Originally Posted by javyn
Manton, you'd be surprised how using a bar rather than dumbbells completely changes things.
+1. I can't imagine doing anywhere close to my highest weight with dumbbells, nor with form anywhere approaching correct for a low back squat. Some upper body muscle will probably give out well before the muscles you're supposed to be training with the squat will from holding the dumbbells in place. With a barbell, it's basically gravity holding the weight in place.
I'd really try to find a barbell with an adjustable power or squat rack (the safety pins should be movable up and down, so if you can't stand up again, you can put the barbell down) to do squats properly.
Originally Posted by RedLantern
If your knees are over your ankles, and the weight is over your ankles how would you not fall over considering that the rest of your body would be behind your ankles?
Edit: I think you meant when initiating the movement, not throughout. my bad
You have to lean forward to balance yourself --- the barbell needs to be over the center of your foot. The knees should move out to the final positions (somewhere over the toes) by 1/3-1/2 of the way down, and maintain that position to the bottom and up again. There are two reasons for this:
1. You don't induce tendonitis in your groin area. Believe me, this is no fun at all.
2. You recruit the hamstrings more actively, so you train them more, and you can move more weight. If your knees slide forward at the bottom of the squat, you will release tension in the hamstrings, so they cannot be used to help you get up again, and they are not trained as intensely.
These two things are covered in SS in more detail.