That's dangerous, you're too old to be doing it!

Boxing. Up until a few years ago we still had an old-school gym nearby, and had sparring a couple nights a week. Kinda miss it now that it's gone, but I still have a speed bag in the basement.
"I don't wanna hurt you, old timer..."
"Need a hand getting up off the canvas, kiddo?"

One of my best friends father walked to work at least a mile and back every day. Had to be around 60+. One night a big guy broke into their house looking for drugs or money for drugs. David's skinny father told him to get out, but the guy rushed him. He came to with the cops waiting for him to go to jail. Turns out David's father was a golden gloves boxer in the Navy.