Open water swimming takes place in natural bodies of water rather than pools. It introduces challenges absent from pool swimming: navigation (sighting), currents, waves, cold water and variable visibility. Triathlon swim legs are almost always open water. FINA/World Aquatics sanctions marathon open water events at 10km (Olympic) and 25km (world championship). Most open water swimmers add 8-15% to their pool pace to estimate open water times. Safety practices include never swimming alone, using a tow float and knowing conditions.
Key points
- Natural water: lakes, rivers, oceans
- Navigation (sighting) is a key skill
- 8-15% slower than pool pace for most swimmers
- Always swim with a partner or group; use a tow float