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PostPosted: Wed Feb 29, 2012 10:26 am 
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chances are most of you would have read this article anyway, but here's an excerpt from the new Bret Contreras article on t-nation.

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It's been said that "abs are built in the k-word." Research shows that the notion of spot-reduction for the abdominals is indeed a myth (Vispute et al. 2011). So if you're looking to have nice abs, focus on getting lean through diet and general strength training.

However, there are certain individuals who seek to maximize the muscularity of their midsection, and these folks are often interested in targeting the upper or lower abs.

My EMG experiments have shown that it's indeed possible to shift the emphasis toward the upper or lower abdominals depending on the exercise. If you're seeking increased upper abdominal activation, perform trunk flexion exercises with a fixed pelvis such as a Swiss ball crunch.

But if you're seeking increased lower abdominal activation, perform abdominal movements that posteriorly tilt the pelvis such as a reverse crunch. Or you could go with a "pillar chin up" where you prevent the pelvis from anteriorly tilting during a chin up, or an RKC plank (highlighted in the last installment of The Contreras Files).

The lower abdominal EMG and posterior pelvic tilt phenomenon was demonstrated by Sarti et. al. (1996) with the reverse crunch over fifteen years ago. Willet et al. (2001) demonstrated the same thing five years later, also with the reverse crunch, and Duncan (2009) showed the same with a Swiss ball jacknife maneuver.

If you want more evidence, Moreside et al. (2008) showed that experienced belly dancers could completely separate upper and lower abdominal activity during belly roll movements, and that the lower abs dominated the upper abs when pelvic motion was conducted upon a relatively fixed trunk.

Finally, research by Vera-Garcia et al. (2011) concluded that, "different neuromuscular compartments appear when the objective changes from pelvis to thorax motion."

Many strength coaches scoff at the notion of attempting to target the upper or lower abdominals during training, but proper lumbar stability requires strong abdominals, particularly in the upper regions while proper pelvic stability requires strong abdominals, particularly in the lower regions. Both are needed for maximal lumbopelvic strength and stability.


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PostPosted: Wed Feb 29, 2012 10:39 am 
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Preposterous!

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PostPosted: Wed Feb 29, 2012 1:34 pm 
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The lower abdominal EMG and posterior pelvic tilt phenomenon was demonstrated by Sarti et. al. (1996) with the reverse crunch over fifteen years ago. Willet et al. (2001) demonstrated the same thing five years later, also with the reverse crunch, and Duncan (2009) showed the same with a Swiss ball jacknife maneuver.

If you want more evidence, Moreside et al. (2008) showed that experienced belly dancers could completely separate upper and lower abdominal activity during belly roll movements, and that the lower abs dominated the upper abs when pelvic motion was conducted upon a relatively fixed trunk.

Finally, research by Vera-Garcia et al. (2011) concluded that, "different neuromuscular compartments appear when the objective changes from pelvis to thorax motion."

I'd actually like to read these studies. Are any available to us?


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PostPosted: Wed Feb 29, 2012 3:46 pm 
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ask Bret on the T-Nation livespill


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PostPosted: Thu Mar 01, 2012 2:42 am 
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deja-vu. I remember having this discussion already. I know there is post not too far down, where I talk about exactly what's wrong with those studies.


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PostPosted: Thu Mar 01, 2012 5:08 am 
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well Ironman to be fair you say "I think the greater activation of the hip flexors could account for that reading. We also have no way to account for those readings being that way from a physiological perspective. So while the readings may be proven, thinking it comes from emphasizing the lower abs is simply presupposition, without some sort of mechanism for how it is possible"

which may be the case, but we don't really know the whole story. Also, would you not think that the experimenters would account for extraneous variables such as hip flexor activation when conducting the experiment?

Surely "I think" would never satisfy someone as scientific as yourself.

As for the mechanism, well he does propose the theory about different portions of the abs being responsible for different functions, trunk and pelvic stability, which would certainly make sense and definitely jives with my own experiences

***edited to clarify my position slightly


Last edited by robertscott on Thu Mar 01, 2012 10:45 am, edited 1 time in total.

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PostPosted: Thu Mar 01, 2012 5:16 am 
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I've emailed Bret to ask about how they controlled for greater hip flexor activation. Will keep y'all posted...


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PostPosted: Thu Mar 01, 2012 6:05 am 
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Showing increased "lower" ab activation WITHOUT hip flexion would probably have me convinced.

