Imaginary chair

The imaginary chair or wall sit is a means of exercise or punishment, where one positions themselves against a wall as if seated. A wall sit specifically refers to an exercise done to strengthen the quadriceps muscles. The exercise is characterized by the two right angles formed by the body, one at the hips and one at the knees. The person wall-sitting places their back against a wall with their feet shoulder-width apart and a little ways out from the wall. Then, keeping their back against the wall, they lower their hips until their knees form right angles. This is a very intense workout for the quadriceps muscles, and it can be very painful to hold this position for extended periods. Wall sits are used as a primary strengthening exercise in many sports requiring strong quadriceps including fencing, ice hockey, sailing (mostly small boat racing), skiing and track and field.

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