Dianne: The joint pain you are feeling in your knees is probably due to the form you are using when you are lunging and squatting.
First of all, lunging, at least I think so, is one of the more difficult things to do correctly. I had to build a lot of strength and single leg stability before I could lunge under control. When you are lunging, strike the front foot with the heel.Also, do not let the knee ride over the toes. Sometimes, people find lunging backward a little easier to do than a forward or walking lunge.
Squatting. Same things to keep in mind: Weight is in the heel of the foot and not the ball or toes and the knee should not ride out over the toes.
Another thing to note about squatting. A lot of people are more quad dominant when they squat which puts a lot of sheer stress on the knee. When squatting (do with with your own bodyweight first before ever adding weight) think about the movement originating in the hips. That is, you are going to bend at the hip creases and sit your glutes waaaay back. Focusing upon sitting the glutes/hips back will help prevent the knees from riding over the toes.
Joint pain is no fun. Might also be helpful to have someone evaluate your squat just to be sure everything is moving in the right direction.
These videos may be helpful too:
http://www.youtube.com/watch?v=kawBY5p29fQ
http://www.youtube.com/watch?v=-OoVQ...eature=channel
This one is really cheesy but I like the concept of using the ball out front as a proprioceptive cue for your backside to do the same in the back...She could be using her glutes to rise up out of the bottom a little more IMO. but other than that, it's another tool for your box while learning.
Best of luck!
