Training Plan for a Half Ironman Event


Author’s Note: This is a general training plan, not specific, for a 70.3 Ironman triathlon. Please consult with a coach or medical professional before starting any training program.

The 70.3 Ironman, also known as the Half Ironman, is a challenging endurance event that consists of a 1.2-mile (1.9 km) swim, a 56-mile (90 km) bike ride, and a 13.1-mile (21.1 km) run. To successfully complete this race, you’ll need a well-structured training plan that builds your endurance, strength, and technique across all three disciplines.

Since so many of you are training for a half-distance race with the new Ironman New York around the corner, I thought this would be helpful.

Training Plan Overview:

Duration: 20 weeks

Weekly Structure: 3 swims, 3 bike rides, 3 runs, 1-2 strength session, and 1 rest day

Longest workouts: 1.2-mile swim, 60-mile bike ride, and 14-mile run

Weeks 1-4: Building a Base

During the first four weeks, focus on building a solid foundation in each discipline. Start with shorter distances and gradually increase your training volume.


Begin with 30-minute sessions and gradually increase to 45 minutes. Focus on technique and form.


Start with rides of 30-45 minutes and gradually build up to 1.5-hour sessions.


Begin with 30-minute runs and work up to 45 minutes. Maintain an easy pace to build endurance.


Incorporate one full-body strength training session per week, focusing on functional exercises for triathletes.

Weeks 5-12: Building Endurance and Speed

In this phase, you’ll continue to increase your training volume while also incorporating speed and interval workouts.


Increase your swim sessions to 60 minutes, including some interval training and open water swims (if possible).


Gradually extend your rides to 3 hours, incorporating hill training and interval sessions.


Build up to 1.5-hour runs, including some faster-paced intervals or tempo runs.


Continue with weekly strength workouts, focusing on core stability and functional exercises.

Weeks 13-16: Race Specificity and Brick Workouts

As race day approaches, it’s essential to prepare your body for the specific demands of the 70.3 Ironman. This phase includes brick workouts—back-to-back bike and run sessions—to simulate race conditions.


Maintain at least 60-90-minute sessions, focusing on pacing and open water skills.


Build up to 4-hour rides, but also include brick workouts with a 45-60 minute run immediately after a bike session.


Maintain 1.5-hour runs, but focus on pacing and include some race-specific brick workouts.


Maintain weekly strength sessions, but consider reducing the intensity as training volume increases.

Weeks 17-20: Taper and Race

During the final weeks, you’ll taper your training volume to ensure that your body is well-rested and ready for the race.


Reduce swim sessions to 30-45 minutes, focusing on technique and form.


Gradually decrease ride duration, with your last long ride two weeks before the race.


Reduce run duration to 30-45 minutes, maintaining an easy pace.


Limit strength training to one or two low-intensity sessions per week.


In the final two weeks, significantly reduce your training volume while maintaining some shorter, high-intensity workouts.

With dedication and consistent training, you’ll be prepared to tackle your 70.3 Ironman triathlon. Remember to listen to your body, adjust the plan as needed, and consult a professional for personalized guidance.

This 20-week training plan is designed to help you gradually progress toward your 70.3 Ironman goal while minimizing the risk of injury. It’s a general plan but not specific to any particular athlete. If you want a specific plan, please reach out to me and I can help you with one.

Happy training!