Event programsSwimming

1.5 km Open-Water Swim: 8 weeks, peaks at ~4 h.

1,500 m in open water — essentially a threshold event: CSS is roughly 1500 m time-trial pace, plus sighting, starts and drafting. That's the intermediate plan; beginner runs 10, advanced runs 6 weeks.

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Written for where you are.

Beginner

10 weeks, 3 swims a week: from 600 m continuous to a 1.8 km dress rehearsal, first open water in week 5.Shortest runway 7 weeks · research minimum 8 · 4 sources

10 wk

1-2.5 h a week

Intermediate

8 weeks, 4 swims a week: CSS from 15×100 to 3×600, the long open-water swim to 3 km with a negative split.Shortest runway 5 weeks · research minimum 6 · 4 sources

8 wk

2.5-4 h a week

Advanced

6 weeks, 5 swims a week: one CSS key and one VO2 / USRPT or start-surge key, open-water volume to ~4 km.Shortest runway 4 weeks · research minimum 4 · 3 sources

6 wk

3.5-5.5 h a week

The checklist comes with it.

T-28Men over 40, or anyone with heart risk factors: get a pre-participation check. Two-thirds of US triathlon race deaths happened in the swim, mostly men over 40, often with hidden heart disease (Harris 2017).

T-7Water temperature and the wetsuit rule: World Aquatics races need ≥ 16 °C and make wetsuits compulsory below 18 °C. Cold shock is ~1 min of gasping, then swim failure within ~10 min — enter slowly and control your breathing.

T-7Goggles: one clear and one tinted pair, plus a spare. Anti-chafe.

T-3Course map: sighting landmarks and buoy colours. Start format (seeded, rolling or mass) — self-seed honestly. Know the exit and the safety craft.

race morningWarm-up swim of 10 min with 4×1 min at race pace, then a seeded or rolling start.

race morningCough, frothy or bloody sputum, or breathlessness in the water (SIPE): stop, signal the safety craft, exit and get medical care. Never swim open water alone.

Every plan cites its homework.

Finish-time bands are dossier estimates (CSS × 1.5 plus open-water drag), not race statistics. The 16 °C cold-tolerance limit comes from 20 trained swimmers in a flume; recreational swimmers may tolerate less. SIPE affects under 1.5% of triathletes — more often women, over-50s, people with hypertension or on fish oil, and in cold water, wetsuits and long swims.

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