Ironman Base Builder – Athlete Overview
This 12-week plan is designed for athletes aiming to build a solid aerobic foundation for an Ironman or long-distance triathlon. It’s best suited for athletes who already have a basic endurance base (able to complete workouts in the 60–90 min range) and want to systematically increase fitness while minimising injury risk.
Plan Structure:
Weekly Layout: 3 bike, 3 run, 2 swim sessions, starting each week with a recovery day
Intensity Guidance: Bike and run sessions are based on Threshold HR, swims on RPE
Weekly Volume: 7–10 hours, progressively increasing across the block
Equipment Needed:
Aside from essential swim, bike, run kit, you will need a way to track your heart rate during workouts. A heart rate strap is best, but a GPS watch with heart rate tracking will do.
Communication:
This plan is structured for self-guided use, but weekly adjustments can be made based on fatigue, HR responses, or schedule changes.
If you’re working with a coach, share session completion and HR/RPE feedback to inform future adjustments.
Who This Plan Is For:
Athletes seeking a controlled, progressive build of endurance and threshold fitness before moving into race-specific build and peak phases
Those who want a structured, repeatable framework for all three disciplines
Individuals aiming to avoid overtraining while establishing a strong aerobic base
Hi, I'm Joe – a London-based endurance coach who works with everyday athletes taking on the events that once felt impossible, specialising in first timers.
I'm ESCI (Ironman U) certified and TrainingPeaks Level 2 accredited, and what drives my coaching is seeing an athlete cross a finish line they didn't think they could reach. I've been there myself, juggling marathon and Ironman training around a full-time job in financial services, and I know exactly how hard it is to find the balance.