Swim styles
In competitive swimming, four major styles have been established. These have been relatively stable over the last 30 to 40 years with minor improvements. They are:
Butterfly
Backstroke
Breaststroke
Freestyle
In competition, only one of these styles may be used except in the case of the individual medley, or IM, which consists of all four. In this latter event, swimmers swim equal distances of butterfly, then backstroke, breaststroke, and finally, freestyle.[13] In Olympic competition, this event is swum in two distances: 200 and 400 meters. Some short course competitions also include the 100-yard or 100-meter IM – particularly, for younger or newer swimmers (typically under 14 years) involved in club swimming, or masters swimming (over 18).
