Stand with feet shoulder width apart and toes facing in front of you. Keep dumbbells hanging by your sides or on your shoulders as shown in the pictures.
Keeping your back flat, slowly lower your body, bending at the knees and the hips. Stop when your legs form a 90 degree angle. Do not let your knees go forwards past your toes.
Slowly push through your heels to return to the starting position, contracting the thigh muscles.
Start with very light weight to perfect your form. If you feel any discomfort in your knees or lower back, stop doing this exercise.
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