Start by selecting a sturdy piece of furniture, and a smooth floor surface (e.g., tile or hardwood). Facing the chair, place hands on the sides of the seat with straight arms. With a 90-degree angle between your hips and the floor, place your feet on a towel, balancing on the balls of feet with a slight bend in the knees. Pull your knees in toward elbows on a 4-count-in. Then, staying on the balls of feet, sliding your feet out on a 4-count to return to start.
To mimic the Supra's different incline levels, use a set of stairs to place your hands and different heights, keeping feet on a towel on the ground.