Swimmer Ilya Kharun, one of Canada’s most promising athletes in the pool, has decided to compete for the United States.

Although the 100 butterfly is not one of her events on the international stage, Regan Smith has flourished in the discipline.

Swimming is one of the marquee Olympic sports, and it comes with a long list of rules. Between individual events, relays and medleys, there are a bevy of swimming races. Add in varying distances and ...