Knee position during squat ascent

[Vegard Hennestad]

Hi, Mark

After developing what you referred to in SS as "an interesting type of tendinitis" in the knee, I found it necessary to further educate my dumb ass about squat technique.

I've been reading through the forum like a good little puppet, and especially found the TUBOW discussions useful. However, while the knee position during the descent into the squat has been explained in excruciating detail, both by yourself and your loyal disciples, I have yet to find the answer to this:

In the optimal squat, does the knee position, which is established between 1/3- and 1/2-way down into the hole, also stay the same during the ascent? I present the two possibilities:


1. The knee position stays the same, and just like the hips move back a bit during the descent to facilitate the fixed knee position, they move forward a bit during the ascent for the same reason. During TUBOW practice, the knees will (optimally) be in contact with the block until you are 1/2- to 1/3-of-the-way up.

2. The knees move backwards a bit so that the hips can rise up vertically.


As a follow-up question, if #1 is the optimal path, should the rest of the ascent also be identical to the descent? If you were to record yourself during this optimal squat, and then play it backwards, would it be indistinguishable? (besides the movement speed, of course)

I apologize if this appears as an attempt to split hairs, but I am (like you, I imagine), interested in the small details and technicalities of the lifts.

Sincerely, a Dumb-Ass

[Mark Rippetoe]

From this article: Squat Mechanics: A Deep Analysis | T Nation

I shall reiterate: The correct application of the hip-drive model entails assuming the correct back angle and knee position for the bottom of the squat by the time you're about half-way down, and holding it as constant as possible until you get back to that position on the way back up.

Nearly constant: the initiation of the movement out of the bottom with the hips will look like a very small change in back angle as the hips lead out of the hole. This is actually produced with a very slight knee extension.

Hip-bone's connected to the knee-bone, as it were, and if the hip comes up a little, the knee will have moved back, a little. This slight knee extension is essentially a quadriceps contraction, an obviously important part of the squat, but you think about it proximally even as it is a distal action.

Thinking about leading straight up with hips instead of thinking about extending the knees is the important thing going on in the lifter's mind that keeps the motion from turning into a good morning, which happens sometimes when the lifter moves hips back instead of up, and the knees have extended excessively.

[Vegard Hennestad]

Thank you! I'm terribly sorry I didn't find this before!

[sciomako]

Hi Rip,

I don't think your analysis from the T Nation snippet is discussed in SSBBT. That leads to a question: does it mean it is okay to have a slight forward bar movement (towards to the toes) when initially driving out of the bottom?

[Mark Rippetoe]

This essay is more recent than the material in BBT3 in its current printing. Done correctly, there will be no forward movement of the bar out of the bottom of a squat, because the change in back angle is kept under control.

[Scaldrew]

"Defaulting into a goodmorning" is an interesting subject because I've made that mistake in the beginning of my lifting endeavours. The advice I found online was advice I took to heart and only recently have begun to found incredibly stupid. What the fitness gurus are saying is that, if your hips rise and torso falls, you have "weak quads" and you need to address that by doing quad work. But if rising hips at the cost of a declining torso is caused by weak quads, why then are your knees more extended than they would be if your torso was remaining upright relative to the hips? Shouldn't "weak quads" look like a dead stop in the hole followed by a bailed attempt because the knees could not extend? If anything the hips are the "weak component" because the hip angle remains constant while the legs straighten out. And isn't a goodmorning a back and hip exercise with practically zero knee involvement? Why would "defaulting into that kind of movement" mean your quads are weak when that movement you're "defaulting into" relies specifically on the components that "are stronger than the quads" for its execution, namely the hips and back? Is everyone blind and stupid?

Which leads me to my next point: is everyone blind and stupid?

[Mark Rippetoe]

What the fitness gurus are saying is that, if your hips rise and torso falls, you have "weak quads" and you need to address that by doing quad work.

It's hamstrings. Hamstrings control the back angle.

Which leads me to my next point: is everyone blind and stupid?

Lots of them are.

[Scaldrew]

You'd think with their fitness guru status, they'd know about tiny anatomical details like that. You'd be wrong in thinking that.

Reeks of the PT approach, too, the whole "fix weaknesses by doing other exercises" approach.

[spacediver]

From this article: Squat Mechanics: A Deep Analysis | T Nation

I shall reiterate: The correct application of the hip-drive model entails assuming the correct back angle and knee position for the bottom of the squat by the time you're about half-way down, and holding it as constant as possible until you get back to that position on the way back up.

Nearly constant: the initiation of the movement out of the bottom with the hips will look like a very small change in back angle as the hips lead out of the hole. This is actually produced with a very slight knee extension.

Hip-bone's connected to the knee-bone, as it were, and if the hip comes up a little, the knee will have moved back, a little. This slight knee extension is essentially a quadriceps contraction, an obviously important part of the squat, but you think about it proximally even as it is a distal action.

At the bottom of the squat, I'm having problems visualizing how a quadriceps contraction can cause the knee to slide back, even a little bit. The only way the knee can move backwards or forwards is if the net moment at the ankle joint is above zero. As far as I can tell, there are only two things that can contribute to a positive moment about this joint, such that the shank rotates backwards, in the context of the squat.

1) The centre of mass is posterior to the ankle joint
2) Enough tension is generated by the muscles of the calf, which can react against the calcaneus (which itself is held in place by the force of friction between the foot/shoe and ground).

Contracting the quadriceps while the foot is anchored to the ground will result in knee extension via the femur rotating upwards about the knee, without any change in shank angle. Any tension in the quads that doesn't contribute towards this rotation will be experienced as compression in the femur.

The only way I can see the knees sliding backwards is if the COM changes in favour of this and/or the calf muscles exert enough tension.

My understanding of statics is evolving slowly, so I'm not as confident as I'd like to be with this analysis. Is there anything wrong with it that you or anyone else can see?

[Mark Rippetoe]

The only way the knee can move backwards or forwards is if the net moment at the ankle joint is above zero. As far as I can tell, there are only two things that can contribute to a positive moment about this joint, such that the shank rotates backwards, in the context of the squat.

1) The centre of mass is posterior to the ankle joint

I don't know what this means.

Contracting the quadriceps while the foot is anchored to the ground will result in knee extension via the femur rotating upwards about the knee, without any change in shank angle. Any tension in the quads that doesn't contribute towards this rotation will be experienced as compression in the femur.

If the quads extend the knee, and you drive the hips up out of the bottom, the combined tension of distal hamstrings and proximal gastrocs will pull the knees back a little bit.