During the past few weeks, there’s been a lot of hype in the media about the “dad bod.” It’s basically the idea that women are cool with men letting themselves go once they’re married with kids.

Well, a new study just threw that out the window.

Researchers at Yale University just found that the key to a good marriage is: A man who doesn’t let himself go.

They found that married women are much less likely to be depressed if their husband regularly works out — even if they never work out themselves. Men who exercised also were happier than men who didn’t.

For whatever reason, when women worked out, it didn’t have any effect on the happiness of a marriage.

The researchers’ theory here is that exercise has a stronger positive psychological effect on men than women. Since it makes men feel so good, that happiness rubs off on their wives.