He called himself a "swimmer"!

"I cannot walk even one more step," he said from the back seat.
"Go get your homework," I said.
"But I cannot walk. At all. We had to do the mile run in PE, and I cannot walk anymore."
"Go to your locker. Get your homework. We are holding up car line, and people are going to get mad at us again."
"And the PE teacher says I have to do the mile again on Monday. He said he's never had anyone go more more 13 minutes before."
"13 minutes?"
"Yeah, but I was under 13. My time was 12:58, and he STILL says I have to do it again."
"Did you walk?"
"Well, duh. I told him I'm a swimmer, not a runner."
"Oh, well! Let's just go swim a mile, and then I'll tell him you're good to go."
"How about we don't, but tell him we did?"
"How about you just go get your homework out of your locker?"
"OK. But my legs are literally going to fall off."
"Well, then you probably won't have to run that mile again."
"I'll go get my stuff."

Once upon a time, he was a swimmer.