Also liked the quote/note from Charlie Weingroff via Mike Robertsons blog
http://robertsontrainingsystems.com/blo ... weingroff/

"EMG is fraudulent and stupid – handle some weight and lift."

I don't understand EMG enough to make a proper judgement on it. However, there's just something not right about it, and a few very reputable people have said it's useful but, doesn't tell us the whole story. In other words, i'm hesitant to put my house on the validity of the data.

Not to mention the usefulness of it (I believe he "disproved" spot reduction in the same section of the article, too). For example, lets say you can convince me that movement X really does activate the lower abs more than the upper abs, my response would be, "so what?".

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PostPosted: Thu Mar 01, 2012 10:47 am 
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to rock those hawt abz Kenny, why else?

(on a side note, Kenny I'm going to give you a shout over the next few days to see if we can arrange a session)


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PostPosted: Thu Mar 01, 2012 5:35 pm 
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robertscott wrote:
well Ironman to be fair you say "I think the greater activation of the hip flexors could account for that reading. We also have no way to account for those readings being that way from a physiological perspective. So while the readings may be proven, thinking it comes from emphasizing the lower abs is simply presupposition, without some sort of mechanism for how it is possible"

which may be the case, but we don't really know the whole story. Also, would you not think that the experimenters would account for extraneous variables such as hip flexor activation when conducting the experiment?

Surely "I think" would never satisfy someone as scientific as yourself.

As for the mechanism, well he does propose the theory about different portions of the abs being responsible for different functions, trunk and pelvic stability, which would certainly make sense and definitely jives with my own experiences

***edited to clarify my position slightly


You misunderstand me. I'm not making a claim that we know exactly what this reading means. On the contrary, I'm saying that we don't know. There are other explanations he hasn't discounted, and he has no mechanism for how this is supposed to work. So this can only come about through some degree of presupposition, and is therefore junk science.

Does he mean abs in total, or the rectus specifically? I would agree with the former and not with the later. Experience doesn't matter. Anatomy is what matters. How exactly can sections of abs be isolated to a degree that makes any difference?

He needs a mechanism for how his hypothesis is possible, and not just some presupposed idea he extracted from his anal cavity.

We know that doing a particular movement causes neural adaptation, and allows one to get better at that movement. This can be done with one movement, and not nescisarily translate over to a very different movement done with the same muscles. I submit this as an alternate explanation. That's just off the top of my head.


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PostPosted: Thu Mar 01, 2012 6:15 pm 
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I didn't misunderstand you, but I don't think I explained myself very well.

I think he has proposed a mechanism of what it does - with the upper abs being responsible for trunk stability and the lower abs being responsible for pelvic stability - but agree that he hasn't proven a way in which this is possible. But, I don't necessarily take that as meaning that it is impossible.

And I still don't think it's fair to say it is junk. He's looked at some evidence, and formulated a theory. As I'm sure you know (you strike me as being very well read on philosophy so I assume you're familiar with falsificationism, you probably actually know a lot more about it than I ever will!) you can never really PROVE a theory, just support it, and the links he provided certainly support his. He does present it as a fact, which may not be very responsible, but I think any academic could probably be accused of the same thing.

I don't expect I've convinced you of anything, and I know you say experience is irrelevant, but my experiences are not irrelevant to me. I've always believed the lower portion of the RA can be emphasised (not isolated) and will always believe that. Even if Contreras changes his stance, I will not change mine. The link Dub posted in the last thread we had about this, plus the studies Contreras mentioned and his own personal research support my theory.

Another example from my own life (again, I know this isn't scientific but it explains where I'm coming from): I have added in a few sets of cable crunches at the end of my leg routine to give my abs a bit more "pop". I had been doing them kneeling. and felt the lactic acid burn in the top 4 of my 6 pack. Tonight, for the sake of variety, I decided to do them standing. I felt the middle portion of my abs much more emphasised. This cements in my mind the idea that it can be done.


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PostPosted: Fri Mar 02, 2012 3:05 am 
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Quote:
but agree that he hasn't proven a way in which this is possible.


But yet that isn't the end of the discussion?

Quote:
don't necessarily take that as meaning that it is impossible.


It doesn't have to. You can't prove there are no dragons either.

Quote:
And I still don't think it's fair to say it is junk.


His conclusion is presupposed. That is a definitive trait of junk science, and at odds with the scientific method.
Quote:
He's looked at some evidence

Yea, after he decided what the conclusion was.

