Dave Palumbo said it's not the drug access in Kuwait. It's because they have 24/7 access to food, sleep, and great gym equipment! 
I'd love to know what they're doing different. How come someone doesn't know by now?
I'd like to hazard a guess here based on my own experiences - medical support. And by that I mean having the support and non-judgemental attention of
a real doctor who isn't judging you and is taking your bloods on a weekly/monthly basis
knowing full well what compounds you are using..
Removes the guesswork and lets you blast to the limit...
Try that in the UK in the '90s.... Jeez...
Edit: and I'm betting those 'medical records' don't get transferred back to the US/UK and so don't prejudice and medical insurance, etc....