Shalane's Shredded Abs Routine

When most of us look in the mirror we want to see a nice six-pack staring back at us. Unfortunately, toned-looking abs don't always mean you have a strong core. As an athlete, I strive for a strong core because it's my power house and in general it improves my athletic performances. When other body parts start to fatigue, my core stabilizes my spine and pelvis, which keeps me powering to the finish line. But, let's be honest, I also want to look good when I slip on my uniform, just like you want to look good in your bathing suit. So here are some of my core exercises that help me achieve both my goals.
The best core exercises may surprise you because they aren't your traditional crunches and sit-ups.
Here is the core routine that I believe is the most effective — and the one I do myself:

PLANKS:  Start in a plank position, forearms and toes on the floor while keeping your body nice and rigid (make sure your butt isn't sagging or up too high). I usually hold this position for 1 minute, but you can start with less. To make it even more challenging you can do the plank on a balance ball. The balance ball makes you engage more muscles because it is unstable. This strengthens your transversus abdominis muscles and low back.

SIDE PLANKS: Lie on your right or left side, support your body with your forearm, and push up using your arm so that your hips are off the ground. Your body weight should be supported by your arm and foot. Hold for a minute on each side and focus on not letting your hips sag. This strengthens the obliques, low back, and glutes.

HIP LIFT: Lying on your back with arms at your side, palms face down, raise your legs so they go straight up toward the ceiling. Lift your hips off the floor as if your legs were trying to reach for a spot on the ceiling, then slowly lower your hips and butt back down to the floor. This exercise strengthens the rectus abdominis and obliques.

RUSSIAN TWIST WITH MEDICINE BALL: Sit with your legs bent and feet together on the ground, then lift your feet off the ground while holding the ball and shins parallel to the ground, and twist your torso from right to left with the ball, tapping the ball on the floor each time. Repeat for 30 seconds to a minute. This strengthens your hip flexors and obliques.

You can also watch a core routine that Shalane and fellow elite marathoner Kara Goucher do in their training.

What's your favorite move for a stronger core?

—Shalane Flanagan, Record-breaking marathoner