A Northern Fur Seal stretches his mouth on the trainer's command at the New England Aquarium in Boston on Friday, June 26, 2009. A new program titled 'Move It!' featured in a new exhibit at the aquarium, aims to entice an increasingly obese generation of kids to get moving. (AP Photo/Eric J. Shelton)AP - Yes, he's obsessed with grooming, and he occasionally barks at you, but in most ways Isaac is not your typical fitness instructor. He weighs in at 350, eats 16 pounds of food at a time and he's only 9 years old. And he's a seal.