The main issue with exercising and aneurysms is the probable sudden increase in BP that happens when performing certain exercises. Anything that makes you hold your breath and/or grunt when exerting can punctually raise your BP to really dangerous levels, especially at the size of your aneurysm. One of the things you can do is to find a PT Dr that can help you learn how to properly breathe when exercising. I would avoid heavy lifting and exercises like crunches since no matter how much you learn we sometimes unconsciously forget and hold our breath (at least it happens to me). But you want to stay active and keep your body healthy, there’s a balance (I believe the video gives some good advice and explains well the options)