70.3 triathlon training
Half-distance triathlon (70.3) training plan
A half-distance triathlon is a 1.9 km swim, a 90 km bike and a 21.1 km run, often called a 70.3 for the total miles. It takes five to seven hours for most age-groupers, which makes it an aerobic, pacing and fuelling event far more than a test of top speed.
- Distances
- 1.9 km swim · 90 km bike · 21.1 km run
- Typical build
- 16 to 24 weeks
- Peak weekly time
- 8 to 12 hours
- Taper
- 10 to 14 days
How a 70.3 plan is structured
Most athletes need 16 to 24 weeks, built in base, build and race-specific phases followed by a taper. A typical week has three swims, three rides and three runs, with the long ride on one weekend day and the long run on the other. Weekly hours grow gradually to a peak of about 8 to 12, with a lighter week every three or four. About 80 percent of the training is easy aerobic work.
The bike is where the race is decided
The bike is about half the race time, and how you ride it sets up the run. Long rides build to 3 to 4 hours, including blocks at race effort. If you train with power, most age-groupers race at roughly 70 to 80 percent of FTP; a sweet spot session such as 3 × 15 minutes at 88 to 94 percent of FTP builds the strength to hold it. Riding too hard is the most common way to ruin the half marathon that follows.
Bricks and the long run
Weekly bricks teach you to run well off the bike: a long ride followed by a 20 to 40 minute run at goal effort. The standalone long run builds to about 1 hour 45 minutes to 2 hours; running much longer adds injury risk without much gain, because the bike volume is already building your endurance. Keep at least one easy day between hard run sessions.
Swim with a pace, not just yards
Test your critical swim speed with a 400 m and a 200 m time trial and train around it: sets like 10 × 100 m at CSS pace with 15 seconds rest build the sustainable speed a 1.9 km swim needs. Add open-water sessions with sighting in the final two months. Most athletes gain more on the swim from technique and consistency than from extra distance.
Fuelling and the taper
Five-plus hours of racing needs a plan: most athletes aim for 60 to 90 grams of carbohydrate per hour on the bike and keep taking some on the run, plus fluid and sodium matched to the heat. Practise it on every long ride and brick. Taper over 10 to 14 days, reducing volume by around 40 to 60 percent while keeping short race-effort blocks in each sport.
A sample week
A build-phase week of about 9 to 10 hours. With less time, keep the long ride, the brick run, the long run and two swims.
- Mon
- Swim, 45 min: 10 × 100 m at CSS pace, 15 s rest
- Tue
- Bike, 60 min: 3 × 12 min sweet spot (88 to 94 percent FTP), 5 min easy between
- Wed
- Run, 50 min: 3 × 8 min at half marathon effort, 2 min easy between
- Thu
- Swim, 45 min technique and aerobic, open water if possible
- Fri
- Rest or easy 30 min spin
- Sat
- Brick: 3 h ride with 2 × 30 min at race effort, then 25 min run at goal effort
- Sun
- Long run, 1 h 30 min easy; short easy swim if time allows
The mistake that wrecks most 70.3 runs
Riding the bike to feel good about the bike split. Ten extra watts for 90 kilometres often costs fifteen minutes on the half marathon. Ride to a planned effort, eat on schedule from the first 15 minutes, and let the run be where you pass people.
Common questions
How long does it take to train for a 70.3?
Sixteen to twenty-four weeks for most age-groupers, assuming you can already swim continuously and have some cycling and running background. A sprint or Olympic race first is a sensible step.
How many hours a week do I need for a half-distance triathlon?
Most athletes peak at 8 to 12 hours a week. Finishing is possible on less if the time goes to the long ride, the long run and consistent swimming.
What does 70.3 mean?
It is the total race distance in miles: 1.2 mile swim, 56 mile bike and 13.1 mile run. Many events of this distance use other names, such as half-distance or middle-distance triathlon.
Is the AthleteSpace 70.3 plan free?
Yes. The plan, the coach and the analytics are free with no credit card, and the plan rebalances when you miss a session or have a heavy week.