HGH causes that, bigtime, organ growth --> distended stomach. Check out TheUsual's hideous avatar.
TheUsual's avatar is a fake. It's a doctored image. It has appeared before on other boards and been debunked.
As for organ growth, honestly if it were to such a serious degree with HGH, then how come Jay Cutler doesn't have the gut? He uses it. Why didn't Andreas Munzer? He used a metric crapton of it. Or Lee Priest? He has stated in interviews that he has used it the last few years.
There ARE several things known to cause a distended abdomen though and they are more mundane than you'd think. Any compound movement that requires strong core muscles for stability can cause abdominal distension if performed with a purposeful distension of the abdomen for the added stability it afford. Heavy squats and heavy deadlifts come to mind. While these don't have to be performed while distending your abs, doing so gives you much greater stability during the lift and can allow for much heavier weights used. If one doesn't counter that with the appropriate practice of stomach vacuums in their routine, it will cause stomach distension to a great degree.
Another major cause is actually food intake and constipation. Taking in large quantities of food in one sitting can and WILL increase stomach size as well as intestinal size. Constipation can also increase intestinal size greatly due to a higher volume of stool remaining within the bowels for an extended period of time. This is more common than you think though not so evident to most people visually because the vast majority of those afflicted to that degree are obese.
In any case, if you take a good look at Ronnie's training routine and his diet, it seems to me, he has at least two of those and possibly all 3. He performs squats, deadlifts, and leg press all while pressing his stomach out as far as it will go. He also eats an ungodly massive amount of food every day and his individual meals are huge. Not sure about the constipation, but with the protein he's taking in, he'd have to take in a very serious amount of fiber, a whole lotta water, and a ton of EFAs to keep that colon regular. Around contest time, most pros, and Ronnie is no exception, get very dehydrated. Dehydration most definitely causes constipation as can androgen usage as well as the use of AIs. Seems to me, those 3 are the more likely culprits of his gut.
