Why is the rectus abdominus muscle seperated into 6 segments?

Blacktie.

Don't know if this is posted in the right place but I was just wondering why the abs are seperated into 6 segments rather than being one large flat muscle (I know its one muscle but why the 6 parts!?). Is there a benefit in flexibility or what is it? Also what is it that seperates them cartilage or ligaments or something else?

Thanks in advance. I know strange questions but I'm a strange person :-).

LegacyUser

Blacktie. wrote: »

Don't know if this is posted in the right place but I was just wondering why the abs are seperated into 6 segments rather than being one large flat muscle (I know its one muscle but why the 6 parts!?). Is there a benefit in flexibility or what is it? Also what is it that seperates them cartilage or ligaments or something else?

Thanks in advance. I know strange questions but I'm a strange person :-).

6 Segments?

http://upload.wikimedia.org/wikipedia/commons/9/95/Rectus_abdominis.png

Blacktie.

Wasn't aware of the 2 at the top but arn't the bottom two known as the abdominus transversalis?

LegacyUser

Blacktie. wrote: »

Wasn't aware of the 2 at the top but arn't the bottom two known as the abdominus transversalis?

Still the abs!

Blacktie.

Yeah fair enough but why the seperation?

Gillo

At a guess, I'd say the six different section's work in conjuction each other to aid movement as opposed to one singular large muscle.

My second guess is, I'd look stupid with a one pack:D

BJohnson

The fibrous bands that run horizontally through the rectus abdominis help transmit the hoop forces generated by transverse abdominis and the internal and external obliques. Without these bands, the force generated by those muscles would tear rectus abdominis apart.

CHD

Real question is Why not?

Superdub2

Since we are on this topic i have a question..........

........ Why is the sky blue??

jayoo

light going through nitrogen particles or was that fishfingers?

RacoonQueen

The rectus abdominus is actually split into ten.

Supercell

BJohnson wrote: »

The fibrous bands that run horizontally through the rectus abdominis help transmit the hoop forces generated by transverse abdominis and the internal and external obliques. Without these bands, the force generated by those muscles would tear rectus abdominis apart.

Dr Supercell says a big brush paints over small details.

BJohnson

Supercell wrote: »

Dr Supercell says a big brush paints over small details.

Sorry, maybe I can be more clear. It's an interesting question.

Rectus abdominis has fibres that run up and down. The obliques and transverse abdominis have fibres that run horizontally, generating force in a circle around the abdomen. Where these muscles attach into rectus abdominis, they pull outwards on the muscle. Having fibrous bands that run through rectus abdominis in the same direction as the muscular forces being produced by the obliques and transverse abdominis allow rectus abdominis to withstand more pressure from the surrounding muscles. If those fibrous bands were absent, a strong contraction by the obliques and transverse abdominis could pull rectus abdominis outwards with enough force to rip it apart.

As with a lot of things in anatomy, it's not a question of "why" is it like that, since animals didn't make a decision to develop in any particular way. The question is more one of what advantage could that structure provide in an evolutionary sense.

Does that make more sense?

Blacktie.

Yeah thats great pretty much answers my question thanks alot :-)

BrokenArrows

Superdub2 wrote: »

Since we are on this topic i have a question..........

........ Why is the sky blue??

Simple answer. Light shines through nitrogen particles as said before.

complicated answer
http://www.sciencemadesimple.com/sky_blue.html

cowzerp

Muscles tend to suit the bones that are moved by them, in this case think spine!
the spine moves at every vertabrae so needs a different muscle type than say the tricep for extending your arm! 1 long normal muscle would just make you move funny! crap explanation but i hope you get it..

BossArky

God made the world in a week, an ab per day for 6 and took Sunday off. If he hadn't been so lazy we'd all have 7 packs :rolleyes:

Superdub2

BrokenArrows wrote: »

Simple answer. Light shines through nitrogen particles as said before.

complicated answer
http://www.sciencemadesimple.com/sky_blue.html

So its not because of the reflection off the worlds oceans?? oh no thats why the oceans are blue!