There is a guy at my work place who's 5'11 and has never been under 240 lbs since high school. He played football in HS and college, is in his late 20s now, and still goes to the gym and plays basketball regularly. He also ran track in HS and got sub 12, though he doesn't remember whether it was hand timed or electronic.
He claims to have run a sub 5 mile last year during practice, but there is no video of him doing it. He refuses to try again since he puked all over and had headaches afterwards, so he has no desire to go through that again (even when I offered him a few hundred bucks if he succeeded at his current weight). He says he sprints and does intervals on a regular basis but does not do continuous distance runs.
He did show me a video of him running a hand timed 56.5 400 and a 2:13 800. So how plausible is his sub 5 claim given those PRs? Did he even break 5:10?