Quote:
you can never really PROVE a theory, just support it

Irrelevant. That has no bearing on this being junk science.

Quote:
He does present it as a fact

That's not something that is wrong with it.
Quote:
I know you say experience is irrelevant

Not in every context.
Quote:
my experiences are not irrelevant to me

That is obviously an exception. Explore this idea further by watching the move "Contact".

Quote:
I've always believed the lower portion of the RA can be emphasised

That's the problem. You believe something without reason, and while disregarding the relevant physiology that makes such belief quite irrational. This has left you open to confirmation bias. This means you are biased to accept this study without scrutiny. This is an example of what is wrong with this sort of belief. A little speculation about possibilities is one thing, but actual belief is problematic.

Quote:
Even if Contreras changes his stance, I will not change mine.

That's even worse. The belief is so hard set, no empirical evidence or logical argument will convince you otherwise. The human propensity for this behavior is the root of most things wrong with this world, and the reason virtually all such things are nearly impossible to change. You do it with abs, which is virtually meaningless in the grand scheme of things, but others do it with much more important ideas.

Quote:
plus the studies Contreras mentioned and his own personal research support my theory

No, it just triggers the confirmation bias phenomenon.

Quote:
Another example from my own life (again, I know this isn't scientific but it explains where I'm coming from): I have added in a few sets of cable crunches at the end of my leg routine to give my abs a bit more "pop". I had been doing them kneeling. and felt the lactic acid burn in the top 4 of my 6 pack. Tonight, for the sake of variety, I decided to do them standing. I felt the middle portion of my abs much more emphasised. This cements in my mind the idea that it can be done.


The rectus is not the only muscle involved here, which is the problem with that. Such an experience is a perfectly valid way to come up with a hypothesis. However looking into anatomy should show you it is highly unlikely. There is also the issue that the area of your brain that receives these pain signals usually isn't sophisticated enough to know exactly where it comes from. Abdominal pain is notorious for this.


Furthermore the tests can more readily be explained by which neural connection carried most of the signal that made it contract. You'd have a better case for working the left and right sides independently, but even that doesn't work. One reason for that, is the same nerves feed the obliques, and any unilateral movement activates that rather than isolating one side of the rectus; but at least the fibers aren't joined, although they are connected by other tissue.


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PostPosted: Fri Mar 02, 2012 3:32 am 
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I'm amazed that guys like Contreras can really be competent with EMG. Not that he isn't, but it's surprising to me if he is. Neurolotists and Rehab docs spend a long time learning to do it, and they start with a pretty deep knowledge of neuroanatomy and musculoskeletal anatomy. I don't know where he learned to do it. Did he just buy the machine and start hooking it to himself? I'm not sure I'd put a lot of weight in his EMG work. Not sure that surface EMG is the technique that can really produce the data that one would need to reach good conclusions about these things.

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PostPosted: Fri Mar 02, 2012 5:17 am 
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Ironman wrote:
Quote:
but agree that he hasn't proven a way in which this is possible.


But yet that isn't the end of the discussion?

Quote:
don't necessarily take that as meaning that it is impossible.


It doesn't have to. You can't prove there are no dragons either.

Quote:
And I still don't think it's fair to say it is junk.


I think that's spurious. There is no scientific evidence to prove foam rolling works, but I have seen it time and again with my own eyes. Just because there's no scientific explanation for something, doesn't mean I won't believe it if I observe it.

Ironman wrote:
His conclusion is presupposed. That is a definitive trait of junk science, and at odds with the scientific method.


he drew his conclusions from his own experiences, and then the EMG tests supported his theory. Perhaps that is junk, but it works for me. The only thing I can see wrong with that is that EMG might be suspect...

Ironman wrote:
Quote:
you can never really PROVE a theory, just support it

Irrelevant. That has no bearing on this being junk science.


I disagree, his results and the results of others support his theory. Seems relevant to me.

Ironman wrote:
Quote:
I know you say experience is irrelevant

Not in every context.


Oh really? I'd be interested to hear an explanation of this if it doesn't take us too off topic

Ironman wrote:
Quote:
my experiences are not irrelevant to me

That is obviously an exception. Explore this idea further by watching the move "Contact".


cool, I will, thanks for that. What a minute, that's not that rank film where Jodie Foster contacts aliens is it? If it is, I've seen it, and I don't much care for it...

