Recently swimming has instituted a new rule on kicking off of the wall, commonly referred to as the Lochte rule. Backstroker, Ryan Lochte may be said to have the strong underwater kicks in the sport. Recently he started kicking off of every turn on his back in freestyle events. For him this was faster. Swimming’s governing body stepped in and created a rule that this qualified as backstroke (since you are on your back). This new rule has created one point of confusion for many swimmers. It is only illegal to do this in individual medley (IM) events. It remains legal to do this in freestyle events.
Why the difference? To answer that you need only listen to how an IM event is announced by a starter. A 200 (Short course) IM is announced as two lengths of butterfly, backstroke, breaststroke, and anything except the first three. Since backstroke is one of the first three strokes you cannot repeat backstroke during the fourth leg. Swimmers who are pushing off on their back in freestyle events cannot allow this habit to translate into their freestyle during the fourth leg of an IM.
There you have it, hope this clears up the confusion around the new underwater kicking rule. Don’t be surprised if it continues to morph over the next few months. New rule interpretation often takes time to settle to a consistent application.