The first time I heard that was from a Baz Luhrmann's the Sunscreen Speech song. It's also mimicked the advice I've read here.

So today, as I was walking home from the gym, I took my shirt off. In public. For the first time in at least 6 years. I didn't care what anyone thought about my pecs, my lack of muscle definition, or my massive crooked nipples. I walked all the way home from the gym covered in a sheen of sweat and not a single fuck was given.

So what did you do today seddit?