I'm frustrated. I hired a trainer last fall when I started doing BB squats because I wanted to be sure of my form. He told me that putting my heels on plates would help if I had trouble. They did help, or so I thought. Then I read in the March M&F that this is NOT good form and that using a board shifts the resistance and doesn't hit the muscles correctly and can also cause knee injuries. I stopped using plates and now my form is off (I tip forward) so I need some advise on what to do.
I've never done squats with anything under my heels. The way I try to keep my form is to think about keeping all my weight on my heels -- even to the extent of almost lifting my toes off the ground -- and starting the downward movement by sticking my butt out FIRST, then going down. I think as women we feel a little self-conscious about sticking our butts out at everyone in the gym (I face a mirrored wall when I do these) but the further I stick it out, the better my form is. Some people say pretend that you are sitting down in a chair.
I've NEVER done the plate-under-the-heel thing - I just try and DRIVE my heels into the floor as much as possible, just like when I do crunches I push my belly button as close to my spine as I can (or at least try to!).
I always squat flat-footed. In the beginning I experienced the same problem with keeping my balance. I found that by picking a spot on a wall directly in front of me to focus on enabled me to keep my balance. You keep your eyes on the same spot as the movement is performed. What this does is help you to keep your head up and your back straight.
If you use plates under your heels, you are isolating the quad muscles (especially the lower quad area) and not using your hams and glutes as much. If I'm working a "quads" only day, I squat with a much lighter plate load with the weight on the balls of my feet (as if I had plates under my heels.) This is a quad KILLER! I also wrap my knees quite tightly, because it is harder on the ole knees.
For a complete lower body workout, you need to get your weight back onto your heels as Meg described. If your problem is balance, try focussing straight in front of you, head up, butt out. If your problem is very tight achilles tendons, do a couple of other exercises first to warm up, then some progressive tendon stretching, then try squatting.
Another option is "sit squats". You'll need to lighten up because You'll have NO momentum working for you. I don't know if its possible to do these with dumbells, tho. place a platform right behind your legs, and starting from regular squatting position, sit down. Now stand up with your weight on your heels. It's a lot harder than it sounds. The first time I tried it, I used the same amount of weight I usually squat, and there I sat. No way could I stand up. (very embarrassing!)
Stick that butt out girl! And widen your stance a bit more too. That should help you sink down and come back up from your heels. Turn your feet out just slightly as well, this will help you keep your balance.
Practice 'hover' squats using a chair at home or just get in and out of chair using just your legs and butt to propel you up and take note of how you do it. I'd practice squats w/no weight until you have the form down perfectly.
Here's a little pro help:
Squats
This is the most popular exercise to develop the upper leg. It works the thighs, the hamstrings and the glutes. The drawback to the squat is that the main development occurs in the early part of the rise and that it never truly works the highly important vastus medialis muscle
How to do:
1. Get in a comfortable upright stance with your feet shoulder width
apart. Your toes should be either pointed straight ahead or slightly
outward, never inward or knee strain will result).
2. Focus your vision straight ahead. Do not tilt your head backwards or
raise your eyes in your head as this will disrupt your balance.
3. Place the barbell squarely on your traps and shoulders (not the neck)
and grip the bar comfortably with your hands slightly wider than your
shoulders.
4. Keeping your heels planted firmly on the floor, inhale and move
your butt back and downward. Do not start by bending the knees.
5. Continue downward, by bending the knees, but be careful not to allow
your knees to move forward. This will save you stress on your knees.
6. When the thighs reach parallel, begin exhaling and return to the starting
position. There should be no sideways movement, especially in the knee
or hip area.
7. Squatting deeper than parallel to the floor will not damage your knees
as many lifters believe. Knee damage is a result of raising your heels off
the floor, not by lowering your butt to the floor. Be aware, however, the
deeper you squat the more you call your hamstrings into play.
Thanks for all the great advise everyone! I'm printing it all out, as well as the info in the links you provided. I think I am going to have to do some weightless squats at home to work on my form in addittion to the BB ones I do at the gym. An other reason I'm frustrated is that the weight I use is still so low. I've got very strong quads so I should be able to do a lot more than I am.
Mindi, my Firm video actually has you do "hover" squats! I just seem to do them completely differntl with a BB. How wide should I place my feet?
do them as wide as is comfortable Deb. And turn your toes out slightly too if that's comfy as well.
I actually do my squats w/no shoes on. Of course I do them at home so I can away away with this, but I find I can dig in a bit more, heelwise, w/no shoes on. I wouldn't recommend it at a gym tho..hygiene and all.
Those freakin' hover squats! Cathe Freidrich does those w/a barbell, its enough to take you all the way down to serious failure..but we love it, right? *S*
Squats
I stopped using plates and now my form is off (I tip forward) so I need some advise on what to do. 
