You can't just declare yourself an athlete, can you? Some fat lad working in Tesco can't just go, 'Oh by the way I'm an athlete, I need to eat this goat curry and drink this here well water.' Everyone's going to know he's talking jive and chop his arms off, or whetever the punishment for eating in daylight it.
It's like you going to the butcher in Lent and trying to buy meat. claiming to be a Protestant. He's going to defenestrate you quicksmart.