| Factor | Ironman (140.6) | 70.3 (Half Ironman) |
|---|---|---|
| Swim | 3.86km | 1.9km |
| Bike | 180km | 90km |
| Run | 42.2km (full marathon) | 21.1km (half marathon) |
| Typical time | 8-17+ hours | 4-8 hours |
| Training (peak wk) | 20-25+ hours | 12-18 hours |
| Recovery | 2-4 weeks | 1-2 weeks |
| Cost | Very high (entry + travel) | High |
Choose Ironman (140.6) when…
You want the ultimate single-day endurance challenge, are ready to commit 15-20+ hours per week of training, have completed 70.3 distance and want more, or want to qualify for the Ironman World Championship in Hawaii.
Choose 70.3 (Half Ironman) when…
You're new to long-course triathlon, want to race multiple times per year, are building toward a full Ironman, want a significant challenge with 10-15 hours per week training, or prefer a more manageable recovery time.
Gear for both
Cervelo P2 Triathlon Bike
Entry-level TT bike for 70.3 and Ironman time trial bike legs.
Check price on AmazonIronman Training Plan (Book)
Periodised Ironman and 70.3 training plans with weekly structure.
Check price on AmazonAs an Amazon Associate we earn from qualifying purchases.
FAQ
How many 70.3s before attempting a full Ironman?
Most coaches recommend completing 2-3 strong 70.3 races before entering a full Ironman. This builds race experience, nutrition strategy knowledge and confidence that the full distance isn't just 'twice as hard'.
How long does it take to train for a Half Ironman (70.3)?
Most training plans for a 70.3 run 12–20 weeks, with peak training weeks reaching 10–14 hours of swim/bike/run combined. For athletes with a solid base in all three disciplines, 16 weeks is a typical preparation period. Athletes new to triathlon or one of the disciplines may need 6–12 months of base building before starting a formal 70.3 plan.
What is the cut-off time for an Ironman?
The standard Ironman (140.6) cut-off time is 17 hours from the start. Individual leg cut-offs typically apply: swim closes at 2 hours 20 minutes, bike closes at 10 hours 30 minutes from race start, and the run/finish line closes at 17 hours. The Ironman 70.3 cut-off is typically 8 hours 30 minutes. Athletes who miss a cut-off are removed from the course — finishing a triathlon within the cut-off is the primary goal for many first-timers.