Probably not. Mammals and birds demand 10~100 times more oxygen to survive than other vertebrates (source), as our metabolism is rather high; I don’t think that the oxygen in water is able to supply that. And a change in that metabolic rate seems a bit too involved to be feasible, specially given that our brains use a lot of energy (thus oxygen).
With selective breeding you could technically be lucky and slow down the metabolism, selective breeding isn’t a very precise way to change something, but the actual problem would be time anyway.
The problem is that any change slowing down the metabolism would be deleterious in nature: no/slower body heating, lower brain capabilities, slower healing, increased reaction times, etc.
As a rough comparison, it’s like trying to reduce the energy demand of a computer. There’s some room for optimisation but eventually the only way to do it is by reducing the amount of things that it does, by throttling its components.
