Functional Anatomy of the Core

07 Oct Functional Anatomy of the Core

The Core is an anatomical area of the body pertaining to sports performance training, the development of speed, and rotary movement patterns such as hitting, throwing, striking, or swinging. The core is a vital component of the kinetic chain, rotary movement patterns, and the development of the athlete.

What is typically not mentioned in reference to the core is a defining the anatomical structures and functional anatomy of these structures. To better understand the involvement of the core in sports performance and how to correctly train this anatomical area of the kinetic chain defining the anatomical structures of this body segment is imperative.


In basic terms, the Core is a reference to an anatomical area of the body. It is comprised of all the neuromuscular and skeletal components of the lumbo/pelvic/hip complex. It is also associated with muscular structures of the lower back, abdominals, obliques, and hips. The core functions as a unit to produce force, reduce force, stabilize the entire kinetic chain, and transfer energy developed by the lower extremities to upper extremities. (Michael Clark, Integrated Core Stabilization Training, 9)

Strength and conditioning programs address the development of stability, endurance, and power within the core. Stability is defined as the ability of any system to remain unchanged or aligned in the presence of outside forces (Greg Rose, Titleist Performance Institute Manual, 86) Development of stability within the core is contingent upon muscular strength. Strength is defined as the ability of a muscular system to exert the required levels of force to perform the functional movement at hand. (Michael Clark, Integrated Training for the New Millenium, 369) Endurance is the ability of the neuromuscular system to perform a repetitive movement pattern withouth fatigue, and power can be defined as the ability of the body to create the greatest amount of force in a short amount of time. (Vladimir Zatsiorsky, Professor, Department of Exercise and Sport Science, Pennsylvania State Univeristy) Stability, strength, endurance, and power are created in the core through a comprehensive core training program.

The first step in the creation of a comprehensive core program is understanding the functional anatomy of the structures associated with this section of the body. The functional anatomy of the core will contain all articular and soft tissue structures associated with the lumbo-pelvic-hip complex. The articular structures associated with the core encompass the pelvis, femur, sacrum, and lumbar spine. The corresponding soft tissues associated with these articular structure will encompass the upper leg, gluteal region, and lumbo-pelvic-hip complex.

Anterior Lumbo-Pelvic-Hip Complex

The anterior portion of the pelvis-sacral-lumbar spine is constructed of musculature commonly referred to as the core. The anterior portion of the core consists primarily of the Abdominal Grouping. This contains the transverse abdominus, rectus abdominus, internal oblique, and external oblique. The most superficial grouping of the abdominal grouping, the rectus abdominus, functions primarily as a flexor of the trunk, stabilizer of the lumbar spine, and decelerator of spine extension. The internal and external olbiques are rotators of the trunk in addition to stabilizing the lumbo-pelvic-hip complex. The obliques are also involved in the deceleration of spine extension and rotation. The deepest layer of the abdominal grouping, the transvers abdominus, wraps around the entire core. The function of this muscle is to stabilization of the lumbo-pelvic-hip complex.

Posterior Lumbo-Pelvic-Hip Complex

The Iliopsoas is comprised of the iliacus, psoas major, and psoas minor. The primary function of the illiopsoas is a flexor of the hip and stabilizer of the lumbar spine. These muscles also function in the deceleration of hip extension and internal rotation. The Quadratus Lumborum (QL) is located in the posterior lumbo-/pelvis-/hip complex. The QL functions to laterally flex and extend the spine. The QL is often associated with lower back pain as a result of its attachment points and the recruitment of this muscle when the erector spinae are weak or inhibited.

The Erector Spinae is comprised of the iliocostalis, spinalis, and iliocostals; it attaches at the sacrum, illium, lumbar spine, and thoracic spine. The function of these muscles is extension of the vertebrae. Integrated within the kinetic chain these muscles stabilize the lumbar spine in addition to decelerating flexion and rotation.

Anterior Upper Leg

The anterior upper leg contains the Quadriceps; a grouping of five individual muscles. The rectus femoris, vastus lateralis, vastus intermedius, and vastus medialis comprise the quadriceps. The Sartorius and Iliopsoas are additionly found in the anterior portion of the upper leg. The rectus femoris is a primary extensor of the knee and the rectus femoris is a flexor of the hip. The sarotius is a flexor and rotator of the hip in addition to flexion of the knee. The iliopsoas is a strong hip flexor. The integrated function of the quadriceps, sartoirus, and iliopsoas is stabilization of the knee and hip, deceleration of knee flexion, abduction, internal rotation, and deceleration of hip extension.

Posterior Upper Leg

The Hamstrings are the primary grouping of muscles of the posterior upper leg. The hamstrings are comprised of the semimembranosus, semitendinosus, and biceps femoris. The hamstring complex is an extensor of the hip joint and a flexor of the knee. The integrated function of the hamstrings is as stabilizers of both the hip and knee during movement and decelerators of knee extension.

Medial Upper Leg

The medial upper leg consists primarily of the Adductors of the hip and leg. The pectineus, adductor longus, brevis, magnus, and gracilias are the primary musculature of the medial thigh responsible for adducting, flexing, and internally rotating of the femur. In addition, the adductor complex stabilizes the hip and acts as a decelerator of hip flexion.

Gluteal Region

The gluteal region is comprised of the musculature of the posterior and lateral portions of the pelvis and upper leg. The Gluteal muscles are comprised of the gluteus maximus, medius, minimus and are arranged in three layers. The gluteus maximus is the most superficial of the three muscles and is a primary extensor, and lateral rotator of the hip. The gluteus medius is located laterally on the hip. It creates abduction, and medial rotation of the hip in addition to stabilizing the pelvis. The gluteus minimus is the deepest layer of the three gluteal muscles and is an abductor, medial rotator, and stabilizer of the hip.


A comprehensive review of the functional anatomy associated with the core region indicates the  neuromuscular system is integrated in terms of functional movement. The core is an anatomical section of the body operating in conjunction with the entire kinetic chain to produce and reduce force, and stabilize during functional movement patterns. In order for optimal function to occur in within sports performance, both the isolated and integrated function of each muscle within the kinetic chain must be efficient. A sound understanding of these principles and how each muscle operates allows for the fitness professional to assess the kinetic chain, develop corrective exercise strategies, and boost physical performance.

About Performance Coach Sean Cochran: Sean Cochran, one of the most recognized performance coaches in sports today. A career spanning positions with 2 major league baseball organizations, over 10 years on the PGA Tour and work with top professionals including three-time Masters, PGA, and British Open Champion Phil Mickelson, future hall of fame Trevor Hoffman, and Cy Young award winner Jake Peavy provides Sean a proven track record of success.  He has been involved in the production of numerous performance videos and authored books including; Performance Golf Fitness, Complete Conditioning for Martial Arts, and Fit to Hit. He has been a presenter of educational seminars for numerous organizations including the world renown Titleist Performance Institute.

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