Alanis Morissette, Mark Bittman, Dan Jansen, Edward Norton and Anthony Edwards. What do these people have in common besides their celebrity status? They’re all running in this Sunday’s 40th Annual New York City Marathon. Considered to be one of the world’s premier races, this year’s registrants total more than 42,000 people and will cover, as all marathons do, 26.2 miles. Sitting back in awe of these numbers, here at wOw the conversation turned to what kind of person chooses to put him- or herself through such a challenge. When we looked for answers, here’s what we found: Ten heavy hitters from Sarah Palin to Will Ferrell to Oprah Winfrey. Click through the slide show for more.

Are you planning to run a marathon? Read What You Need to Know Before You Run a Marathon, by Dr. Holly Andersen.