How to Train for a Full-Distance Triathlon

A full-distance triathlon (3.8 km swim, 180 km bike, 42.2 km run) is the ultimate test of endurance and consistency. Around twenty-one to twenty-three weeks of structured training, built on an existing base, gives most athletes the time to prepare well.

Consistency beats heroics

Weeks of steady, mostly easy training build the durability you need. Avoid big single weeks that leave you tired for the next fortnight.

Long rides and runs

Build the long ride towards five to six hours and the long run towards 2 h 30 to 3 h, keeping both largely aerobic. Some long rides should include race-pace blocks.

Nutrition

Fuelling is the fourth discipline. Use every long session to rehearse your race-day intake of carbohydrate, fluid and sodium.

Taper

A two- to three-week taper reduces fatigue while keeping you sharp. Trust the work you have done.

Ready to start?

The Endurance Lab full-distance triathlon training plans come in four levels (Start, Develop, Perform and Podium). Choose heart rate or power on the bike, and heart rate, pace or power on the run. Use Find your plan to filter by level, the hours you have each week and the weeks until your race. New to training by effort? Read our RPE guide and training zones guide first.

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Next step

Measure it in the lab

Book a VO2max or lactate test in Dún Laoghaire and get your results explained in plain language.

Next step

Train with a plan built on your data

Personalised TrainingPeaks coaching — remote, or with the EL Squad in Dublin.

Next step

Know your numbers

Measure your body composition and resting metabolic rate to plan fuelling with real data.

Next step

Book a recovery appointment

Sports massage, neuromuscular therapy and Reiki in Dún Laoghaire — book and pay online.

Next step

See where you stand

A healthspan assessment turns fitness and healthy-ageing markers into practical next steps.

Next step

Race with a plan

Set accurate zones in the lab and prepare with a coach who plans your pacing.

Next step

Train with the EL Squad

Group S&C, a weekly track session and Sunday rides with athletes on the same system.

Next step

Put the science into practice

Test in the lab or train with a coach who uses your data.

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