Last week, we talked about ankle dorsiflexion and how it plays a huge role in squat mechanics. We ended on the idea that some people may just have bad dorsiflexion anatomically. This week, we are continuing with this theme of things beyond our control in terms of our bodies: our ratios. This is in regards to length ratios and how torso length, femur length, and tibial length all effect our squat mechanics.
Let’s say you and two friends are working out together and you all decide to do barbell squats. Your one friend doesn’t mind squats, your other friend loves doing them, and you absolutely despise them because they irritate your low back, but you’re a good sport and squat regardless. All three of you are the same height, with the same torso length, with adequate ankle dorsiflexion and are squatting to parallel because you’re competing in a powerlifting competition together, which is one aspect the judges will score you on, and are looking to hit the same heavy squat among the three of you. But, your legs are slightly different between the three of you. Your friend who doesn’t mind squats has a 1:1 femur to tibial length ratio, your friend who loves squats has a 1:2 ratio, and you, who hates squats, has a 2:1 ratio. The figures below demonstrate how each of your squats are going to look different according to a competition judge as well as feel different between each of you.
Your friend who doesn’t mind squats with a 1:1 ratio can hit proper depth with relative ease, not too much strain on their back and depth is appropriate. Your other friend who loves squats with a 1:2 ratio can hit proper depth with extreme ease, hardly moves the bar to hit that depth, and barely looks like they’re trying. You on the other hand, with a 2:1 ratio, have difficulty hitting proper depth, appear to squat the deepest, move the bar the furthest, and it bothers your low back. This is because as you perform the squat, your femur is twice as long as your tibia. Even with adequate dorsiflexion, in order to maintain a neutral bar path, your hips are pushed further away from the center of gravity. This creates a moment arm across the hips that is significantly higher than your two friends. The further the hips, move from the center of gravity, the greater the moment arm. The greater the moment arm, the heavier the weight being squatting will feel across the hips and low back. As shown in the diagram, you
put yourself in a compromised position in order to hit depth. Due to the fact you are practically leaning forward to hit depth, your low back will take a larger load than either of your two friends.
It’s simple to see how these length ratios play a role in squat mechanics. In this specific example, a lot of variables were kept the same, such as lifter height, torso length, ankle dorsiflexion, and load squatted. And obviously the ratios are a bit extreme. But what if you had extremely long femurs compared to tibias, how can you help make squatting easier and safer? For one thing, we want to maximize dorsiflexion. Beyond that, shoes with a slight heel lift will mimic having a greater degree of dorsiflexion. Additionally, you can externally rotate your feet slightly. When I say slightly, I mean 10-15 degrees. This will allow your center of gravity to remain more inline with the center of gravity of the load your using and decrease the moment arm across the hips somewhat. In addition to externally rotating your feet slightly, you can widen your stance slightly as well. Sometimes, placing your feet slightly outside of shoulder width can make a huge impact on how the squat feels. Another option would be placing the bar in different location across your shoulders.
As such, despite the fact you may not be necessarily built to be a great squatter, it does not mean, you can’t adapt to improve what is already there.