I hate to break it to all the hardasses in the thread, but plenty of people in 'important' positions nap at work all the time. When you work a 24/7 job that requires 100% of your time and effort you have to plan in sleep. That means what when you are up at 4am for the conference call in Italy you are likely going to schedule in some nap time at your desk that afternoon so that you don't suck at your job the rest of the day.
The people who think that spending more time at work and neglecting their physical needs is just something that the most dedicated workers do, are the ones who end up falling asleep all the time and fucking things up.
As an example, I worked for a VP at my last company who would fall asleep in almost every meeting he attended. The guy would show up for work at like 6am, and be there till 6pm every day. He was the guy scheduling meetings at 4pm on Friday just because he wanted to make sure you were working the whole week. He's the guy who would schedule so many meetings throughout the day that he would end up having to schedule them in over lunch too. So as a result he ate out of the vending machines for breakfast and lunch every day and then slept through every meeting. He was in terrible physical shape, getting fatter by the day, he was sick ALL the time and he missed all the info being discussed in the meetings and was never current on what was going on...the guy was awful...but hey he was there at 6am giving everyone else shit for not coming in earlier, not being as dedicated to the company as he was.
My dad is a director with a fortune 100 company, my wife is a senior manager with a fortune 100 company. It isn't unusual to find a quiet spot and take a short nap to refresh yourself on a long day, it improves productivity.
Work life balance isn't just a stupid HR class you have to listen to once a year. You know what your body needs, listen to it. If you need more sleep then get it. If you have employees who are productive but they take a reasonable nap during the day then let them, if it works for them then who cares.