There are a million different sources of information on squat form and technique; search around and you can find numerous articles, instructional videos, pictures, and animations. Unfortunately these sources of information often advocate very different techniques, leaving readers confused. I do not want to claim to be the most knowledgeable person on squatting, but I have learned a lot on the topic in recent months. I want to share what I've learned in an attempt to clear up the conflicting information available.
The first thing to understand is that there is not just one acceptable style of squat. There are three criteria for a good squat: the lifter's weight stays back on the heels, the back does not bend, and the thighs reach a parallel position with the floor. Those requirements do not change, but there is more than one way to achieve them. When looking at squat positions, there are two indicative markers, the distance that the knees move forward and the amount of forward lean in the torso. The less the knees move forward, the more the torso will have to bend forward.
Olympic squat
In the world of elite lifters there are two styles of squats, the Olympic lifting and the powerlifting styles. Olympic lifters train for maximum weight in the clean and snatch exercises. A proper starting position for pulling the bar off the floor in these exercises features a torso positioned as close to vertical as possible. Also the clean finishes with a front squat, and the snatch finishes with an overhead squat, both of which require an upright torso. Thus Olympic lifters use a style of squat in which the torso is kept as vertical as possible for the entire movement. To achieve this, the hips drop straight down toward the ankles, and the knees are allowed to move as far forward as is necessary to get the butt and hamstrings to hit the calves. Olympic lifters squat this low, because they need to be able to drop as far down as anatomically possible to get under the bar during cleans and snatches. Some other features of an Olympic squat are a high bar placement on the shoulders and an arched upper back.Powerlifting Squat
On the other end of the spectrum are powerlifters. Their goal is simply to squat the most weight. The criterion that must be met for a legal competition squat is the thighs reaching parallel. A good powerlifting squat allows that to occur while moving the bar the shortest possible distance and utilizing the strongest possible biomechanical positions (minimizing knee and hip flexion). To achieve this the hips are pushed back instead of dropped, and the knees are kept directly above the ankles. In a shoulder width stance, this would require significant forward lean in the torso which places excessive load on the spine and lowers the bar almost as much as an Olympic squat. To combat this powerlifters use as wide a stance as their hip mobility will allow. Then when the hips are pushed back they can't actually move back as far, which means the torso does not have to lean as far forward. With this adjustment, the knees can stay high and the torso can stay more upright. It's the best of both worlds. The distance the bar has to move is reduced, the knees only flex to 90 degrees, and hip flexion is reduced too. Other features of a powerlifting squat are a low bar placement (below the spines of the scapulae) to reduce the load on the spine and an arched back to help account for that load. This manipulation of the squat movement allows the most weight to be lifted. An extreme powerlifting stance will be so wide that the torso can remain very close to vertical. This option is typically reserved for females; male lifters' hips do not allow the necessary joint positions.The extreme Olympic and powerlifting squats represent opposite ends of a spectrum. You do not have to choose one or the other; there are acceptable squat styles all along the spectrum. The key is combining the right characteristics together to get your weight back on the heels for the whole movement; that is the primary indication of a good squat style. Moving along the spectrum from the Olympic style (dropping the hips) to powerlifting style (pushing the hips back) requires using gradually wider stance with feet turned further out to ensure the knees track in line with the toes. The more the hips are pushed back, the more the torso will have to lean forward; reaching a torso angle of 45 degrees or lower should be accompanied by a low bar placement to reduce the load on the spine. Regardless of hip movement, keeping the torso as upright as possible is very important. What you don't want to do is combine pushing the hips back with a shoulder-width stance and a high bar placement. The result is a torso closer to horizontal than vertical; you can't expect to reach elite levels of strength putting that much load on your spine. It's also very difficult to keep your weight back on your heels. I have to confess that this is the style of squat I was originally taught, and I taught it to others. It took me years to realize the problems with it. Bottom line, if you can find a squat style that allows you to keep your weight back on your heels, that style is fine. It's hard to explain why this is so important. Rather than trying to get into the biomechanics, I just invite you to discover this truth for yourself. During the ascent of a squat, try to get to a point where it feels like you're going to fall backwards. Do that consistently, and you will understand why keeping your weight back is so important. The bar will go up much more easily, and you will feel much less stress on your back and knees.
Athlete Squat
Olympic lifters and powerlifters have their styles of squatting which best meet the demands of their sport, but what about the vast majority of athletes who don't compete in lifting? What about those who lift to enhance athletic abilities like agility, speed, and the vertical jump? The primary purpose of lifting weights for most athletes is not to get the highest possible weight or to mimic any particular movement; the purpose is to strengthen muscles and neural drive for use in athletic movements. With that in mind, athlete strength training should utilize full and safe range of motion, balance the development of opposing muscle groups, and interfere as little as possible with other aspects of training. What I recommend is a squat in which the focus is on dropping the hips rather than pushing them back. Let the hips move back naturally, but don't push them back intentionally. Also let the knees move forward naturally and don't worry about where they end up. Focus on keeping the torso upright and the weight on the heels. Use about a shoulder width stance and a high bar placement like an Olympic lifter. Also turn the feet slightly out to reduce the distance the hips move back. Following these instructions should result in a kind of midway squat between the two extreme styles. The knees will move about a little further forward than the toes and the torso will lean forward less than 45 degrees. For depth, get the tops of the thighs down to a parallel position with the ground. I do not recommend the "ass to grass" depth used by Olympic lifters; getting that low involves separation of the knee joint which over time will take the spring right out of anyone's legs. This style of squat evenly trains the quads and the posterior chain muscles. It uses wide range of motion in the knees and hips. And because of the upright torso, it does not require a ton of mass to be added to the torso to support the load of the bar. This midway style of squat allows for long-term, all-around strengthening of the muscles critical to athletic performance.As stated earlier, there are a number of good squat styles, and anything that keeps the lifter's weight on the heels can be used to achieve elite strength levels. The last point I want to bring up is the importance of being aware of your squat style and making training adjustments accordingly. If you use a quad-dominant squat style, make sure you include enough posterior chain work to keep your deadlift higher than your squat. Or if you use a powerlifting squat, you may not even have to train your deadlift for it to increase because the squats focus on the posterior chain. In this case, extra work for the quads should be included since the the squat style will develop them less. Also consider the demands of your sport. For example, basketball is a quad-dominant sport because of all the shuffling and change of direction; a basketball player certainly would not want to neglect the quads in training. On the other hand a sprinter may choose to focus more on the posterior chain in lifting, since those muscles drive the body forward during a sprint. However, remember maintaining balance between muscle groups is important.
Hopefully this article helps clear up some of the confusion about squat form and technique.
