Featured Article: Core Strength
by Charles Stelk, MPT (11/17/03)

What are the core muscles?

The core musculature includes the muscles of the trunk and pelvis that are responsible for maintaining the stability of the entire skeletal structure. These muscles determine your posture while running and in effect link your upper and lower body.

Why is it important to maintain strength in this muscle group?

Theoretically, core strength training will lead to greater maximal power yet more efficient use of the muscles of the shoulders, arms, and legs. The most common technical error in distance running is inefficient upper body movement. Other benefits include improved balance and a lower risk of injury. It has been well documented that insufficient core strength can lead to serious injury of the low back, hip flexors and hamstrings.

How are the core muscles best trained?

Although the core muscles can be strengthened with traditional weight-training exercises, conditioning should eventually mimic the dynamic movements associated with running. Sport specific training should emphasize the running positions that are most critical in competition; relaxed shoulders, anterior pelvic tilt, erect torso, high knees, and ankle dorsiflexion.

ABDOMINALS

Muscle group includes the rectus abdominis, internal and external obliques, transverses abdominus. Strong abdominals provide the foundation for training and strengthening every other muscle in the body. It has been shown through electromyographical study that the abdominal obliques play a major role in running. This muscle group prevents the hips and shoulders from over rotating. The obliques also act to stabilize the connection between leg and arm action. Weak abs can lead to low back pain while performing squats and other lower extremity lifts, poor running form, early fatigue during distance runs and general weakness. Abdominal exercises should be performed daily with emphasis placed on quality not quantity. Generally excepted training methods include crunches, crunches with a twist, decline sit-ups, hanging leg pulls, lateral dumbbell bends, supine straight leg raises, supine bicycling and knee to chest pulls.

LOWER BACK

Muscle group includes the erector spinae, quadratus lumborum, multifidus, rotatores, iliocostalis lumborum and thoracis, paraspinals. Low back pain is generally not a common complaint of the collegiate or high school athlete based on a 2002 study by Nadler, et. al. He found that only 14 of 236 Division I athletes were treated for low back pain prior to strengthening the core muscles. This study is misleading however, because low back pain often times does not present physical pain or deformity until later in life.

Strengthening the lower back can be accomplished with a variety of training methods and techniques including lumbar extensions, prone chest raises, Russians twists and straight leg dead lifts. With all core exercises, especially the low back, it is important to note that increased repetitions with moderate weight is recommended rather than increased weight with fewer reps.

UPPER BACK

Muscle group includes the latissimus dorsi, rhomboids, serratus anterior, trapezius. For runners, the upper back plays a critical role allowing for proper arm swing in sprinters and relaxed shoulders in distance runners. A common finding in female sprinters and distance runners is an abducted arm swing (the arms are maintained in a “chicken wing” position while running). This is most likely due to weak latissimus muscles. Strengthening exercises include lat. pull downs, bent over rows, scapular retraction and shoulder shrugs.

HIP FLEXORS

Muscle group includes the iliopsoas, rectus femoris, sartorius, tensor fasciae latae. In professional sprinters the hip flexor muscle group is always very well defined. This muscle group is critical for maintaining high knees and explosive leg drive while sprinting. In distance runners, the hip flexor can easily fatigue on long runs and lead to injury or dysfunction. Strengthening exercises include lunges in multiple planes (side to side, oblique, and straight ahead), standing hip flexion, running uphill and specific drilling (A's, B's and C's).

This has been a very brief introduction to core strength training. The main focus here is to enhance awareness of the importance of the core muscles and how they relate to running. It is imperative to check with your track coach, strength coach or athletic trainer before initiating any training schedule on your own.