Trainer

The trainer is a buff fish who owns the Gym in the episode "The Krabby Kronicle."

Description
The trainer is a golden brown, muscular fish with yellow lips and a gold and yellow striped dorsal fin. He wears a light blue speedo. In "MuscleBob BuffPants," he is olive green with an orange speedo.

"MuscleBob BuffPants"
He is seen at Mussel Beach when waltzes up in his Anchor Arms.

"The Krabby Kronicle"
He previously had Larry the Lobster as a member of his gym. He is a reader of the Krabby Kronicle and believes Larry is a wimp after a fake headline that he was beaten up by a weaker fish.

He is first seen kicking Larry out of his gym due to the latter embarrassing his reputation, which upsets Larry. In actuality, Larry let the fish punch him and he had no problem with the punch, but due to the timing of the photo and the false headline, it ends up looking like he was actually feeling pain and getting beaten up.

He doesn't let Larry explain what really happened and bans him from the gym permanently.