If playing sports wear out the body over time, why does it keep you healthy at the moment?

Question

Notice how everyone always tells you to exercise, workout and play sports because its good for the body. How about as you get older people always say well, you had wear and tear on your body over the years. They say long term it's bad for you. Well, I can understand Football, and Boxing because they are hard contact sports and the body is not meant to take that type of beating. Basketball, players get back injuries and bad knees from all the jumping, and excessive running. Is there supposed to be a time to stop playing all sports at a very early age. Players like Kareem Abdul Jabbar, Robert Parrish, Dave Winfield, Jerry Rice, Michael Jordan, Karl Malone, Nolan Ryan. Old school older guys who played for a very long time in their sports. It's partly genetics, but of these people do you see them old and crippled years from now? Because they're bodies are in good condition and they've been playing for years. It goes against the grain on that answer about wear and tear, these guys aren't.

Answer 1

Football is for men made out of rubber.

And with all sports, when you are you of course you play better.

But I played a tennis match against a 72 year old dude, he almost killed himself, but he won.