Grip a single dumbbells firmly in your left hand and stand with your feet shoulder width apart. Move your right foot back until the toe of your right foot is in line with the heel of your left foot. With a slight bend in your knee, slowly hinge your hips back, inhaling as you do so and keeping a neutral spine. Focus the tension on your left leg whilst letting the right leg bend naturally and stay relaxed. Keep your arms extended and the dumbbell close to your thigh throughout. When your hips have hinged as much as possible, proceed to reverse the movement. Ideally you should not go further than 1-2 inches below the knee joint, otherwise you risk putting the load through your lower back and losing the tension in your hamstrings. Drive your hips forward with force, squeezing your glutes and hamstrings as you do so and exhaling. Pause for a count of one at the top, keeping your glutes tensed. Perform all the required reps on one leg before changing to the other.