To stay on the cutting edge of research, science, and practical application, the health and fitness professional needs to follow a comprehensive, systematic, and integrated approach when training, reconditioning, or rehabilitating a client. In order to develop a comprehensive integrated training program, the health and fitness professional must fully understand the functional kinetic chain.2 An integrated training program is a comprehensive approach that strives to improve all the components necessary to achieve optimum performance (strength, balance, flexibility, endurance, and power). Since the core is where the human body’s center of gravity is located and where all movement begins,46,47, 81,82 this article focuses on the fundamental concepts of core stabilization, and how the health and fitness professional can design an effective and dynamic core stabilization program.10,15,22,23, 34,42,58
Traditionally, training has focused on isolated, absolute strength gains in isolated muscles, utilizing single planes of motion. However, all functional activities are multi-planar and require acceleration, deceleration, and dynamic stabilization.32,42,58 Movement may appear to be single plane dominant, but the other planes need to be dynamically stabilized to allow for optimum neuromuscular efficiency.2 Understanding that functional movements require a highly complex, integrated system enables the health and fitness professional to make a paradigm shift. The paradigm shift focuses on training the entire kinetic chain utilizing all planes of movement, while establishing high levels of functional strength and neuromuscular efficiency.18,64,69,73,81,93 The paradigm shift also dictates that the health and fitness professional train force reduction, force production and dynamic stabilization during all kinetic chain activities.12,34
A core stabilization training program improves dynamic postural control, ensures appropriate muscular balance and joint arthrokinematics around the lumbo-pelvic-hip complex, and allows for the expression of dynamic functional strength and improve neuromuscular efficiency throughout the entire kinetic chain.2,12,18,34,36,42,63,64,68,71,72,73,92,93
BENEFITS OF CORE STABILIZATION TRAINING
- Improve dynamic postural control
- Ensure appropriate muscular balance and joint arthrokinematics
- Allow for the expression of functional strength
- Provide intrinsic stability to the Lumbo-Pelvic-Hip Complex, which allows for optimum neuromuscular efficiency of the rest of the Kinetic Chain
Core Stabilization Concepts
The core is defined as the lumbo-pelvic-hip complex.2,34 There are 29 muscles that attach to the lumbo-pelvic-hip complex.7,8,34,86 An efficient core allows for the maintenance of optimum length-tension relationships of functional agonists and antagonists, which makes it possible for the body to maintain optimum force couple relationships in the lumbo-pelvic-hip complex. Maintaining optimum length-tension relationships and force-couple relationships allows for the maintenance of optimum joint arthrokinematics in the lumbo-pelvic-hip complex during functional kinetic chain movements. 92,93,98 This provides optimum neuromuscular efficiency in the entire kinetic chain, and allows for optimum acceleration, deceleration, and dynamic stabilization during integrated, dynamic movements.2,34,46,47,55,58,81,82,92,93
The core operates as an integrated functional unit, enabling the entire kinetic chain to work synergistically to produce force, reduce force, and dynamically stabilize against abnormal force.2 In an efficient state, each structural component distributes weight, absorbs force, and transfers ground reaction forces.2 This integrated, interdependent system needs to be appropriately trained to enable it to function efficiently during dynamic activities.
Many individuals have developed functional strength, power, neuromuscular control, and muscular endurance in specific muscles that enable them to perform functional activities.2,34,54,58 However, few people develop the muscles required for spinal stabilization.53,54,55 The body’s stabilization system has to function optimally to effectively utilize the strength, power, neuromuscular control, and muscular endurance that it has developed in its prime movers. If the extremity muscles are strong and the core is weak, there will not be enough force created to produce efficient movements. A weak core is a fundamental problem inherent to inefficient movement that leads to predictable patterns of injury.53,54,55,58
The core musculature is an integral component of the protective mechanism that relieves the spine of deleterious forces that are inherent during functional activities.18 A properly designed core stabilization training program helps an individual gain strength, neuromuscular control, power, and muscle endurance of the lumbo-pelvic hip complex. This integrated approach facilitates balanced muscular functioning of the entire kinetic chain.2 Greater neuromuscular control and stabilization strength provides a more biomechanically efficient position for the entire kinetic chain, and thereby allows optimum neuromuscular efficiency throughout the kinetic chain.