Ironman wrote:
Quote:
I've always believed the lower portion of the RA can be emphasised

That's the problem. You believe something without reason, and while disregarding the relevant physiology that makes such belief quite irrational. This has left you open to confirmation bias. This means you are biased to accept this study without scrutiny. This is an example of what is wrong with this sort of belief. A little speculation about possibilities is one thing, but actual belief is problematic.


I disagree that it is without reason. I believe it because I have observed it. Had I never observed it, I would not believe it.

Ironman wrote:
Quote:
Even if Contreras changes his stance, I will not change mine.

That's even worse. The belief is so hard set, no empirical evidence or logical argument will convince you otherwise. The human propensity for this behavior is the root of most things wrong with this world, and the reason virtually all such things are nearly impossible to change. You do it with abs, which is virtually meaningless in the grand scheme of things, but others do it with much more important ideas.


again, it's not that I have this belief based on some thousand year old scroll discovered in the lost city of Atlantis or something. I've seen it with my own two eyes, and felt it in my own six pack.

I do actually consider myself quite a skeptical individual, but I can tell from where I feel lactic acid, DOMS and fatigue in my abs what exercises have emphasised each bit.

Ironman wrote:
Quote:
plus the studies Contreras mentioned and his own personal research support my theory

No, it just triggers the confirmation bias phenomenon.


I must've been asleep in class the day they taught us about the confirmation bias phenomenon. Doesn't change the fact that the studies presented support my view though...

Ironman wrote:
Quote:
Another example from my own life (again, I know this isn't scientific but it explains where I'm coming from): I have added in a few sets of cable crunches at the end of my leg routine to give my abs a bit more "pop". I had been doing them kneeling. and felt the lactic acid burn in the top 4 of my 6 pack. Tonight, for the sake of variety, I decided to do them standing. I felt the middle portion of my abs much more emphasised. This cements in my mind the idea that it can be done.


The rectus is not the only muscle involved here, which is the problem with that. Such an experience is a perfectly valid way to come up with a hypothesis. However looking into anatomy should show you it is highly unlikely. There is also the issue that the area of your brain that receives these pain signals usually isn't sophisticated enough to know exactly where it comes from. Abdominal pain is notorious for this.


Oi! Who's brain you calling unsophisticated???

heh, well at least we can agree my experiments on myself were reasonable. My knowledge of nerve connections and things isn't great so I can't really give an explanation here. Perhaps different exercises not only emphasise different portions of the RA, but also change the degree of involvement of the other ab musculature. I'm just brainstorming here...

interesting discussion this.


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PostPosted: Fri Mar 02, 2012 7:02 am 
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robertscott wrote:
I think that's spurious. There is no scientific evidence to prove foam rolling works, but I have seen it time and again with my own eyes. Just because there's no scientific explanation for something, doesn't mean I won't believe it if I observe it.


Foam rolling was mentioned so I had to jump in.

Foam rolling kinda sorta has a mechanism - it's quite vast and complicated subject, seems to be still in its infancy in terms of our understanding, and is definitely currently beyond me. However to say there is no research is definitely misguided. I've still not had the time to get my head around the research that's out there already. There's been loads of research done on "manual therapy" and the various techniques that this entails, although even that is still in its infancy. Foam rolling pretty much tries to do a similar job to a manual therapist. People probably do a search on pub med for "foam rolling", don't find anything, and say, "there's no research". It's kind of like saying there's no research to prove a gun has ever killed someone (bullets kill people).

I don't fully understand it, to be honest (I also don't understand how an engine works but, I still drive my car). I just kind of roll my eyes when I hear the "no research" point. One person I use as a resource for this stuff is Patrick Ward - http://optimumsportsperformance.com

Also,

robertscott wrote:
I do actually consider myself quite a skeptical individual, but I can tell from where I feel lactic acid, DOMS and fatigue in my abs what exercises have emphasised each bit.


To me this part of the issue. When was the last time you felt all these things when doing chin ups? According to the same source (Bret), they work your abs better than the exercises you mentioned. If lactic acid, DOMS, and apparent fatigue were good indicators of how hard they were working, then the chin up point would be wrong. Therefore, you need to question the relevance of these things especially when trying to determine the effectiveness of an exercise. I'm sure he cited Turkish Get ups, too, as one of the best ab exercises. Whilst you'll definitely feel DOMS the first few times doing them, it's very unlikely you'll actually "feel" your abs doing anything in the process.

In other words, by this logic, chin ups, get ups, squats, dl's, OH press, etc, don't work the abs.

I agree, interesting discussion :study:

KPj

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