Another exercise I like to pair up in a superset. This is a secondary exercise, the primary being a compound exercise like a squat. The point of these lunges is to keep constant tension on your legs throughout the entire set. Try it without the weight first. Do a lunge, keeping your upper body upright, bringing the leading knee few inches shy of touching the floor. Then with your back foot, transition forward, but the trick is you can only come up a few inches, so you quickly shift the back foot forward into your second lunge. Pause at the bottom of the movement for a full second.