When I swim the crawl (freestyle) I breathe on my right side. I have tried to breathe on my left side but can not seem to be able to turn far enough. I have seen some swimmers who breathe left and right side and do it very smoothly in a 1 2 3 4 breathe stroke rhythm. I useually breathe on the right side with a 1 2 stroke rhythm and sometimes on 1 2 3 4. I wonder if the proper way is to use the left right breathing rhythm and how do the fastest swimmers breathe all on one side or both? True I swim for exercise but it is still fun to learn new things to better my stroke.