User blog comment:Lord Loss/Discussion of the Week: Swimming/@comment-78.114.73.228-20130127103103/@comment-5043481-20130127163206

There is a way to move vertically without changing the camera angle...

On the classic controller it is Zl/Zr, the big buttons on the top (NOT the ones that block/item select). Ones goes up, one goes down. Unaffected by camera angle.