This is common knowledge. Both retired pro soccer and handball players in my scandinavian countries almost all have a myriad of issues, most commonly and serious knee issues that require many operations.
I know several pro swimmers though and haven't heard of any serious issues there, so i guess it's from the impacts and constant running.
Heck, I'm Brazilian and it feels like 50% of males I know developed knee problem in their late 30s/early 40s
Almost all of them were weekend football (court, not grass) players. The others were week day players as well
Me, like the good nerd, I am developed back problems instead
I worked with a guy who played college football and had aspirations for the NFL, he was a wreck and always complaining about the lingering effects of injuries from his days playing. I guess this is somewhat expected with a contact sport, but I've also seen guys I knew who did a lot of high intensity training and after about 10 years or so seem to start aging more quickly compared to their non-athletic siblings.
I mean getting exercise is definitely good for you and in a choice between too much and too little I think you're better off overdoing it, but just constantly burning your metabolism at full steam seems to age you faster, couple that with the impact caloric deficit is supposed to have on aging and at least in my mind there's a pretty clear connection between the two.
As someone who did competitive weightlifting early in my life I don't think it's true.
First of all, a healthy body is very good at adaptation, i.e. if properly trained, your bones, muscles and other tissues get thicker and less prone to tearing, breakage etc.
Second, you will be surprised at how much pressure could daily activities put on your tissues, e.g. your vertabrae disks get higher pressure when you are wobbly sitting than standing even with some additional load. And in my experience people who train their body for extreme conditions have less problems in their elderly than people who never trained much at all.
And as you've noticed, most sportspeople have troubles with their serious traumas, not due to routine trainings. Plus of course this traumatization level varies from sport to sport.
In this friends case it was the NFL part that caused the damage. Not the fitness part.
I once did a boxing class. The day we did drills with with those boxing pads that require 2 hands to hold up, my head was throbbing for the rest of the day. Tried it again and same thing. Then I quit. Clearly I cannot take a serious punch.
Well, they tend to be bigger than other fit people (NFL players excepted), and they do a lot of jumping, which if all goes well is followed by landing.
