Thanks for all of the advice everyone! It was good to hear all of your stories about how you are still able to stay active and do the things you enjoy. I am going to continue to run and lift weights like I have always done, as I always am very controlled with my movements and not violently jerking around or anything.
I feel like doctors sometimes forget that most of their patients follow their advice to a T, so if they are merely giving a personal opinion that has not been validated by research, they should say that. Otherwise, people may end up changing their whole lifestyle, possibly for the worse.
I have never heard about someone ripping out their staples from exercising. I'm sure it's possible, but it seems like it would have to be from an accident while lifting heavy, similar to the way people get hernias. It certainly doesn't seem like a common occurrence that happens by lifting more than 25 pounds.