The lateral dumbbell step-up builds strength in the legs, specifically the quads, hamstrings, and glutes. The exercise also improve balance and stability on both sides of the body.
Stand beside a low box or bench. Hold a dumbbell in each hand at arms length, hanging by your sides. Place one foot onto the box or step, while your other foot is firmly planted on the floor.
Press heel of foot into the box and drive upward until your supporting leg becomes completely extended. Finish with your trail leg on the box or bench. Step down with the trail leg to return to starting position.
Center your weight in your heel and mid-foot.
Avoid using too high of a box from the start. Begin with a box of a moderately challenging height and progress from there.
Be sure to drive through your heel and squeeze your glutes at the top of the exercise.