chair sits are where you place your back against the wall, with your feet out in front of you, your knees bent almost 90 degrees. imagine sitting on a bench up against the wall and having the bench removed--you look like like you're sitting but are actually doing a squat. you just hold that position for a little while, maybe while you brush your teeth or listen to a song. eventually, your knees will start to shake laterally, and that's how you know you're giving a workout to the stabilizing muscles.

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