During, or at the end of the arm pull-down of the first stroke after the start and after each turn, a single downward butterfly kick is allowed, but not required, followed by a breaststroke kick.
During, or at the end of the arm pull-down of the first stroke after the start and after each turn, a single downward butterfly kick is allowed, but not required, followed by a breaststroke kick.
出发后或每一次转身之后，在第一次大划手之当时或之后，一次向下蝶式踢腿是被允许的(但非必要的)，然后拌随一次蛙式踢腿。