I don't follow golf, but have heard the narrative that Tiger 'ruined' himself with strange workout and lifestyle decisions (not talking about all the women). Is this actually the case? I always assumed it was exaggerated, but don't actually know anything about it. Back injuries are just a bitch and I assumed some people decided they needed something to blame.
LONG POST WARNING
Depends who you believe. He got into heavy lifting and SEAL type training apparently broke him some more.
I don't buy into it all. It's more the swing changes IMO. Tiger's always wanted a swing of his own. After the first Masters he won way back he went into a bit of a funk for about 2 years (as in results weren't what people expected) because he decided to do a complete overhaul of his swing which some considered (and still do consider) to be nuts especially for a guy that was young and already winning. This was probably before his whole "I want a swing people remember me by" thing but I feel it was more his thinking that he could see where golf was heading and wanted to get ahead of the curve. The early 2000s happened then he decided to change (I think as well to get distance).
On the injuries front, because of all the training he was doing and certain "moves" in his swing was putting stress on parts of his body. I could be getting my timelines wrong (ie it could've been after the US Open, pre Sean Foley who I'll get into later) but he adopted a move where you effectively snap your leg straight at impact as another moving cog to create more lag at impact to get more distance. That "snap" puts a lot of pressure on the knee and I believe (again if I have my timeline correct) was a contributing factor in the US Open he won on a "broken leg". I vaguely remember Rory McIlroy doing the same thing and straining his knee a few years ago that was attributed to the same move.
When he came back again following the Thanksgiving attack with a (I believe) 7 iron, he again made changes to his team including taking on Sean Foley as his instructor. He made changes to his swung, including a more forward leaning shaft at impact and a steeper angle of attack. Tiger also became obsessed with numbers (Trackman etc) as this was Foley's style of teaching where it didn't matter how your body got you there, all that mattered was the numbers. I think at the end of the era, he was just doing all these things that put more pressure on his back and blew it out, again, proper. In fairness, he had good success early on (I think it was 2010 where he won 5 tournaments, including the WGC and possibly even the FedEx) but I feel that chasing the numbers just put his body in a position it shouldn't be in.
^^ That is all off memory, so forgive me if some of the stuff is wrong. I did a lot of reading on it as it was about the time I became a bit of a golf addict and tragic.
Now for my opinion. Where he probably overdid was he didn't give himself enough rest. I was reading stuff like he was doing the sleep deprivation stuff. That, without being there, we'll never really know and I don't trawl enough the S&C forum to even pretend like I know what I'm talking about whether it was "good". I don't think the weight lifting hurt as much as people say. He didn't get completely yoked... he was yoked by golf standards which ain't a especially high bar back then or now. I think the only thing it might've hurt is his flexibility, but he was going to lose some of that with age anyways. Brandel Chamblee is going to harp against it (when Tiger was on the shelf, he changed target to Rory). I don't think it hurt Rory's game much either.
Look at the other guys considered big these days in Brooks Koepka and Dustin Johnson. Doesn't seem to hurt them but I think those guys are naturally huge and have been lifting since their teens.
Feel free to dismiss anything I've put up there guys. Fire suit is on