In order to do a chest press or a fly on a BOSU ball, you want to lie on your back, keep the weights with you as you roll back, keep them on your stomach. And then you're going to look at the ceiling, and you want to keep your neck in line with your back. Go ahead and bring the weights out to the side. And then you're going to lift them right above your chest and then back down. Right above your chest. You can either bring them together or not. It's up to you. It doesn't make much of a difference. And down. And that would be the press.
In order to do a fly, you want to keep your weights together, palms in. And then you're going to open, keeping a little bend in your elbow, and bring them back together. So you don't want to go all the way down to the floor right here. you want to just go parallel to your chest, and then bring them back together. Open and together.
Now, there's a modification for this if you have neck issues, because it could potentially hurt your neck if you're not strong enough. And the modification for that is to just sit a little further down and rest your neck on the ball, keeping your hips up. And then you can do the fly and the press.