This is my 20th year in the sport. I've known swimming and that's it. I don't want to swim past age 30; if I continue after this Olympics, and come back in 2016, I'll be 31. I'm looking forward to being able to see the other side of the fence.

In his second event the 100-meter butterfly Phelps just edged out Ian Crocker 51. 62. 23.

He expects to do further work with his foundation after the 2012 Olympics which he has said will be his last. Five of those victories were in individual events tying the single Games record. In the 2012 Summer Olympics in London Phelps won four golds and two silver medals making him the most successful athlete of the Games for the third Olympics in a row.