How a Strong Core Enhances Running Performance
A strong core not only reduces injury risk, but also enhances running performance. In fact, better performance may be the primary benefit of having a strong core. A 2009 study by researchers at Barry University found that six weeks of core strength training significantly improved 5K race performance in a group of 28 runners.
How does a strong core enhance running performance? This question has not been definitively answered, but I suspect that strong abs allow for a more efficient transfer of forces between the upper body and the legs during running. Although the legs get all the credit, the upper body makes a crucial contribution to power generation when you run. To appreciate this, try running with your arms pinned against your sides and feel how much harder it is. A strong core creates a tighter link between the upper body and the legs so that less force generated at one end of the body is dissipated as it travels to the other end.
You can improve the capacity of your abdominal muscles to transfer forces more efficiently by including exercises that test this capacity under load. One such exercise is the standing cable high-low pull.
Core Exercise #2: Standing Cable High-Low Pull
Stand with your left side facing a cable pulley station with a D-handle attached at shoulder height. Bend your knees slightly and place your feet slightly more than shoulder-width apart. Use both hands to grab the handle. Your arms should be almost fully extended with your trunk twisted to the left.
Now pull the handle from this position across your body and toward the floor, stopping when your hands are outside your right ankle. This is a compound movement that involves twisting your torso to the right, shifting your weight from your left foot to your right foot, bending toward the floor, and using your shoulders to pull the handle across your body. Concentrate on initiating the movement with your trunk muscles. At the bottom of the movement, pause briefly, then return smoothly to the starting position. Complete 10 repetitions. Reverse your position and repeat the exercise.
How a Strong Core Helps You Move More Effectively
Although running is a straight-ahead action, a certain amount of rotational movement of the body helps you move forward more effectively. In particular, your pelvis needs to rotate to the side as your stride opens up to allow your push-off leg to extend farther behind you. But while this happens, you want your torso to stay locked in a forward-facing position, which requires that your spine avoid rotating with your pelvis. If your spine does rotate with your pelvis, you will waste energy in much the same way you'll waste energy if you pull with one oar at a time instead of with both oars together in a rowboat.
Runners with a weak core tend to exhibit wasteful trunk rotation. You can eliminate this problem by consistently doing core exercises, such as the standing trunk rotation, that challenge the abdominal muscles. Strong abdominal muscles resist rotational forces.
Standing Trunk Rotation
Stand with your left side facing a cable pulley station with a handle attached at shoulder height. Grasp the handle with both hands and fully extend the arms. Begin with your torso rotated toward the handle and tension in the cable (i.e. the weight stack is slightly elevated from the resting position). Rotate your torso to the right while keeping your arms fully extended and the handle in line with the center of your chest. Keep your eyes focused on the handle as you rotate, and keep your hips locked forward. Return to the start position without allowing the weight stack to come to rest. Complete 12 repetitions, then reverse your position and repeat the exercise.race.