In the movies, Tarzan always uses the front crawl stroke (what we often call the freestyle). And with good reason. The front crawl (aka the forward, American or Australian crawl) is the fastest and most efficient of all the swim strokes. Swimming is such an essential Tarzan skill that the movie producers back in the 1930s brought in Johnny Weissmuller, a five-time Olympic gold medalist in swimming, to play the role of Tarzan.
The technique for the Tarzan front crawl is pretty basic. Float face down in the water with both arms stretched out in front of you. This is the starting position. Flutter your legs alternately in short, up and down thrashes. The arms move in alternating sweeping strokes. The arm movement can be broken down into three parts: pull, push, and recovery.
There's even a bonus section on how to emulate Tarzan's (or, specifically, Johnny Weismuller's) distinctive yell. Link -via Gorilla Mask