Half distance guide

The half distance — 1.9km swim, 90km bike, 21.1km run — is branded as Ironman 70.3 in the Ironman series. It represents a significant step up in endurance, time commitment, and race strategy.

This is where triathlon becomes a lifestyle. Training weeks regularly exceed 8 hours, and the race itself lasts 5-7 hours for most age-groupers.

If you've completed a sprint or Olympic distance and want a bigger challenge, half distance is the natural progression. You should be comfortable training 8-12 hours per week and have 16-20 weeks to prepare.

Half distance is often cited as the most satisfying triathlon distance — long enough to feel like a major achievement without the extreme commitment of full distance.

Training builds in phases: Base (4-6 weeks of aerobic foundation), Build (6-8 weeks adding intensity and volume), Peak (2-3 weeks of race-specific work), and Taper (1-2 weeks reducing volume).

Long bike rides should reach 3-4 hours. Long runs should reach 90 minutes-2 hours. Include at least one brick per week with extended run portions.

Strength training and mobility work are non-negotiable at this volume.

Plan to consume 60-80g of carbohydrates per hour on the bike and 40-60g on the run. This means eating every 20-30 minutes.

Practice your exact race nutrition plan during 3-4 long training sessions before race day. Use the same brands, quantities, and timing.

Hydration: 500-750ml per hour with electrolytes. Know your sweat rate.

Swim: Sight well, draft when possible, exit calmly.

Bike: This is where the race is won or lost. Ride steady, eat religiously, and resist the urge to chase faster riders. Target 70-75% of FTP.

Run: Start 30 seconds per km slower than your standalone half marathon pace. Walk through aid stations. Pick it up in the final 5km if you have energy.

Mental strategy: Break the race into segments. Don't think about the run while on the bike.