I agree with Prince.The two major form points on the squat are stance and bar placement.Start with a shoulder width stance(make sure the toes are angled out slightly)and experiment with the way it feels.Most lifters who are tall might need to use a wider stance in order to reach the correct depth.Speaking of depth, you want to squat down until your thighs are atleast parallel to the ground.If you want to really bring the hamstrings and glutes into play, try to achieve a below parallel stance.Take caution here though as a low position is too stressful for some people's low back.As for bar placement, start with the bar placed on the traps.If that is uncomfortable, lower it so that it rests behind the deltoids on your upper back.Again, taller lifters usually find a low bar placement more comfortable.Another important point is bar control.If you grip the bar just outside the shoulders it forces your shoulder blades to pinch together.Holding this position tightly will allow you to keep a flat back during the lift.This is very important, because if your back rounds during the lift, you open yourself to injury.A close grip also lets you control the bar better.I have seen lifters who grip the bar almost out to the collars, and there is no control there.Also, try to tense your muscles and "stay tight" during each and every rep.This will reduce the chance of injury.A training partner of mine use to relax when he was in the low position of a squat and severely injured his low back.Try to keep your torso as upright as possible, that is, don't lean forward excessively.This puts tremendous stress on the low back and should be avoided at all costs.If you find yourself uncontrollably leaning forward, reduce the weight on the bar and try to hone your form.Also, excessive rounding usually indicates a weakness in the lumbar(low back) area.So focus on good moprnings,back extensions or romanian deadlifts to help correct the problem.Experiment with these different techniques and find what is best for you.Squatting in front of a mirror initially will help you find flaws in your technique.Or, have someone you trust to watch you squat and give you some feedback.That is about the best description I can give you.Sorry, no pics.
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matt toupalik