usually I'll go down to where my legs create a 90 degree angle. It seems
on Crossfit that people suggest squating until your bottom touches your
ankles. Is this a better way of doing squats?
If you simply rely on your knees to bend at a 90 degree angle to determine depth, then you might be short changing yourself of the benefits of squatting lower. You can achieve a 90 degree bend in your knee and still be well above parallel (i.e. quarter squats).
"Go as low as you can while maintaining a low back arch when using weights"
Strong advice.
The basic way of teaching squat depth from the book I just bought, Starting Strength. Put your heels at about shoulder width, point your toes out at 30 degrees then squat down with your knees over your toes keeping your back straight. Place your elbows on the inside of your knees then place your hands together and arms straight-in, pushing your knees out for a stretch. This is the bottom position of the squat.
(Edit: I didn't really mention how low to far...look at this link http://www.exrx.net/WeightExercises/Quadriceps/BBFullSquat.html)
The author goes into detail about how doing partial squats can cause knee/back problems, especially if you are using more weight than you would be able to squat to full depth.
Here's some Olympic Lifting instruction videos but it doesn't go into a lot of detail: http://www.aceathlete.com/hatch/video.htm
Thighs parallel to the ground, if you can maintain good mechanics.
"Go as low as you can while maintaining a low back arch when using weights"
I agree with this, and I train my squats the same way. Keeping my back straight was something I got from a westside article I read. I think the trainee was told to squat with a broomstick until he achieved perfect form (straight back, etc.).
I basically do everything to get as low as I can, without my knees going past my toes, and keeping my back as straight as possible.
I have a tendency to fall backward if I don't engage my core. Squats are extremely beneficial because of this, because it trains the glute area, legs, and the core in one synergistic movement.
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This coordination of this rather complex area of the body (through squats) has crossed over very well into my ground game (takedowns in particular).
Personally, I wouldn't worry about how much weight I'm squatting. Focusing on the form alone has benefitted me greatly.
"I think the trainee was told to squat with a broomstick until he achieved perfect form (straight back, etc.)"
This is awesome advice. Too many novice lifters want to max out before learning proper form.
todd:
I forgot where I read the article. It may be on their site.
It's actually quite difficult at first, and requires some time and concentrated effort. Great for form, brutal on the ego. Don't try in front of the wife or gf. :)
Thanks for all the great advice. I am going to take it slow, and work on
my form. But one more question. Some of you have suggested keeping
a arch in my lower back while others have said keep your back straight.
So which one is the correct posture?
That would depend on your body and the amount of weight you are lifting. The main thing in squatting (with weights) is to keep the load over the heels. Some can achieve this with a straight back while others need to arch their lower back to ensure the load doesn't drift forward (which will turn your squat to something like a good morning - squat).
If you are doing squats with just your body weight, then there is hardly any need to arch your lower back; however, if you are training for your max, then arching your lower back is one of the things that will ensure a tight core necessary for completing the lift (whether you lift raw or with the gears).