Maybe, although video analysis from across the Internet is not a real substitute for having a coach. There may be something else that needs to be addressed. Also, your knees going back is a pretty subtle thing. I have seen much worse.
If you pay attention to them, you can usually feel your knees go back. Think of keeping them in place an moving straight up. It's not easy to do as things get heavy.Are there any physical cues I can follow to ensure I'm driving up and not back?
You can always check the Starting Strength Coaches directory, but I think there's only one dude in NC right now and he's not terribly close to UNC:And I'm at UNC, where I'm sure there are some coaches, but none for regular students. Shame I'm not on the football team.
http://startingstrength.com/index.ph...5b0d4dbc9985b/
If we really wanted to be picky, I would also say let your knees come more forward early in the squat. However, it's tough to say for sure from the video.Break at the knees and hip and drive UP not back. I'm glad we've finally found SOMETHING wrong with my form, because it never felt quite right.
There is no way to absolutely ensure that your back will be safe during a deadlift. You are correct that keeping lumbar extension is key. I really like Rip's "squeeze the chest up" cue. However, picking up heavy weights does carry a risk of injury. If you hold your back in extension, use the Valsalva maneuver, and keep things tight, you minimize that risk.Oh, and one more question while you're around, Tom, what can I do to absolutely ensure my lower back is tight and safe in the deadlift? Should I really focus on arching my lower back before I pull?