oo nice how does it work?

Basically, a singular large squeezing pattern performs the function of both breathing and blood circulation. This means whenever azdoves hold their breathe, they also hold their circulation. This also means both their beath and blood circulation can become manual if you make them think of it. Luckily azdov cells tend to be more forgiving than human cells when it comes to waiting on oxygen.

The inside of the biocore has chambers for blood, pockets for air, and various structures the blood gets pumped through to perform gas exchange... err maybe "pushed" or "forced" is a better word than pumped.

cool! and dang breath holding wil be badd

They can still do it.
Just very briefly.

and are they so wide cause they have more guts?

Uh- well... the size of all their guts can vary from individual to individual,
but the males at least tend to be wide.