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Repeated freediving – An efficient and safe method to rescue subjects trapped in cars underwater
(www.sciencedirect.com)
That reminds me of when I was in an underwater hockey league. When we started, I was one of the stars because I could stay down for a minute or so, working pretty hard. But once we got proper coaches, I was quickly turned into a bystander because I didn't have the team awareness to be remotely effective in what I called the "bob and breathe" technique of keeping a constant rotation in a passing game.
Anything about Freediving.