Question on Form Breakdown in Squats and Maximal Loads

[Subsistence]

This may be a foolish question but I was curious about this. When it comes to form breakdown I usually see there as being 2 types:

1) Form breakdown that allows one to lift more weight
2) Form breakdown that causes one to lift less weight

Reasons for avoiding 1) tend to either i) be risk of injury (ex: round backed deadlifts), or ii) not targeting the proper muscle groups (cheat curl, kipping pull up). Reasons for avoiding 2) are obvious, and would include things like letting a press get out in front of you.

In squats I was wondering which type of error these would be:

a) GMing a squat
b) Knees collapsing in

It seems like both of these can happen when a lift gets really heavy. Is it the case that these form breakdowns can let one lift more, or less weight, on any given maximal attempt?

[Michael Wolf]

Your starting assumption is flawed: in our model, there are not form breakdowns that allow you to lift more weight. Correct technique in the SS model is also the most efficient technique, the one that allows the most weight to be lifted. You can often still make the rep if you push hard and grind it out, but the form breakdown that happens at max or near-max loads is not aiding your effort. I should note that this form can differ from what is defined at 'legal' in a powerlifting federation, and doesn't apply to lifts outside the SS model (more on that below).

The example of round back deadlifts is a good one. A lot of very strong pullers purposely round their thoracic spine to shorten the moment arm between their hips and the bar. This is not a form breakdown. It's a more advanced technique used by experienced lifters to lift more weight.

To answer your question specifically:
1. GM-ing a squat will always make it harder to lift. As the bar gets forward of mid-foot, that's an extra, unwanted moment arm you're fighting against in addition to the inherent moment arms in the movement.
2. For a squat as we define it, knee collapse will also make it harder to lift. In a front squat or high bar squat, where you're not rebounding off the posterior chain but off the knees and quads, this might help you get a bit more bounce out of the bottom.

[Michael Wolf]

In a heavy deadlift, it's easier to either:
A. Let your back round
or
B. Lower your hips down to the squat position (like many olympic lifters and coaches insist on doing for the clean and snatch) and set your back this way

But neither allow more weight to be lifted. So no, your body doesn't automatically conform to the position that allows the most weight to be lifted. Your body will sometimes do what's easiest or easier. You must tell it what to do. Command it to grow, if you will.

[dienster]

Knees cave in because the optimal position for maximum muscle recruitment needs to be trained. At max weights, maintaining that position is forgotten first when focusing on the heavy and that allows your knees to cave in resulting in sub optimal form.

Remember the squat teaching method. You HAVE to use your brain to keep them out. They don't necessarily want to go there.

[Subsistence]

In a heavy deadlift, it's easier to either:
A. Let your back round
or
B. Lower your hips down to the squat position (like many olympic lifters and coaches insist on doing for the clean and snatch) and set your back this way

But neither allow more weight to be lifted. So no, your body doesn't automatically conform to the position that allows the most weight to be lifted. Your body will sometimes do what's easiest or easier. You must tell it what to do. Command it to grow, if you will.

This seems very wrong to me. Most people I know can pull more with some back rounding than they can with their back perfectly in extension. The back is often a weak link, and more can be lifted without requiring a loss of extension to be a loss of a lift. Have you never seen someone start a pull, their back not be strong enough to maintain extension, but they still manage to complete the pull?

[patterson]

not to high Jack here, but why does it seem at heavy attempts on squats, many novice lifters want to GM their squat

[Michael Wolf]

Knees cave in because the optimal position for maximum muscle recruitment needs to be trained. At max weights, maintaining that position is forgotten first when focusing on the heavy and that allows your knees to cave in resulting in sub optimal form.

Remember the squat teaching method. You HAVE to use your brain to keep them out. They don't necessarily want to go there.

This sounds pretty good to me.

I was thinking about the first one. I understand it's a weakness of the hamstrings that does this, and it doesn't actually help you lift the weight.

In the set-up, yes. Or, if you set correctly but it happens during the lift, you either didn't focus enough on it or your erectors need to get stronger. Either way, it certainly didn't contribute to the rep being easier. The squishiness is a poor moment force transmitter, compared to erectors locked in extension.

Does this mean that any squat(in the style advocated by Rippetoe) that is performed with the knees caving in, can be performed at the same weight with the knees in the correct position, if the lifter simply focuses enough on it?

I don't want to say it as an absolute without more thought, but this strikes me as a correct statement.

sorry I can't edit my previous post, but something else I thought of, is all the big lifts that I've watched on youtube have always been with good, if not perfect, form. I never see knees buckling in powerlifting squat record attempted. Either they make the weight or they fail, but they never make a "form error" that doesn't cause them to lose the lift.

I guess this is evidence that what you're saying is correct.

Not sure I followed this.

This seems very wrong to me. Most people I know can pull more with some back rounding than they can with their back perfectly in extension. The back is often a weak link, and more can be lifted without requiring a loss of extension to be a loss of a lift. Have you never seen someone start a pull, their back not be strong enough to maintain extension, but they still manage to complete the pull?

Did you not read my first reply to your OP? The purposeful rounding of the thoracic spine is a technique used by already strong, more advanced lifters to lift more weight. Although rounded, their erectors lock them into that rounded position, so there's no squishiness in their ability to transmit moment force. This is entirely different than someone trying to maintain lumbar and thoracic extension, but losing it somewhere on the pull due to lack of focus, effort, or simply weakness. This is a loss of extension that introduces a squishy segment into the lift. Squishy segments do not transmit force as well as rigid segments.

[Michael Wolf]

not to high Jack here, but why does it seem at heavy attempts on squats, many novice lifters want to GM their squat

I suspect there are some differences in each case, but I've found a lot of people do this because in their focus on hip drive, they forget the other half of the equation, keeping their chest up.

[Subsistence]

Thanks for clarifying Wolf.

I have before heard that idea that in a GM'd squat, it is possible to shoot the hips without bringing the bar significantly forward. The resulting set of angles would then somewhat mimic a deadlift position (higher hips, more horizontal back) with the bar simply on your back opposed to in your hands. The concept being that force may be more easily exerted in the deadlift position (people do generally deadlift more than they squat), explaining why people often find themselves in this position when doing maximal effort squats.

Any thoughts on why this falls apart?

[Michael Wolf]

I don't understand how the hips can rise, the torso not rise along with it, yet have the bar not move forward relative to the mid-foot balance point as well as relative to the hip. The bottom of a low bar squat somewhat resembles a deadlift/pulling position, but if the hips shoot up, you have the good morning position - hence, why people call it "GM-ing your squat." The good morning is an exercise that purposely puts the bar forward of mid-foot and far away from the hips; it's an assistance exercise in large part because less weight must be used for this reason. So GM-ing a squat refers to the unwanted situation where you've somewhat replicated the joint angles of the GM - except you're trying to squat, probably more weight than you can GM, and thus have to struggle to complete the rep due to the unwanted moment arms.