Swimming competition in which any of the standard strokes may be used
The referee can disqualify (or DQ) any swimmer for any violation of the rules that
... [DOC] [TLE] Medley swimming - Wikipedia [PAR] Medley is a combination of four different swimming styles breaststroke, 
backstroke, butterfly ... Swimmers may do this by pulling the knees underneath of 
their body after ... For medley events, freestyle means any style other than 
backstroke, ... that none of backstroke, breaststroke, or butterfly stroke may be 
used for this leg.