[klue07]

I wouldn't entirely agree. If you aren't lifting any relatively heavy, extra weights, e.g. running or something, warming up isn't as important. However, when lifting relatively heavy weights, I think warming up is pretty important.

Warming up has the benefit of lubing up your joints. I think we've all had the instance where our body are relatively stiff and if we do, say, a push up, our joints pop or make cracking sounds. I remember squatting once when I didn't fully warm up. My knee wanted to pop during the squat and it felt extremely uncomfortable trying to exert force on that leg. When there isn't any extra weight, merely extending your leg with a pop wouldn't bother anybody, but exerting a lot of force and doing so slowly sure wasn't a pleasant experience. What are the chances of serious injury? I don't know, but it hurt enough for me to not want to find out.

Another thing warming up helps with is to acclimate you to your working set weight. I know the first set of my bench press usually ends in a grinder and is the roughest out of all my sets. I'm not sure if it's just my mind acclimating to the weight or a physiological thing like more blood getting pumped to my muscles. Either way, I'm fairly certain (but do not have any sources) injury rates would be increased if you tried to deadlift your max without properly warming up.

[epimetheus]

I think you missed that stated I do a few warmup sets for all of my main lifts and that I lift heavy (5 rep max, sometimes 3rm and 1rm depending on lift and day). However, I believe most people do too many warmup sets which limits their working set and slows progress and gains. Doing 3-4 working sets in reasonable increments is just fine. I know people that do 20 total sets per "body part", only 3-5 of them that are working sets (because that's what the bodybuilding magazine reported <today's Mr. Universe candidate) said they lift).

The running thing seems less likely to be true though. I wouldn't put my bed in a field, sleep 8 hours, hop out and go full out on a sprint, but I'm not going to do 20 minutes of stretching or ride a bike before doing a few sets of sprints.

Long distance warm ups seem even less likely to be needed than Sprints.

And, for what it's worth, I've done "max effort" deadlifts without warming up once or twice. Mostly to show off, but I had lifted those weights before (that day in one case, a couple days back in the other), and didn't have any issues. I could have been hurt, I guess, so my 'anecdata' is no evidence, but even so, not warming up isn't a guarantee of injury either.

[klue07]

I have a feeling that your true 1rm is higher than you think it is if you can pull it off without acclimating to that weight.

I never said you will for sure get injured, merely the chances increase. And I agree that some people have warm ups that are too intense.