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Open-water swimming

How

Sighting, acclimatisation and the usual path from pool miles to a marked 2 km.

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Quick answers

Which local rescue or training agency should I check first?

Use the local lens: coastguard/federation norms and the shop briefing for that bay — not a blog visibility claim.

When did the Olympics add marathon swimming?

The 10 km open-water event debuted at the 2008 Beijing Games, held at the Shunyi rowing-canoeing park.

Who first swam the English Channel?

Matthew Webb swam Dover to Calais in 1875. The Channel remains the most famous ratifying-body swim, under rules later formalised by the CSA and CLSA.

Are wetsuits allowed in races?

World Aquatics and World Triathlon set temperature bands. Below a threshold wetsuits may be required or permitted; above it they are often banned. Always read the event’s rule sheet.

What is sighting?

Lifting the eyes to pick a landmark or buoy without breaking the stroke. It is the skill that replaces the black line.

Is a pool 1,500 m enough preparation?

It is necessary and not sufficient. Currents, chop, cold and navigation only appear outdoors.

Start with this section - How

The transferable pool skills are stroke and aerobic base. The new skills are navigation, temperature and exiting a beach or pontoon without a wall.

Organised events mark a course with buoys and cover it with kayaks. Informal swims need a chosen exit, a watcher on land or a tow float, and a decision to stay out if the wind turns.

Steps

  1. Build pool endurance first

    Continuous 1,500–3,000 m with bilateral breathing is the usual indoor prerequisite.

    Panic in chop is harder to fix than a slow 100 m split.

  2. Practise sighting in a pool

    Lift the eyes every 6–8 strokes on a painted target. It feels ugly and is the whole outdoor sport.

    A front snorkel can isolate the catch, then come off for sighting sets.

  3. Acclimatise gradually

    Short, repeated exposures teach the cold-shock gasp to settle. Do not jump a 10 °C gap in one weekend.

    A thermometer and a time limit beat bravado.

  4. First outdoor session with cover

    A club, a kayak, or a lifeguarded beach. Solo first outings are how competent pool swimmers make the incident statistics.

    A bright cap and a tow float are visibility, not a buoyancy miracle.

  5. Learn a two-exit plan

    Start and finish points that still work if the wind shifts. Rivers need an even stricter downstream plan.

    If the landing is a ladder, practise it in a calm harbour first.

  6. Race only on a marked course

    Buoys, a briefing and cut-off times exist because packs and feeding are chaotic.

    Read the event’s wetsuit and temperature sheet the night before.

Skills

Progression

Common mistakes

Open-water technique is sighting plus an exit plan. Distance in a pool is homework, not the event.

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