See Dick Run, Bike and Swim

Triathlons for children have become tremendously popular, drawing participants as young as 3 (who probably did not come up with the idea themselves).

Some races let children as young as 3 participate, using swim floats, bodybuilding, training wheels or even tricycles. “If you want to start a child when they are really young, understand they aren’t doing a whole lot,” said Ms. Osgood, who said that she considered age 8 or 10 a reasonable age to start.

A triathlon “combines three things kids like to do: swim, ride their bikes and run around,”

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