Olympic-sized pool
Olympic-sized pools were those used in the Olympic Games, and thus were places where one could attempt to break Olympic records. Miranda, for instance, was a swimmer who tried to break the Olympic record, even though her friends, like Dinah, were merely attempting to be competitive at the county level. (PROSE: Father Time)
Of course, not everyone who used an Olympic-sized pool was trying to break any records whatsoever. On at least one occasion, Ace swam in the TARDIS' Olympic pool, noting to herself that it had "all the trappings of a council house bathroom", and that the Doctor called it a "bathroom". (PROSE: Loving the Alien) Since it had wicker furniture with fluffy towels on it, white plastic loungers, and many plants, it shared at least some commonality with the pool Leela once encountered in the TARDIS. (TV: The Invasion of Time)