This Sunday, I’ll be running in my first half marathon in two years,  and I know I will be well-prepared. When people train for a race, sometimes they focus solely on their running schedule and making their weekly mileage quota. Big mistake. Core strength is important to keep a runner upright and in proper form, especially during long runs. A strong core can also prevent common runner’s injuries. Below are my top three core exercises for runners. The exercises listed will strengthen the abdominals and the muscles of the back and hips, and are very effective for anyone looking to tone up their midsection.

Plank

What it works: Strengthens and stabilizes abdominals, back and shoulders

Start by laying face down on a mat. Press yourself up into a push-up position, resting on your forearms. Make sure your elbows are directly under your shoulders. As you hold this position, tilt your pelvis forward, and squeeze your heels and quads together. Keep your gaze just beyond your fingertips. Your back should be flat, making a straight line from your head to your heels.

Russian Twist

What it works: Obliques

The obliques are the muscles responsible for rotation of the torso. Runners who fail to strengthen the obliques will make the abdominals and back muscles do all the work to support the body. Sit on a mat with your knees bent, as if you were at the top position of a sit up. Angle your body so that your upper body is at a 45 degree angle with the ground.  Hold your arms straight out in front of you and hold your hands together. Or, with bent arms, hold on to a weighted ball or dumbbell. Twisting through the torso, move your shoulders from side to side. Make sure you are not just swinging your arms, but that the move originates from the waist. Keep twisting from side to side without stopping for at least 16 rotations. The slower and more precise the movement, the better. If you experience lower back pain, substitute with bicycle crunches.

Hip Raise and Hamstring Curls on the Swiss Ball

What it works: Everything! I love this exercise because it works the glutes, hamstrings, calves, abdominals and lower back muscles.

Runners need strong posterior chain muscles. Simply put, it’s the muscles behind us that are propelling us forward. Start by laying face down on a mat with your feet propped up on a Swiss ball. Place your hands next to you on the mat for support. Using your glutes, lift your hips off the mat and hold this position for a few seconds as your stabilize yourself. Brace your core to help from shifting around. Using your hamstrings, pull your heels in toward your butt, raising your hips higher as you go. The bottoms of your feet should be flat on the ball at the top of the motion. Pause for a second, then lower down with control. If this is too difficult, just start with the hip raise, omitting the hamstring curl.