I will leave work to go to the gym 3-4 times a week. might take 50 minutes that I'm gone total. I count it as my lunch hour and then eat at my desk while working. I've also had days where I'll leave 15 minutes early to get to the gym before rush hour. never had an issue.
I oversee a department and I don't have issues with my employees coming in a little late or leaving early once in a while. if their work is getting done, getting done on time, and getting done correctly, I have no issues. my employees love me and not surprisingly, they work hard when here and make sure what they do is done correctly.
no naps at work however. we do have one employee in another dept who I've heard will sometimes fall asleep at his desk. He's an older gent who the company is just waiting to retire.