How to Teach the Butterfly Kick

Tell Swimmers to 'Pretend They Are a Dolphin'

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The butterfly is one of the most difficult swimming strokes. Timing the kicks with the proper leg motion is hard for swimmers to master. But the kick is vital to the stroke and also can be used underwater in a start or a turn. Therefore, a precise method for teaching the butterfly kick is a valuable skill for any coach.

When teaching a swimmer who has never done the butterfly, or dolphin, kick, I have found most of the competitive butterfly kick drills only make learning the butterfly kick more difficult.

In some cases, they even promote bad habits. For example, while the kickboard is a fabulous tool for learning just about any kick -- freestyle, breaststroke, even scissors kick --  I don't want one anywhere near my young butterfly swimmers.

Why? Because it promotes a premature knee bend. While a child is attempting to keep the legs together, the fly kick with a kickboard makes it nearly impossible for a beginner to get the core involved. An elite swimmer, whose kick has become automatic, can handle it, and it can be useful to work on tightening the abdominal muscles. But it encourages a young swimmer to draw the knees forward, which is a major setback and promotes extreme frontal drag.

Other butterfly kicking drills, such as the side body dolphin, vertical dolphin, and back body dolphin, are great ways to practice kicking, but I save them for swimmers who can already do the stroke legally.

They are too complex for swimmers just learning how to do the kick.

With beginners, I primarily emphasize a drill we call the body dolphin butterfly kick. The drill is done in a prone position, and you teach swimmers to make the butterfly kick incorporate the entire body, not just the legs. We use learning cues such as "Kick the head down," "Kick the head up," "bottom down," and "bottom up" because they help young learners get the hang of getting the core involved vs. just kicking from the knees down.

I also like to encourage my young learners to kick with their legs together, like one big flipper, and even to pretend they are a dolphin or a mermaid.

While I don't like to get too detailed when teaching beginning butterfly swimmers, it's important for teachers to understand the action of a good butterfly kick. In a nutshell, the legs are fairly straight during the upward action of the kick, and then flex just before the downward action. The legs continue to accelerate kicking downward until they are hyperextended.

Finally, in a swim lesson teaching the body dolphin butterfly kick, discourage your students from ducking their heads. While you want them to kick the head downward to promote the necessary undulation, a kick that's too deep will slow forward progress and increase frontal drag.