I wouldnt expect to see any excess bodymass on him, competing at that level.
Perhaps he's just a naturally skinny guy ....unless you have seen pics of him looking considerably bigger in the past.
LOL, the press have a magical abiity to find the most unappealing pics of people. Saw a photo of Victoria Beckham in the Sun today, her leg looked a right mess...but i'd sooner feel her than feel hungry
(just making a point BTW..i dont fancy her...but one bad pic doesnt tell the whole story)