Deeper Squats = better performance

In a recent study published in the European Journal of Applied Physiology, researchers found that doing deeper squats was superior to shallow squats. If you want greater increases in muscle mass and power, eventually you want to be able to get your upper thighs parallel or deeper. For those that lack the mobility to get deeper, quarter squats can still be beneficial, just not to the degree of deeper squats. Remember, it's a smart idea to master the movement with your body-weight before loading the movement with additional weight (med balls, dumbbells, barbells, etc.)
 

Study Reference:  Bloomquist K, Langberg H, Karlsen S, Madsgaard S, Boesen M, Raastad T. Effect of range of motion in heavy load squatting on muscle and tendon adaptations. Eur J Appl Physiol. 2013 Apr 20

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