1. Hunching your back. This can cause slipped discs and some muscle issues.
2. Trying to controlled-lower the bar to the ground. Contrary to the policies of a lot of gyms, you should get to the top of your deadlift and basically drop: you might keep your hands on it to keep it from rolling away after it reaches the ground, but you definitely don't want to try to slow it down as you lower. If this is too loud for you, use bumper plates or a deadlift platform. This is pretty much guaranteed to cause you severe soreness and tightness as you go up in weight, which will likely clue you in that you are doing something wrong, but if you persist or jump right up to too high a weight, you can tear muscles or ligaments.
Both of these can cause pretty serious long-term injuries. But they're also both pretty easy to fix.
Agreed. I would also add that mobility issues are a short-cut to injury. You have to have great mobility in your hip flexors, IT bands, and ankles in order to perform deadlifts well (as well as any other lower body movement).
Sumo deadlifts are easy enough for a novice and are relatively lower impact. Form strictness is less of an issue for most people with these, and are a good starting point for deads.
Interesting, I looked it up, and apparently there is more disagreement on this than I was aware of.
If you read in depth on the subject, most people are saying it can fall pretty fast: controlling the bar seems to be mostly directed at making sure it takes a straight line down and doesn't hit your knees.
However, some people are saying that they lower it slower to get more work per rep.
All I will say is that my personal experience is that trying to over-control the lower has caused issues for me, and a few other people I've known who deadlifted, and these were always fixed by the cue, "Just keep your hands on it and otherwise let it drop."
And the flipside is definitely clear: if you watch any high-level deadlift competitions, tons of competitors will just completely let go of the bar, and I'm not aware of any injuries caused by doing this.
That said, I'd love to see actual data, as the only information I have found here (including my own) is just appeals to authority.
1. Hunching your back. This can cause slipped discs and some muscle issues.
2. Trying to controlled-lower the bar to the ground. Contrary to the policies of a lot of gyms, you should get to the top of your deadlift and basically drop: you might keep your hands on it to keep it from rolling away after it reaches the ground, but you definitely don't want to try to slow it down as you lower. If this is too loud for you, use bumper plates or a deadlift platform. This is pretty much guaranteed to cause you severe soreness and tightness as you go up in weight, which will likely clue you in that you are doing something wrong, but if you persist or jump right up to too high a weight, you can tear muscles or ligaments.
Both of these can cause pretty serious long-term injuries. But they're also both pretty easy to fix.