There’s a lot of discussion out there about femur to torso ratio in the back squat: “long femurs.” I’m a certified personal trainer. The “bad levers” of femurs longer than torso for squatting get a lot of attention in training forums, but something gets very much overlooked: femur to shin ratio.
If you clicked on this article, there’s a good chance you know exactly what I mean when I say lightning bolt diagram. Now visualize two lightning bolt stick figures with equal torso and femur length, but the disparity is in tibia (shin) length. The first figure has ridiculously short shins and the second figure has these super long tibias.
What happens when they parallel squat? The figure with the short shin (make it abnormally short to better understand this) can’t get his feet under his hip bones. There just isn’t enough shin length to act as a “pedestal” for his squatting body.
Because his shins are so short, his feet are displaced far forward of his hips, requiring him to have an excessive forward lean – even though his femurs may be the same length as his torso or even shorter.
The second figure has no problem sitting down into a squat while his back stays closer to upright than folded over. Because there is more length in his shins, his feet are more under his hips. This means he doesn’t have to lean that far forward to get his shoulders over his feet. Think of his super long shins as supportive pedestals to just sit on.
The long femur in relation to short shin is a proportion that is not determined by overall body height. Thus, a very short person can have femurs several inches longer than their tibias, and a very tall individual can have shins four inches longer than their femurs.
Conversely, a 5’4” athlete can also have short stubby femurs, such that most of the leg is tibia, and a 6’7” athlete can be mostly femur. Overall body height is not a factor in the femur-to-tibia ratio. Torso length will vary and is not related to femur-to-shin ratio.
So if your femurs aren’t longer than your torso yet you fall backwards as your squat nears parallel, it could be due to not having long enough pedestals to support your body; short shins prevent the feet from getting far enough under the hips – the feet are displaced too far forward. So to get the shoulders over the feet, you must fold in half.
So how does someone with these levers do a back squat without folding in half? Widen the stance until you no longer must double over. The knees must track over the feet when squatting with a wide stance. Pointing the feet outward to 20-30 degrees will make the squat even more doable for someone whose shins are disproportionately short for the rest of their body.
Another trick is to wear a one-inch heel insert. Forget the expensive Olympic weight lifting shoes. I do not advise placing the heels on weight plates because this setup is not part of your person (like heel inserts would be), and furthermore, it’s a hassle to back up onto the plates.
Source: Based upon being a certified personal trainer since 2003