The potential for abuseis quite real and yes, a four-room
  changing scenario is more logical. Still, I don't think there
  should be a need for gendered changing rooms anyhow; but our
  cultures have built up a very strong secrecy about the body; the
  prize dangled (pun intended) as reward for marriage. But will
  Planet Fitness change society's attitudes towards the human
  body? *Hard to say. *Maybe a 3rd changing room for "Other" would
  suffice. You have to remember: keeping locker rooms
  gender-separated DOESN'T eliminate abuse. *Gay men and Lesbian
  women have used locker rooms as pickup places as long as there
  have been locker rooms, so no matter what you do, you have to be
  on your guard a little. Thankfully, I never cared who I was
  changing in the room with. *I've been in mixed-gender changing
  rooms, same gender, all the same. *We all look weird naked. *I
  find the human body hysterically funny.