A pistol is a one-legged squat that, yes, beats the hell out of your quads and glutes, but also puts your balance and core strength to the test. Start in a standing position with your back to the chair. Lift one foot off the floor, hinge at the hips, and slowly lower your butt toward the seat cushion. Extend the floating leg in front of you, using it to counterbalance your weight. Sit down as lightly as possible, maintaining tension throughout your body. Keeping just one foot on the floor, stand up again. If you have trouble standing, rock back slightly and use your body’s momentum to launch yourself back up.
Alternating legs, do three sets of 10 pistols on each leg.