One-legged moves can go far to balance out the right and left sides of the lower body. They keep you honest. To prevent injury, go easy in the beginning, start with one set and gradually work your way up to three sets. To maximize benefits, complete all sets on one leg and then go on to the other. Also, start your one-legged exercises on the weaker leg, and then work your stronger leg.
In addition to balancing out both sides of the body, single-leg (unilateral) exercises work the deep lateral stabilizers of the hip and core (i.e., gluteus medius and quadratus lumborum) in ways we can’t duplicate with bilateral moves. There’s also more carryover to normal ground-based movements like walking, skipping and running than you have with bilateral exercise. Try adding a few of the following exercises into your regular weight-training regimen for better balance and greater strength and for an overall body toning.