Belted squats for developing abs

[Charlie Davies]

Rip, I've always had trouble understanding your analysis for why belted squats develop abs better than beltless squats.

But recently in a thread down in repetetive inquiries, I came up with my own wording of it that finally makes sense to me. I'm sure this will sound obvious to you, but it's the first time I've understood it. So maybe someone else will find it helpful.

1) Rectus abdominus isometric contraction will turn into concentric contraction, if lumbar flexes. I.e. limit of max isometric r.a. contraction is resistance to lumbar flexion.
2) The belt holds abdominal pressure, stiffening the torso against flexing.
3) Thus max possible r. a. isometric contraction is increased by the belt.

No mention of ab muscle thickness, proprioception, or muscles pushing on things. Simple mechanics.

But let's test the theory! I just put on my belt and attempted an ab crunch with valsalva. The belt & valsalva resisted my lumbar flexion, and I could bear down on my abs really hard.
The belt turned my crunch into a supine plank, with the belt taking the place of bodyweight/the ground for providing resistance.

[Mark Rippetoe]

1) Rectus abdominus isometric contraction will turn into concentric contraction, if lumbar flexes. I.e. limit of max isometric r.a. contraction is resistance to lumbar flexion.
2) The belt holds abdominal pressure, stiffening the torso against flexing.
3) Thus max possible r. a. isometric contraction is increased by the belt.

I think you mean "extension" here.

[mrflibble]

cwd, as I understand your explanation, it appears you believe that when we brace the abdominals in an isometric contraction, we're actually attempting a concentric contraction which the belt resists and passively forces us to contract isometrically instead.

I do not agree at all. I'm certain you are not just mistaken, but proposing something that could actually be harmful. What you describe would require relaxation of the spinal erectors (which of course must lengthen during an "ab crunch"). This is the last thing you need when trying to support a heavy barbell.

The abs (and erectors) contract isometrically simply because we have control over our bodies and choose to do so. We don't need the belt to "trick" an attempted concentric contraction into an isometric.

No mention of ab muscle thickness, proprioception, or muscles pushing on things. Simple mechanics.

Ignoring these things because you want it to be more simple than it really is doesn't make them no longer true or relevant. Whether you want it to be true or not, the belt does provide a proprioceptive cue, the ab muscle bellies do expand during an isometric contraction (both inwards, and outwards - hint: unless something stops it). These provide the correct explanations for belt use.

I know Adam quoted from Rip's article before, but perhaps you missed it. It's worth quoting again because it explains things so clearly that I honestly struggle to understand why that didn't settle the issue then and there:

The belt provides a restriction to the outside diameter of the gut, and "hoop stress" (like the force applied to the iron hoops of a wooden barrel by the liquid inside) is applied around the circumference of the trunk outward and distributed across the whole belt more or less evenly. When the abdominal contraction occurs, the slightly expanding muscle bellies can only expand inward due to the restricting "hoop tension" of the belt, which increases the pressure in the gut.

http://www.t-nation.com/training/the...d-the-deadlift

[Charlie Davies]

Rip, I meant flexion. If this is wrong, it was deliberate :-)

mrflibble, of course I don't propose we should flex our backs during a squat. I've read Rip's article about belts and deadlifts carefully more than once. Yes the mechanics of the belt + valsalva in the squat are more complicated than I can easily analyze. And of course proprioception is a factor, that's why I use a belt for my presses (though to avoid over-extension in that case).

I'm looking for an intuitive explanation of what makes a harder isometric "abs" contraction possible with a belt than without. One limiter of isometric contraction is that whatever resists that contraction has to not move, or it's not isometric.

I think muscle bellies thicken as they shorten and thin as the lengthen, because conservation-of-volume. I would think an isometric contraction of the abs would not thicken the muscle belly very much.

[mrflibble]

mrflibble, of course I don't propose we should flex our backs during a squat.

Even though you did not intend to, you did, as this would be a side effect of your understanding of the belt resisting attempted lumbar flexion.

And of course proprioception is a factor, that's why I use a belt for my presses (though to avoid over-extension in that case).

How do you think it does this? Do you believe the belt physically prevents excessive lumbar extension? (The same way you think it prevents flexion in a squat). If so, you are mistaken. The belt does help - by allowing a stronger isometric contraction of the rectus abdominis.

I'm looking for an intuitive explanation of what makes a harder isometric "abs" contraction possible with a belt than without. One limiter of isometric contraction is that whatever resists that contraction has to not move, or it's not isometric.

Why do you need more reason than proprioception? Contact helps awareness. I can contract my TFL if I stick my thumb into it, without, I can barely find it.

I would think an isometric contraction of the abs would not thicken the muscle belly very much.

