I used to head to the local pool before work to do a few laps. There was a dude in his fifties who would do about 150 laps (4km /2.5mi) drinking regularly from a masterfoods tomato sauce bottle

https://www.masterfoods.com.au/cdn-cgi/image/width=277,height=277,f=auto,quality=90/sites/g/files/fnmzdf1746/files/migrate-product-files/m2qzgte5yyivo7dy9opi.png

(it was filled with water)