Today on my way to a swimming lesson, i wondered why swimmingpools with other kinds of liquid mass in them havn't been invented? I was wondering if water with a different density and lighter mass wouldn't equal that a human beeing would more easily go through the water and not hit himself as bad if he trains jump-ins and such. Why havn't a lighter mass watertype been invented? Wouldn't it be perfect for huge jump training so you wont hit yourself as bad. A downside would ofcourse be (I believe its Newtons law) that you wont swim as fast because of friction (action/reaction) would be less. Any way, just a thought :) New to the forum. Hello all. Ps: Please bare with me. Im not a physics major or anything classy, just interested.