Oprah's time is close to the average finishing time for marathons in 2011, which was 4:37. The average marathon finishing time for men in U.S. marathons was 4:26 and the average finishing time for women was 4:52, according to MarathonGuide.com.
If you're training for a marathon and wondering what your estimated time may be (and if it will be faster than Oprah's), here's how you can predict your marathon time.
If you're still training and you're hoping to improve your time, here are some tips for how to run a faster marathon.
Also see: Celebrity Marathon Times
Celebrity Half Marathon Times
What's a Good Time for a Marathon?