Hi
My old database calc, says
Aqua-aerobics, 15 mins = 1.5 points
Aerobics, 15 mins = 1.5 points
Swimming, 15 mins = 2.0 points
May be a bit out of date now, as have had it for a few years. Will give you a rough idea though, until someone comes along with a more up to date figure. :)...