Do a test run in your bathtub.. You'll see. It won't be very comfortable. It will get heavy and waterlogged.
What happens when you swim with a pad? I'm not allowed to wear tampons and I have to go swimming because I'm a camp counselor. I'd wear a tight bikini so it won't float away and board shorts over.
You would end up soaking up all the water leaving the pool dry. Pretty much ruin everyone's summer vacation. You should use a Maxipad with caution, those things are extremely powerful.