It doesn't need to. "Not very much" is still enough. The belt also ensures maximum impact of the "not very much" by directing it all inwards, instead of both in and out.

[Alex Kershaw]

Rip, I meant flexion. If this is wrong, it was deliberate :-)

mrflibble, of course I don't propose we should flex our backs during a squat. I've read Rip's article about belts and deadlifts carefully more than once. Yes the mechanics of the belt + valsalva in the squat are more complicated than I can easily analyze. And of course proprioception is a factor, that's why I use a belt for my presses (though to avoid over-extension in that case).

I'm looking for an intuitive explanation of what makes a harder isometric "abs" contraction possible with a belt than without. One limiter of isometric contraction is that whatever resists that contraction has to not move, or it's not isometric.

I think muscle bellies thicken as they shorten and thin as the lengthen, because conservation-of-volume. I would think an isometric contraction of the abs would not thicken the muscle belly very much.

Do you have an intuitive explanation as to why you can make a harder contraction of your quadriceps and glutes with a heavy barbell on your back than without?

[Charlie Davies]

mrflibble, yes the Muscle-Belly-Thickening-of-the-Abdominal-Muscles-due-to-isometric-contraction-during-Valsalva (let's abbreviate this to MBTV) is real, and valuable. You and Rip feel it is significant, I suspect it's a small effect. But I'll take it on authority that you're both right until someone actually measures it.

But MBTV is beside my point anyway, since I'm not arguing against the benefits of belting our squats. I'm pro-belt! I belt every squat set over bodyweight, I have a dodgy old spine.

Back to my point: the belt resists abdominal expansion, allowing greater pressure during valsalva, and this pressure has many effects. As Rip was probably alluding to in his first reply, one is to support the lumbar spine anteriorly, resisting over-extension. Which I'm not disputing.

My claim involves another effect of abdominal pressure -- it stiffens the torso in general, against bending in any direction.

In the "repetetive inquiries" thread I linked to earlier, someone (not me!) advocated planks as assistance, especially for those who belt their squats and thus supposedly have underdeveloped abs.

I'm just tickled to have (I think) come up with an argument why Rip's assertion that belted squats permit a harder isometric abs contraction is true. My argument may be incorrect, but it means well.

[CJ Gotcher]

Whether you want it to be true or not, the belt does provide a proprioceptive cue, the ab muscle bellies do expand during an isometric contraction

Mrflibble, I'll agree with you that the belt provides a proprioceptive cue to the muscles of the abdominal belly. I'll also agree that you can generate additional hoop pressure with a belt than without. I'm not convinced that this happens because the ab muscle bellies push outwards or expand when they contract (it sounds like an oxymoron).

When I conduct an isometric contraction of my abs without taking an inbreath, the contraction brings the entire belly slightly closer to the spine- not out towards where a belt would be (try it yourself- I might be weird). The same is true (to a lesser degree but still true) after I complete an inbreath- tightening my abs pulls the body of my belly very slightly closer towards my spine. I suspect the hoop pressure is formed because the belt resists the expansion of the belly caused by the intake of air, not because the abs expand. After the abs contract, if the belt is still stretched beyond its original diameter, it wil continue to provide hoop pressure, which is transferred through the 'fluid ball' to the ab muscles and the spine.

[spacediver]

Suppose you're lying flat on your back, with a collapsed building on top of you. You are slowly dying, but you decide to fit in one more lifting session before you expire. A large slab of concrete is resting on you, and you move your arms into position as if to bench press the weight off your body. You press with all your might, and the slab doesn't move at all. Because of this, your muscles are isometrically contracting. Impressed with your efforts, the gods of steel reward you by teleporting you out of the building, and after a full recovery, you try to recreate that intense isometric experience, but this time without any weight resting on you. Instead, you just lie flat on your back, get into that same bench position, and isometrically contract for all your worth.

If I understand the OP, the notion is that the contraction in the first scenario is stronger than that in the second.

Given that when the abs concentrically contract, the torso flexes, then the question is whether flexing the torso against immovable resistance is equivalent to isometrically contracting the abs, while, for example, doing a squat. And further, whether the belt functions to resist torso flexion in such a manner.

[Charlie Davies]

Given that when the abs concentrically contract, the torso flexes, then the question is whether flexing the torso against immovable resistance is equivalent to isometrically contracting the abs, while, for example, doing a squat. And further, whether the belt functions to resist torso flexion in such a manner.

Right. This is a fairly silly discussion, I know. But I'm a nerd, and there's room for silly discussions on the internet. Rip can move this thread if/when he gets tired of it.

I tested my theory by attempting an ab crunch with the belt + valsavla. It become something like a supine plank, i.e. an isometric exercise. I'm not saying supine belted planks are a useful exercise mind you...