My aunt was a competitive swimmer in her youth. Hasn’t swum for years but physio told her it would be good for her, so off she trotted to the local over 60’s session (she was in her 70’s).
Got properly shouted at by a man for swimming “too fast”. She was keeping well out of everyone’s way, plenty of room etc, only doing slow crawl and breastroke, hardly hacking it like Phelps, but he took great offence at a woman swimming faster than him.
He complained to the lifeguard that “aggressive swimming” shouldn’t be allowed. To their credit they told my aunt not to worry, and ignore him, please come back next time and they’d sort it.
They’d roped off a lane especially for her 