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Squat Theory and Execution

Written by “Arioch”





The squat should be a standard exercise in any lifters program. Whether the goal is strength, hypertrophy (increase in muscle size), increased accelerative ability, or a heightened vertical jump, the squat is the tool for the task. In addition to working the muscles of the legs, hips, lower back, abdomen, and obliques, the demands of squatting should stimulate a growth response from the body that will carry over into strength and size increases in other areas.

The basic technique of the squat consists in placing a loaded barbell across the shoulders, then bending at the hips and knees, descending into the bottom position, “the hole,” and returning to an erect position. We will examine the squat from the deck up.

Stance. This varies from individual to individual, but one thing is necessary for all who wish progress: you must keep your feet flat on the deck at all times. The center of gravity may be maintained over the center of the foot, but it is generally best to push through the heels. This will help in maintaining bar position and help eliminate a small degree of forward lean. To achieve this, some people find it necessary to curls the toes upward while squatting, forcing their heels flat. The feet should be placed at least shoulder width apart, and some individuals may best utilize a stance nearly twice shoulder width. The narrower stance tends to place more direct emphasis on the quads, and creates a longer path for the bar to travel. The wider stance (often called “sumo”) tends to be favored by many powerlifters, although some have enjoyed great success with a relatively narrow stance. The sumo stance place more emphasis on the adductors and hamstrings. As a rule of thumb, lifters with longer legs will need a wider stance than shorter individuals. However, there are exceptions. A wider stance will tend to recruit both the adductors and buttocks to a greater degree than a narrow stance. (1)

The shins should be a close to vertical as possible throughout the entire movement. This lessens the opening of the knee joint, and reduces the shearing force as well. By reducing the workload that the knee joint is required to handle, more of the work is accomplished by the larger muscles around the hip joint. For powerlifters, this decreases the distance one must travel with the bar, as the further the knee moves forward, the lower the hips must descend to break parallel.

There are several schools of thought on squat depth. Many misinformed individuals caution against squatting below parallel, stating that this is hazardous to the knees. Nothing could be further from the truth. (2) Stopping at or above parallel places direct stress on the knees, whereas a deep squat will transfer the load to the hips,(3) which are capable of handling a greater amount of force than the knees should ever be exposed to. Studies have shown that the squat produces lower peak tibeo-femoral(stress at the knee joint) compressive force than both the leg press and the leg extension.(4) For functional strength, one should descend as deeply as possible, and under control. (yes, certain individuals can squat in a ballistic manner, but they are the exception rather than the rule). The further a lifter descends, the more the hamstrings are recruited, and proper squatting displays nearly twice the hamstring involvement of the leg press or leg extension. (5,6) and as one of the functions of the hamstring is to protect the patella tendon (the primary tendon involved in knee extension) during knee extension through a concurrent firing process, the greatest degree of hamstring recruitment should provide the greatest degree of protection to the knee joint. (7) When one is a powerlifter, the top surface of the legs at the hip joint must descend to a point below the top surface of the legs at the knee joint.

Knee injuries are one of the most commonly stated problems that come from squatting, however, this is usually stated by those who do not know how to squat. A properly performed squat will appropriately load the knee joint, which improves congruity by increasing the compressive forces at the knee joint. (8,(9) which improves stability, protecting the knee against shear forces. As part of a long-term exercise program, the squat, like other exercises, will lead to increased collagen turnover and hypertrophy of ligaments. (10,11) At least one study has shown that international caliber weightlifters and powerlifters experience less clinical or symptomatic arthritis. (12) Other critics of the squat have stated that it decreases the stability of the knees, yet nothing could be further from the truth. Studies have shown that the squat will increase knee stability by reducing joint laxity, as well as decrease anterior-posterior laxity and translation. (13,14) The squat is, in fact, being used as a rehabilitation exercise for many types of knee injuries, including ACL repair. (15)

One of the most, if not the most critical factor in squatting is spinal position. It is incredibly important not to round the back. This can lead to problems with the lower back, and upper back as well. The back should be arched, and the scapulae retracted, to avoid injury. This position must be maintained throughout the entire lift, as rounding on the way up is even more common than rounding on the way down, and people who make this mistake are the ones who perpetuate the “squats are bad for your back” myth. Furthermore, spinal position is essential to maintaining a proper combined center of gravity (CCOG). The farther one leans forward or, even worse, rounds the back, the more strain the erectors are forced to bear, and the less the abdominals can contribute to the lift. To say nothing of the fact that the greater the lean, the greater the shearing force placed on the vertebrae. Proper spinal alignment will assist in ensuring that the majority of the force the spine must bear is compressive in nature, as it should be. Another reason for descending below parallel is that the sacrum undergoes a process known as nutation (it tilts forward, relative to the two ilia on either side of it). At only 90 degrees of knee flexion, the sacrum is still tilted backward, which inhibits proper firing of the erectors and gluteus maximus and minimus. Going through a full range of motion completes the rotation of the sacrum and allows maximal muscular recruitment.

“Squats are bad for your back” is yet another cry of the weak of both leg and spirit. While an improperly performed squat can cause problems, so can improperly performed barbell curl, yet many of the people who use the squat rack only to curl do not seem to have a problem strengthening their elbow flexors. While the squat can be hazardous to the back among the untrained who often incline the torso to an unsafe degree, as well as round the back, skilled athletes have been shown to minimize trunk segment torques by maintaining a more erect posture. (16) It has been positively shown that maintaining an upright torso during the squatting motion reduces both spinal compression and shear forces. (17) Several studies have shown that weightlifters experience not only less back injury and pain that many other athletes, but often even less than inactive individuals, which clearly displays that a proper weight training program, which includes squatting, is beneficial in avoiding injury. (18,19)

The placement of the bar is another very important consideration when squatting. If one places the bar high on the traps, more emphasis will be placed on the quads, and a low bar squat recruits more of the lower back and hamstrings, by virtue of back extension, simply because the lower the bar is placed, the greater the degree of forward lean. Even when high bar squatting, the bar should NEVER be placed on the neck. This is far more stress than the cervical vertebrae should be forced to bear. When a powerlifter squats with a low bar position, the bar should be placed no lower than three centimeters below the top of the anterior deltoids. For other lifters, comfort and flexibility will go a long way towards determining bar positioning. When gripping the bar, at first it is best to place your hands as close together as possible, to maintain tension in the upper back, and to avoid any chance of the bar slipping. As a general rule, the lower you place the bar, the wider your hands will have to be. Anything placed between the bar and the lifter, such as a pad or towel, decreases the force of friction and increases the chance of the bar slipping. It is to avoid injuries that this practice is banned in competition. Also, this will artificially raise the lifter’s CCOG, which makes it harder to balance under a heavy load.