Spanish Squat

Loop a band around something solid behind your knees, then hold the other end taut in front of you or step back until you feel real tension. Lean back into the band so it's supporting some of your weight, feet flat, torso upright. Bend your knees and sit down and back as if into a chair, letting the band tension increase as you lower and pull you back to standing. Your torso stays close to vertical throughout rather than hinging forward — the band takes over the role your hips would normally play in a regular squat, shifting almost all the work onto your quads. You don't need full depth here; going as low as you can while keeping tension on the band is the point.