I am wondering if you can still be a competitve swimmer with T1 diabetes? What about a gymnast?

Of course! Have you ever heard of Gary Hall Jr.? He's competed in the olympics before.

The quarterback for the Denver Broncos is a diabetic, Jay Cutler. Exercise is good for controlling your diabetes. Talk to your doctor about regulating your blood sugar during intense exercise. He or she will likely tell you to eat something before you exercise and to check your blood levels afterward.