Who are the greatest Olympic swimmers in history?
This habit doesn't exist strictly among olympic swimmers; many competitive swimmers splash or feel the water before a race. Some may use the water to adjust goggles or caps, others prefer to wet themselves in order to prepare for the temperature difference (competition pools must be between 25-28 °C (77-82 °F)).
for swimming there is a meet called Olympic trials to reach that point there are tie standards you must reach. From that point the swimmers swim once in prelims where the top 16 move on to semi finals once the swimmers swim here the Field narrows even more down to 8 swimmers finally the swimmers swim one last race in the finals the top two swimmers in that race go to the Olympics