Your metabolic rate can be several times higher in a pool or other body of water than it is on land without any exercise at all. Body heat is lost at a much higher rate when you are submerged in water and your body will burn more fuel to maintain core temperature.
You say she “has to create” this and that he “apparently needs parenting”. Did you have some additional context that informs that opinion?
Couldn’t there be other reasons, such as she just doesn’t like doing those particular chores?