Begin standing with your feet hip-width apart, core pulled in toward your spine. Hold a dumbbell in each hand, palms facing in.
Keeping your feet shoulder-width apart, step your right foot back with control and land softly on your toes. Bend both knees to lower into a lunge, lowering your right knee as close to the floor as you can without touching. Your left knee should stay in line with your toes, bringing your left thigh about parallel to the floor or as close to that as you can get. Both knees should be at 90-degree angles. Keep your back straight and core tight, keeping the weights directly below your shoulders.
Drive through your left heel and push off your right toes to straighten your legs, simultaneously stepping your right foot back to return to the starting position.
This counts as one rep. Complete 15 reps, alternating legs.