Olympian Carrie Tollefson's Core Workout

Watch a video of Olympic runner Carrie Tollefson's core workout.

Carrie Anne Tollefson is an American middle distance runner who was on the U.S. 2004 Summer Olympic team. She says, "Every runner knows a strong core is the key to a speedy run—but we don't always feel like hitting the mat to work on that six-pack.

"When I was training for the Olympics, I did core work about five days a week. I had to! For me, core was huge so I could race fast. I needed a strong core to hold my form over the long, hard 5K as well as for both strength and speed in my 1,500 meters or mile.

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"Being able to drive my knees up and turn my legs over while keeping my hips underneath me was one of the reasons why I was a successful athlete. It's no surprise that I worked hard on the track and roads, but not everyone realizes how much time elite athletes spend in the weight room—or on a yoga mat at home.

"I used to perform an 8-minute routine about three times a week. I still do it, but I've had to incorporate more pelvic wall strength exercises since having children. Still, I like to switch it up. Maybe I'll add a medicine ball or partner workout, but I would have to say that Crunches and Back Extensions always seem to find their way into my day.

The video above shows a few of the exercises that helped me keep my form."

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