There are a lot of ab exercises that you can do in the water. There's a lot that I like to do in deep water. It gives you a little bit more of a workout. You can use the noodle float or you can use a belt, you won't need a noodle. So whichever one you have would work.
The first one we are going to do is called a frog kick. You're going to put the noodle behind you and you're going to float normally in the pool and we're going to kick our legs out, pull them in, kick them out, pull them in. This is called frog kick. You're going to do that about 15 times, and then you can reverse the direction, so you can kick out first and then come in. Kick out and then come in.
You can also do regular bicycle, and you can do scissor kicks as well. Your feet are going to have a tendency to drift towards the bottom. You're going to have to pick them back up and do it again.
Another great thing you can do for the ab workout is something I call rowboat. What you do is you sit on the noodle and you put your legs up. You want to sit towards the back, put your legs up, and row the boat. This is a little hard, because you're going to have to balance. The further back you lean the better.
What you want to do is come forward, and I usually do this the whole length of the pool, so I come all the way down forward and once I reach the end, I'd back up. It's really good for your whole core, not just your abs, but your back, and it's a really good workout for your arms. So there are some exercises that you can do for your abs. They are really great, and the deep water is definitely the place to do them.