13. Taking selfies of every move
It’s a good way to get a lot of pictures, but not a great workout.
14. Taking advice from anyone who’s not a certified trainer
Everyone who has a body has an opinion on exercise. That doesn’t mean they actually know anything.
15. Choosing the locker next to the person who's a little too comfortable with nudity
Maybe you didn’t know you chose the locker next to this person when you walked in, but if I were you, I’d switch asap. Chances are this person is perfectly comfortable carrying on long conversations sans pants -- it’s a free country and all, but it’s possible to be a little too zealous in exercising that freedom.