Georgia Tech for many years required male students pass a Drownproofing class. The technique was developed as something that could quickly and easily trained to soldiers and sailors.
https://en.wikipedia.org/wiki/Drownproofing
https://www.isye.gatech.edu/news/surviving-drownproofing-101
Lean black athletes tended to have a hard time with the course, as they didn’t have much in the way of natural buoyancy. The young ladies who took the class (they were not required to take the course), on the other hand, generally found it pretty easy due to their physiology tending to have plenty of natural buoyancy. Vive la différence!
“You’re the most brilliant Engineering student we’ve had in many years and we were really looking forward to working with you on your interesting and original research project. However you can’t swim.”