Neuromuscular efficiency is established by the appropriate combination of postural alignment (static/dynamic) and stability strength, which enables the body to decelerate gravity, ground reaction forces, and momentum.12,42,64 If the neuromuscular system is not efficient, it will be unable to respond to the demands placed on it during functional activities.2 As the efficiency of the neuromuscular system decreases, the ability of the kinetic chain to maintain appropriate forces and dynamic stabilization decreases significantly. This decreased neuromuscular efficiency leads to compensation and substitution patterns, (synergistic dominance, reciprocal inhibition, arthrokinetic inhibition) as well as poor posture during functional activities.36,92,93 This leads to increased mechanical stress on the contractile and non-contractile tissue and leads to repetitive microtrauma, abnormal biomechanics, and injury.18,36,69,70
To fully understand functional core stabilization training and rehabilitation, the health and fitness professional must fully understand functional anatomy, lumbo-pelvic-hip complex stabilization mechanisms, and normal force couple relationships.5,7,8,86
A review of the key lumbo-pelvic-hip complex musculature enables the health and fitness professional to understand functional anatomy and develop an integrated training program. Lumbo-pelvic-hip complex musculature includes the inner unit and the outer unit .
THE INNER UNIT
- Tranverse Abdominus
- Internal Oblique
- Lumbar Transversospinalis
THE OUTER UNIT
- Rectus Abdominus
- External Oblique
- Erector Spinae
- Quadratus Lumborum
- Adductor Complex
- Gluteus Maximus
The key lumbar spine muscles include the transversospinalis group, erector spinae, quadratus lumborum, and latissimus dorsi. The key abdominal muscles include the rectus abdominus, external oblique, internal oblique, and transverse abdominus. The key hip musculature includes the gluteus maximus, gluteus medius, and psoas. It is very important for the health and fitness professional to understand that muscles function as an integrated unit. The central nervous system is designed to optimize the selection of muscle synergies, not isolated muscles.
All of these muscles play an integral role in the kinetic chain because they provide dynamic stabilization and optimum neuromuscular control of the entire lumbo-pelvic-hip complex. When isolated, these muscles do not effectively achieve stabilization of the lumbo-pelvic-hip complex. It is the synergistic, interdependent functioning of the entire lumbo-pelvic-hip complex that enhances the stability and neuromuscular control throughout the entire kinetic chain.
The core maintains postural alignment and dynamic postural equilibrium during functional activities. Optimum alignment of each body part is a cornerstone to an integrated training and rehabilitation program. Optimum posture and alignment allows for optimum neuromuscular efficiency because the normal length-tension relationship, force-couple relationship, and arthrokinematics are maintained during functional movement patterns.18,34,36,58,61,62,63,66,69,73,92,93 A comprehensive core stabilization program prevents the development of serial distortion patterns and provides optimum dynamic postural control during functional movements.18,34,58,71,72
A strong and stable core can improve optimum neuromuscular efficiency by improving dynamic postural control.51,53,55,65,88,92,93 Several authors have demonstrated kinetic chain imbalances in individuals with altered neuromuscular control.9,16,17,18,53,54,55,56,60,61,62,63,64,68,69,70,71,72,73,79,80,88,93 Research has demonstrated that people with low back pain have an abnormal neuromotor response of the trunk stabilizers accompanying limb movement.53,54,79 Additionally, individuals with low back pain had significantly greater postural sway and decreased limits of stability. Research also demonstrates that approximately 75-90% of all individuals suffer from recurrent episodes of back pain. Furthermore, it has been demonstrated that individuals have decreased dynamic postural stability in the proximal stabilizers of the lumbo-pelvic-hip complex following lower extremity ligamentous injuries.9,16,17,18 It has also been demonstrated that joint and ligamentous injury can lead to decreased muscle activity.33,36,95,98 Joint and ligament injury can lead to joint effusion, which in turn leads to muscle inhibition.33 This alters neuromuscular control in other segments of the kinetic chain secondary to altered proprioception and kinesthesia.9,16 Therefore, when an individual has pain and swelling, all of the muscles that cross that joint can be inhibited.
