The core muscles (abdominals and lower back) are critical to athletic performance, and are largely considered the most important muscles in the human body. The core muscles provide a stable platform for the muscle actions of the shoulders, arms, hips, and legs. This is especially important in athletic full body movements that require the core musculature to smoothly transmit force between the upper and lower body. Full body strength is directly dependent on a strong and stable core, and overall the extremities can only be as strong as the core permits them to be.
There are five primary muscle groups that define the core. Each of these muscle groups has an important role in human movement, and must be strategically trained to establish total core strength and stability. All of the core must be targeted in training because the core muscle system will, “only be as strong as the weakest link.”
Five Core Muscles Groups
- The rectus abdominus refers to the traditional “six pack” muscles that extend longitudinally down the abdomen. These muscles are responsible for flexing the spinal column.
- The erector spinae is comprised of a bundle of muscles and tendons that extend throughout the spinal column. These muscles initiate trunk extension.
- The external obliques run diagonally across the abdomen and are located perpendicular to the rectus abdominis and erector spinae. The external oblique’s contribute to trunk flexion, but are primarily responsible for trunk rotation and lateral flexion.
- The internal obliques are located at a right angle underneath the external obliques, and produce similar muscle actions. The internal obliques also assist in compression of the abdomen. *Due to their unique right angle alignment, the internal and external obliques operate as opposite-side rotators. When the trunk rotates left, obliques on the right contract and vice versa.
- The transversus abdominis is a group of deep abdominals that are located underneath the rectus abdominis and run horizontally. These muscles do not initiate movement, but are important for respiration as well as pelvic and spinal stability (operate through compression of the abdomen).
To assure that all of the core muscles are efficiently developed, core training should incorporate an appropriate and equal balance of flexion, extension, lateral flexion, rotation, and abdominal compression movements. This will ensure complete core muscle development that can maximize exercise performance.