Do You Use Your Hip Abductors & Adductors in Running?

Functional Anatomy

No single muscle group works alone in its own cubicle when you run. Although your adductors -- inner thigh muscles -- are traditionally described to move your leg toward the midline of your body, they have little to do with adduction since the muscles don't contract when you adduct your leg. When you run or walk, your adductors stabilize your hips and legs to avoid excessive internal rotation that could cause knee pain or an injury when you run. Because the adductors wrap themselves from the front of the lower pelvic bone to the back of your thigh bone, they help to control hip flexion, extension, abduction, adduction and rotation, according to fitness coach Lisa Bonang. Hip abductors, which include the deep gluteal muscles in your rear, also stabilize your hips when you run rather than moving your leg away from your body's midline -- or abduction. Since your pelvis rotates when your run, both adductors and abductors prevent excessive pelvic internal or external rotation.

Natural Accelerator and Brakes

Besides moving your legs like you're side-kicking someone in the stomach, your hip abductors also assist in hip flexion and extension, which is a common hip movement in running. When you run, the back leg and hip abductors accelerate while your adductors and hamstrings in the front leg decelerate your body like a car brake as you land, explains Bonang. Both muscle groups constantly alternate their functions with each stride.

Stronger Butt May Prevent Injuries

Your knee is a pretty dumb joint since its direction of movement is dictated by your hips. Hip adductors and abductors play a constant tug-of-war game as they constantly maintain hip and knee stability when you run. Too much external hip rotation can cause excess knee abduction. Likewise, too much internal hip rotation can cause them to adduct excessively. In a 2008 study published in the Journal of Sport Rehabilitation, women with weak hip abductors demonstrated greater knee abduction than women with strong hip abductors. Researchers in a study published in the Journal of Applied Biomechanics observed that runners with excessive knee abduction tend to have weaker hip abductors, which places more load on the inner part of the knee when they run. Therefore, strengthening the hip abductors can be one way to prevent knee and hip injuries.

No More "Open and Close"

Although it's tempting to hop on the inner-thigh and outer-thigh machine or the donkey-kick machine to strengthen those muscles, these exercises don't consider the movement factors that control running. A better way to improve adductor and abductor functions is to perform a few exercises that improve hip stability, strength and movement. One such exercise is the single-leg squat, which works on hip abductor strength, adductor and core stability and movement coordination. With your own body weight or with the assistance of a rubber tube or suspension cable, this exercise can determine if one side of your body is stronger and more stable than the other side. If you need to work up to this exercise, researchers suggest the quadruped hip extension, floor bridges, the clam and the sidestep to strengthen your abductors, according to a 2013 study published in the Journal of Orthopaedic & Sports Physical Therapy.