Research has also demonstrated that muscles can be inhibited from an arthrokinetic reflex.18,68,95,98 This is referred to as athrogenic muscle inhibition. Arthrokinetic reflexes are reflexes that are mediated by joint receptor activity. If an individual has abnormal arthrokinematics, the muscles that move the joint will be inhibited. For example, if an individual has a sacral torsion, the multifidus and the gluteus medius can be inhibited.52 This leads to abnormal movement in the kinetic chain. The tensor fascia latae become synergistically dominant and become the primary frontal plane stabilizer.86 This often leads to tightness in the iliotibial band, which decreases frontal and transverse plane control at the knee. Furthermore, if the multifidus is inhibited,52 the erector spinae and the psoas become facilitated. This will further inhibit the inner unit stabilization mechanism (internal oblique and transverse abdominus) and the gluteus maximus,53,54 which also decreases frontal and transverse plane stability at the knee. As previously mentioned, an efficient core improves neuromuscular efficiency of the entire kinetic chain because it dynamic stabilizes the lumbo-pelvic-hip complex and therefore improves pelvo-femoral biomechanics. This is yet another reason that training programs should include a comprehensive core stabilization-training program to prevent injury as well as the chain reactions that are initiated secondary to injury in the kinetic chain.
Assessment of the Core
Before a health and fitness professional implements a comprehensive core stabilization program, an individual must undergo a comprehensive Kinetic Chain Assessment.
Since muscle imbalances and arthrokinematic deficits sometimes cause abnormal movement patterns to develop throughout the entire kinetic chain, it is extremely important to thoroughly assess each individual with a kinetic chain dysfunction for muscle imbalances and arthrokinematic deficits. It is beyond the scope of this article to thoroughly explain a comprehensive kinetic chain assessment. (It is recommended that the interested reader see NASM Kinetic Chain Assessment home study course.)
Scientific Rationale for Core Stabilization Training
Most individuals train their core stabilizers inadequately compared to other muscle groups.2 Although adequate strength, power, muscle endurance, and neuromuscular control are important for lumbo-pelvic-hip stabilization, it is detrimental to perform exercises incorrectly or that are too advanced. Several authors have found decreased firing of the transverse abdominus, internal oblique, multifidus, and deep erector spinae in individuals with chronic low back pain.53,54,55,56,79,87 Performing core training with inhibition of these key stabilizers leads to the development of muscle imbalances and inefficient neuromuscular control in the kinetic chain. Research demonstrates that abdominal training without proper pelvic stabilization increases intradiscal pressure and compressive forces in the lumbar spine.4,10,53,54,55,56,77,78 Additional research demonstrates that hyperextension training without proper pelvic stabilization can increase intradiscal pressure to dangerous levels, cause buckling of the ligamentum flavum, and lead to narrowing of the intervertebral foramen.4,10,78
Research also demonstrates decreased stabilization endurance in individuals with chronic low back pain.10,19,46,47 The core stabilizers are primarily type I slow twitch muscle fibers.46,47,81,82 These muscles respond best to time under tension. Time under tension is a method of contraction that lasts for 6-20 seconds and emphasizes hyper-contractions at end ranges of motion. This method improves intramuscular coordination, which improves static and dynamic stabilization. To get the appropriate training stimulus, you must prescribe the appropriate speed of movement for all aspects of exercises.22,23 Core strength endurance must be trained appropriately to allow an individual to maintain dynamic postural control for prolonged periods of time.4
In addition, research demonstrates decreased cross sectional area of the multifidus in subjects with LBP.52 Researchers found that there was not spontaneous recovery of the multifidus following resolution of symptoms.52 Moreover, research shows that traditional curl up increases intradiscal pressure and increases compressive forces at L2-L3.4,10,77,78
Additional research demonstrates increased EMG activity and increased pelvic stabilization when an abdominal drawing-in maneuver was performed prior to initiating core training.4,10,15,23,50,51,56,76,80,88 Also, maintaining the cervical spine in a neutral position during core training will improve posture, muscle balance, and stabilization. If the head protracts during movement, the sternocleidomastoid is preferentially recruited. This increases the compressive forces at the C0-C1 vertebral junction. This can also lead to pelvic instability and muscle imbalances secondary to the pelvo-occular reflex. This reflex is important to maintain the eyes level.68,69 If the sternocleidomastoid muscle is hyperactive and extends the upper cervical spine, then the pelvis will rotate anteriorly to re-align the eyes. This can lead to muscle imbalances and decreased pelvic stabilization.68,69
Guidelines for Core Stabilization Training
Prior to performing a comprehensive core stabilization program, each individual must undergo a comprehensive Kinetic Chain Assessment. All muscle imbalances and arthrokinematic deficits need to be corrected prior to initiating an aggressive core-training program. A team approach is the best way to thoroughly assess each client. Find a competent health care professional in your community that you can establish a referral basis with for comprehensive evaluations.
