I just turned 49. I've been doing CrossFit for over 8 years in two different gyms and about a year in my garage. I've been in nearly fifty CrossFit gyms when I travelled for work. They are all different. I'm not the fittest guy. I'm a busy dad. I've had one injury during that time. That came from playing basketball at Iowa State Basketball camp when I ruptured my Achilles tendon. If you can't control yourself you can get hurt doing CrossFit just like I did playing basketball. You warm up. You tone down your ego for the first month or so. You use weights you can control. You don't go too fast ever. You get faster as you become more attuned to the movements. You ask questions. You get used to not being the fastest. Occasionally your kid asks you why so many people finish before you. If you jump in and max hard the first week you won't be able to go back even if you didn't hurt yourself because you won't be able to walk. In my experience, the better gyms and the ones with the least likelihood of injury have very organized classes with coaches who actually instruct (not just say "ok were starting in 5 minutes), where they warm up as a group and also demonstrate the movements before the workout, and where they warm up with the movements in the workout that day. But some people love a CrossFit gym where it's much less structured. If the first day you walk in they hand you a barbell and turn you loose, put the barbell down and leave. Find a different gym. If you've never Olympic lifted before that's how you get hurt. I did Farrells and Kosama before that, and liked both of them. I ran marathons and road races before that. CrossFit isn't better or worse than a lot of other programs. It is simply different. It has a different philosophy. Like someone said if you've been taught to make the movements strict then lots of people have a hard time with CrossFit's willingness to use momentum. If you like to grind out 45 minutes every time you work out you'll struggle with a day where it's 15 minutes of max squatting, or a 7 minute sprint style workout. The only way to know if you like it is to go into a gym and try it. If you like what you see at that gym. Give it a month. It might not be for you. It might be. If you kind of like it but the gym doesn't fit you try another one nearby.