Start standing with the stairs on your right side, about two feet away from the bottom step. Place your right foot on the bottom step.
Keeping your core pulled in toward your spine and your chest lifted, bend at your right knee, ensuring that your knee remains in line with your toes. Bend until your right thigh is parallel with the floor, with your back at a 45- to 90-degree angle to your hips. Your left leg should be straight. (If you can't straighten out your left leg, come back to the starting position and step farther away from the step.)
With most of your weight on your right leg/foot, push through your right heel to come to a standing position with your right foot still on the step. This counts as one rep.
Complete for 12 to 15 reps, then repeat on your left side.