Ironman Training: Complete Guide to 140.6
The Ironman triathlon is the ultimate test of endurance: 2.4-mile swim, 112-mile bike, and 26.2-mile run. This guide covers everything you need to prepare for and complete 140.6 miles.
My First Ironman Journey
Follow my documented path to Challenge Roth 2026 with training logs, coaching insights, and lessons learned.
Read the Journey →The Six Training Phases
Ironman preparation typically spans 20-30 weeks and follows six distinct phases:
1. Base Phase (8-12 weeks)
Aerobic foundation building through zone 2 training. Focus on technique and consistency.
2. Build Phase (6-8 weeks)
Increasing intensity and race-specific work. Threshold training and brick workouts.
3. Peak Phase (2-3 weeks)
Highest training load. Longest bike (5-6 hours) and run (2.5-3 hours) sessions.
4. Taper Phase (2-3 weeks)
Reducing volume 40-60% while maintaining intensity. Trust the process.
5. Race Week
Final preparation, equipment check, course familiarization, and execution.
6. Transition/Recovery (2-4 weeks)
Post-race recovery and regeneration before your next training block.
Base Phase: Building Your Foundation
The base phase is the most important—and often most overlooked—period of Ironman training. This is where you develop the aerobic engine that will carry you through 140.6 miles.
Key Objectives
- Build aerobic capacity through zone 2 training (60-75% max HR)
- Develop muscular endurance for swim, bike, and run
- Establish consistent training habits and volume
- Work on technique in all three disciplines
- Address limiters and weaknesses
Typical Weekly Structure
- Swim: 3-4 sessions, focus on technique and endurance
- Bike: 3-4 rides including one long ride (3-4 hours)
- Run: 3-4 runs including one long run (90-120 min)
- Strength: 2 sessions for injury prevention
Build Phase: Race-Specific Training
The build phase introduces race-specific intensity while continuing to increase volume. This is where you start simulating race conditions.
Key Objectives
- Introduce threshold and tempo work
- Practice race-day nutrition strategy
- Complete brick workouts (bike-to-run transitions)
- Build mental resilience through longer sessions
- Fine-tune pacing for race intensity
Peak Phase: Maximum Training Load
The peak phase represents your highest training volume and intensity. You should complete your longest training sessions during this period.
Key Workouts
- Longest bike: 5-6 hours at race pace
- Longest run: 2.5-3 hours
- Race simulation: Full nutrition and pacing rehearsal
- Open water swimming practice
Taper Phase: Sharpening for Race Day
The taper reduces training volume by 40-60% while maintaining some intensity. This allows your body to absorb the training and arrive at the start line fresh.
Taper Guidelines
- Reduce volume progressively (not all at once)
- Maintain 1-2 quality sessions per week
- Focus on sleep and recovery
- Finalize equipment and logistics
- Trust the process—fitness is banked
Race Week: Final Preparation
Race week is about staying calm, staying healthy, and executing your plan.
Race Week Checklist
- Light activation workouts only
- Hydrate and fuel properly
- Attend athlete briefing and course familiarization
- Check in gear and set up transition
- Visualize your race and review your plan
Transition/Recovery: Post-Race Regeneration
After crossing the finish line, your body needs time to recover from the immense stress of racing 140.6 miles.
Recovery Timeline
- Week 1: Complete rest or very light activity
- Week 2: Easy swimming and walking
- Week 3: Short, easy sessions in all disciplines
- Week 4: Return to structured training
Key Periodization Principles
- Progressive Overload: Gradually increase training stress over time
- Specificity: Training should mimic race demands
- Recovery: Adaptation happens during rest, not during training
- Individualization: Adjust phases based on your fitness level and goals
- Consistency: Regular training beats sporadic heroic efforts