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The definition of an Olympic size swimming pool is 10 lanes each 2.5 meters wide, however to prevent the outside lanes being disadvantaged by having to compete with the waves bouncing off the sides of the pool only the middle 8 lanes are ever used.
50 metres long with 8 lanes
An Olympic size pool is length 50 m (164 ft) by Width 25 m (82 ft). It has ten lanes.
Competitive swimming pools widely vary in width. The width (in feet) changes depending on how many lanes it has. Most competitive pools have either six, eight, or ten lanes. An official Olympic sized swimming pool is 50 meters by 25 meters. It is ten lanes wide.
8 lanes.
It depends in the standard of the simming race, for Olympic or World Championships then the pool has to have 10 lanes however only the middle 8 are used. For lesser competitions it depends on how many lanes the pool has, usually a minimum of 6 however for smaller and older pools which are very rarely used there may be 4 or 5 lanes
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It has 9 lanes. What's my prize?
FINA which is the world governing body for international swimming calls for a 50 Meter pool with 8 lanes. However movement is being created for having pools built with 10 lanes, with the outer 2 not being used for competition. (The waves created by swimmers bounces off the side walls and 'slows' down the swimmers in those lanes, thus an buffer is created by not using lanes 1 and 10 in competition). That said, if you are talking about size, Olympic generally refers to the length of the pool, not the number of lanes.
An Olympic-sized pool is 50 meters long, so divide that in half and you have 25 meters, a distance that is frequently used by countries other than the US Answer 25 meters. It's used all over the world. There are only 2 sizes for swimmin pool competitions: 25 and 50 meters. 50 meters is the so called olympic sized pool.
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