How Hip Anatomy Affects Squat Mechanics

ahorschig

8 years ago

As coaches we often have a standard set-up for teaching the barbell squat. Toes should point out slightly, feet should be placed at shoulder width and everyone should squat below parallel. Unfortunately this doesn’t always work. No two people will squat exactly the same way. There is no “one size fits all” approach to squatting.

Before we start, it should be said that this is not the first time this subject has been discussed in depth. Dr. Ryan DeBell of The Movement Fix wrote a great article previously that discussed how hip anatomy can easily differ between people. At Squat U we are trying to complete a comprehensive guide to squatting. Some of you have read Dr. Debell’s article, however many of you have not. Omitting our take on hip anatomy would be a disservice to people who want to learn more about squatting.

There are two main factors that dictate how well we squat.

Mobility – the pliability of our soft tissues (muscles and fascia) and how it affects how we move. When our tissues become stiff or shortened, they can hinder our ability to move well. This is one of the reasons why sitting for 8+ hours a day is so harmful to the body.
Anatomy – the way our bones are formed and aligned. It shouldn’t come as a surprise that you have a different bone structure than your best friend (or anyone else for that manner).

We have previously addressed hip mobility in one of our past articles. By addressing stiff tissues we can easily improve our technique. For this reason, “mobility” has been has become a popular buzzword in recent years.

However for some individuals, they just can’t seem to perfect the ass-to-grass squat or achieve a flawless pistol squat no matter how hard they try. For some people, no amount of mobility work will change their squatting mechanics. When an athlete has a problem with their squat due to their anatomy, they will always be fighting an upward battle. This will be apparent when we have a closer look at the hip joint.

Anatomy 101

The hip is basic ball-and-socket joint. The end of our thigh bone (femur) is shaped like a small ball. It fits within the “socket” (acetabulum) of our hips.

Individual Differences (Hip Socket)

However, not everyone fits this “textbook” bone structure. Variations in the way our hips are formed will impact how we move, especially with the squat.

In 2001, a group of researchers from Japan took a close look at the hip joint. While a large majority had “normal” hip sockets, close to 40% of those examined did not (1). Let’s take a look at a few photos that show how dramatic these differences can be.

In this photo you can see two totally different socket shapes. The socket of the left hip points forward and has a sharp angle. On the right, the socket opens laterally and has a curved shape. According to research, there are actually 4 distinct shapes the socket can take (1).

Now take a look at the hips from the front. With this view, you can see again a dramatic difference in the alignment of the sockets. The hip on the left has the sockets pointing forward meanwhile the hip on the right opens more laterally. This difference alone will have a significant impact on how a person squats.

Individual Differences (Femur Shape)

Some people also have variations in the way their femurs are shaped. For example, some of us have femurs that are twisted forward or backward. This will affect the alignment of the femur in the hip joint. A more angled femur (right) is called an anteverted hip. A flattened angle (left) gives us a retroverted hip (2).

What is anteversion?

In order for a femur with an excessive angle to fit correctly inside the hip socket, the rest of the thigh must be rotated inwards. For this reason, athletes who have this type of hip will appear as if they have an excessive amount of internal rotation and a little amount of external rotation.

While some athletes with anteversion will show the classic “pigeon toes” alignment, this isn’t always the case. In order to keep their toes from pointing inwards the lower leg bones (tibia) will often adapt. The tibia will form an outward twist to compensate for the inward twist of the femur. The body adapts and tries to keep the feet pointing forward when possible.

For this reason, it is very hard to know if someone has a natural twist in their bones by just looking at them. Forcing an athlete to conform to the ‘ideal’ squat technique when they have this type of anatomy can be disastrous. If an athlete reports feeling uncomfortable with their squat stance no matter how much mobility work they do, they should be screened to see if their anatomy is preventing their progress.

How to Screen

Checking the hips often starts by assessing the amount of rotation available at the joint. With an athlete on their back it is easy to see how much internal rotation (foot moving away from the body) and external rotation (foot moving toward the body) an athlete has.

While this is a great way to assess possible mobility restrictions, it doesn’t give us a great idea of what’s going on with our bony anatomy. If there was a large difference in the amount of internal vs external rotation on the same leg we need to assess what’s going on inside the hip joint. To screen the anatomy of our hip we need to use Craig’s Test.

Start with the athlete lying on their stomach with their knees bent at 90°. Take your hand and feel for the where the notch of the femur (greater trochanter) is located. With your other hand, begin rotating the athlete’s lower leg in and out. As you rotate the leg you’ll begin to notice the notch of the femur becomes more and less prominent against your hand. Stop moving the lower leg when you find this position to be most prominent.

Ideal or ‘normal’ anatomy will leave the lower leg pointing only slightly away from the body (within 15° from a vertical position). If the athlete has their lower leg now positioned at a large angle, they have a possible anteverted hip. This method of assessing hip anatomy has been shown in research to be extremely reliable (even better than taking an X-ray) (3).

What Now?

If you have a positive Craig’s test you may be asking yourself, “What does that mean for my training?” Individual differences in anatomy like this will affect both foot angle and width of your squatting stance.

Some athletes can naturally squat with a wide stance. Others (especially those with hip anteversion) will have to squat with a narrow stance. Some athletes will be able to squat with their toes straightforward and others will have to turn their toes out at an angle in order to reach full depth.

An athlete’s stance should be dictated therefore by comfort. They need to feel stable with whatever stance they take and they should not have a pain. Athletes who try to conform to a squat stance that is not right for their hips will feel a hard blocking sensation or a pinching pain in their hips that is unrelieved with mobility work. This is your body telling you to move differently. Listen to it.

Conclusion

If you have excellent squat form, congratulations. However, if you struggle to perform a squat with perfect technique (even after hours upon hours of mobility work) it may not be your fault. Some of us are born with the ideal skeleton for deep squats. Some of us are not. Just because anatomy may not be on your side doesn’t mean you should just hang up your weightlifting shoes and quit trying all together. You only need to understand what works for your body and make the right adjustments in order to reach your potential and stay pain free,