I took swimming classes for several years and I don't think I needed anything to be different for me because of my aspergers. I had fun, learned to swim, and still love to swim. I had trouble with diving and only ever dived headfirst from the diving board once, and I never mastered the butterfly stroke, but that's all. The first is out of fear (irrational fear, so I have no explanation as to why I don't like diving), and the second is just that I never got the skill. I'm not particularly athletic and the butterfly stroke is difficult.