Many sufferers just want their lives back. Probably the best way of doing this is by accepting the fact that you are having panic attacks and looking for ways of dealing with this and giving it less and less power over your life.
One question people ask is whether exercise is good for you. Exercise in moderation is always good for you but making sure that you are breathing well is even more important. From my personal experience of panic attacks, I have seen it with people who smoke heavily. A combination of this and a tendency to breathe quite shallowly means you're only taking in a fraction of the of air you need, and may contribute to the physical causes that bring on panic attacks.
So before you embark on an exercise spree, perhaps the most important thing you can do is relearn how to breathe using as much of your lungs as possible. You can find lots of information on the web and Youtube to help you with this. But owning up to your problem with other people can be very helpful. Which is why I would recommend coming along to the Breathing Break Club on Wed lunchtimes at 1pm. Sharing a problem gives it less power.