
- Cool-down
Key Evidence-Based Principles
Polarized Training (Seiler Research)
- 80% of training time below LT1 (easy)
- <5% between LT1-LT2 (minimize "grey zone")
- 15-20% above LT2 (hard intervals)
- Superior to threshold-heavy approaches for trained athletes
- Exception: Time-crunched athletes may benefit from more sweet spot
Progressive Overload
- CTL increase: 3-7 points/week (max 10 aggressive)
- Volume increase: 5-10% per week maximum
- Ramp rate = (CTL_target - CTL_current) / weeks_available
- Always follow 2-3 hard weeks with recovery week
Recovery Integration
- Deload every 3-4 weeks (40-60% volume cut)
- Maintain some intensity during deloads
- Sleep: 8-9 hours optimal for adaptation
- Nutrition timing: Protein within 2h, carbs for glycogen
Supercompensation Timing
| Adaptation | Recovery Time |
|---|
| Neuromuscular | 24-72 hours |
| Glycogen stores | 24-48 hours |
| Aerobic enzymes | 7-14 days |
| Structural (muscle) | 3-6 weeks |
Indoor vs Outdoor Training
- Power typically 5-10% lower indoors
- RPE higher for same power output
- Cooling critical: Fan essential, room temp <20°C
- Heat stress can be used for heat adaptation
- ERG mode for structured intervals
- Slope mode for race simulation / pacing practice
Overtraining Prevention
Monitor daily:
- Morning resting HR (+5 bpm = warning)
- HRV trend (decreasing = accumulating fatigue)
- Sleep quality
- Subjective wellness (1-10 scale)
Red flags:
- Performance decline despite adequate training
- Persistent fatigue >2 weeks
- Illness frequency increase
- Mood disturbances
Cardiovascular Risks (High Volume)
Medical disclaimer: Educational only — not medical advice. If you have symptoms or risk factors, seek medical evaluation.
Red flags to take seriously:
- Palpitations, unusual dyspnea, syncope, chest pain
→ See injuries.md for details and sources
Workflow Guides
Plan Type Decision Tree
Athlete's primary goal?
├── Build aerobic base
│ └── Use: Base Building workflow → base-8-week.md template
├── Increase FTP/threshold
│ └── Current CTL?
│ ├── <60: Build base first (4-6 weeks)
│ └── ≥60: Use Build workflow → FTP focus
├── Prepare for specific event
│ └── Weeks until event?
│ ├── >12 weeks: Full periodization (base → build → peak)
│ ├── 8-12 weeks: Build → peak
│ └── <8 weeks: Maintenance + race specificity
└── Indoor winter training
└── Use: indoor-season.md template
Intensity Distribution Decision
Available training hours/week?
├── <6 hours
│ └── Polarized approach: 80% Z1-2, 20% Z5+
│ (Skip Z3-4, maximize recovery between intensity)
├── 6-10 hours
│ └── Pyramidal approach: 75% Z1-2, 15% Z3-4, 10% Z5+
└── >10 hours
└── Traditional periodization or pyramidal
(More flexibility in distribution)
Training Analysis Workflow
When analyzing completed training data:
-
Weekly Review
- Compare actual vs planned TSS
- Check intensity distribution (time in zones)
- Review key workout execution (hit targets?)
- Note subjective feedback (RPE, fatigue, mood)
-
Performance Trends
- Track FTP progression (eFTP from intervals.icu)
- Monitor Efficiency Factor (NP/HR) trend
- Check power curve for improvements
- Compare HR:power decoupling on endurance rides
-
Load Management
- Calculate ACWR (heuristic; watch for spikes)
- Monitor CTL ramp rate (<7 pts/week)
- Watch for excessive negative TSB (<-30)
-
Red Flags to Address
- Declining power at same HR
- Increasing RPE for same workouts
- Poor sleep/recovery scores
- Missed workouts pattern
→ For detailed metrics, see analytics.md
Common Scenarios
Quick answers with deep-dive links: See quick-reference.md
