Thou shalt not show armpit hair, ever.
Your level of douchiness is exponentially related to the amount of armpit hair showing
Wife beaters at the gym (cringe!) -- it's best to save the cut-outs for art class.
There she blows. Snotting in the shower is a big, NO pas!
People who blow their noses in the steam room, clip their nails or shave in the sauna.
Big ick factor here. Never bring your personal grooming rituals into the public bathhouse.
The gym is not a karaoke bar.
People who sing to their iPod music at the top of their lungs, so the who gym has to hear how they have the vocal rang of a dying cat. Can't sing? Lip sync. I hear all of the "musical artists" are doing it these days.
Smelling like a cab driver is never an option.
People who don't wear deodorant while working out, should be banned from the gym. Period. Know anyone who wants to inhale eau de B.O. with every breath you take?
And along those same lines...
He who passes gas, should get his a## out of the gym.
People who fart when running on a treadmill - repeatedly, during workout rush hour, are the worst. Girl with your headphones in, tooting with every step you take-- yeah, you. While you may be singing "the sound of silence" at the top of your lungs... We can still heeeaar you! Gyms created a special room just for you, and it includes a private stall.
Mirror, mirror on the wall. Never take a gym selfie, never..nope, not at all.
Dude, it's just plain creepy.