"Fat means you are getting enough to eat and are not malnourished".
I'm extremely well-nourished and energetic, can practice martial arts, which put enormous strain on the body because, unlike other sports, it's taking impact and even punching/kicking someone else without getting hit is still taking milder impact on your limbs according to Newtonian mechanics, for hours on end, and can study for days on end without tiring. My body can still function at near-maximum capacity after 5-6 hours of continuous physical effort/exercise (fighting, mind you, not walking in the park), and my mind can function at near-maximum capacity after about 50 hours awake, and last over 72 before starting to significantly slip. My only abnormal requirements for keeping up said abnormal effort easily is eating more meat/eggs and drinking more fluid than I usually would.
I am not fat. Find an argument, hypocrite. And know that you're arguing with somebody who is training to do biology-related work for a living.