Grab a pair of dumbbells at your sides, with your arms straight and your palms facing toward each other.
Stand in front of a bench or a box and place one foot, flat, on top of it. The step should be high enough that the thigh of the working leg is at least parallel to the floor. Draw your shoulders back and down, and brace your core before starting.
While maintaining an upright posture, press down into the step through your heel until your left leg and hips are fully extended. Gently touch the box with the other foot before reversing the motion.
Lower yourself down under control until your back foot reaches the ground, keeping your front foot planted on the box.
Make sure you are in the proper starting position before attempting another repetition.
Complete all the repetitions on one side, then switch sides and repeat.