gainer hater
A person who talks trash about the gym and everyone who's in it. They think they're king of the castle.
The gainer hater posted on Twitter: 'Gainers are just people who can't handle a little protein.'
I saw the gainer hater at the gym. He said, 'I'm too good for this place.'
My friend is a gainer hater. He said he'd rather sit on the couch than lift a barbell.