Core Stabilization Training Guidelines
- Activity Specific
- Proprioceptively Challenging
- Based on Current Science
- Plane of motion
- Range of motion
- Loading parameters (physioball, ball, weight vest, dumbbell, tubing, etc.)
- Body position
- Amount of control
- Speed of execution
- Amount of feedback
- Duration (sets, reps, tempo, Bodyblade, power sports trainer, time under tension)
INTEGRATED FUNCTIONAL TRAINING CONTINUUM
- Multi-planar (3 planes of motion)
- Utilize the entire muscle contraction spectrum
- Utilize the entire contraction velocity spectrum
- Manipulate all acute training variables
(Sets, reps, intensity, rest intervals, frequency, duration)
MULTI-MODAL LOADING PARAMETERS
- Stability Ball 5. Power Balls
- Cable (Free motion) 6. Body Blades
- Tubing 7. Dumbells
- Medicine Ball 8. Weight Vests
A comprehensive core stabilization training program should adhere to specific guidelines. It should be systematic, progressive and functional. The program should emphasize the entire muscle contraction spectrum, focusing on force production (concentric contractions), force reduction (eccentric contractions), and dynamic stabilization (isometric contractions). The core stabilization program should begin in the most challenging environment the individual can control.
Exercise Selection Criteria
- Systematic (Integrated Functional Continuum)
- Proprioceptively Enriched
- Activity Specific
A progressive continuum of function that adheres to multi-modal loading parameters should be followed to systematically train the individual. The program should be manipulated regularly by changing any of the following variables: plane of motion, range of motion, loading parameters (physioball, ball, body blade, power sports trainer, weight vest, dumbbell, tubing, etc), body position, amount of control, speed of execution, amount of feedback, duration (sets, reps, tempo, time under tension), and frequency.2,10,12,15,17,22,23,24,29,34,42,45,50, 56,58,59,64,65,73,74, 75,76,78,80,87,88,89, 90,91,93
When designing core stabilization training program, the health and fitness professional should create a proprioceptively enriched environment and select the appropriate exercises to elicit a maximal training response. The exercises must be safe, challenging, stress multiple planes, incorporate a multi-sensory environment, be derived from fundamental movement skills, and be activity specific.
The health and fitness professional should follow a progressive and integrated functional continuum to allow optimum adaptations.34,42,50,58
In addition, the health and fitness professional should follow an exercise progression continuum. The following concepts are critical for a proper exercise progression: slow to fast, simple to complex, known to unknown, low force to high force, eyes open to eyes closed, static to dynamic, correct execution to increased reps/ sets/intensity.22,23,34,42,50,58
EXERCISE PROGRESSION CONTINUUM
- Slow → Fast
- Known → Unknown
- Stable → Controlled → Dynamic Functional
- Low Force → High Force
- Correct Execution → Increased Intensity
The goal of core stabilization is to develop optimal levels of functional strength and dynamic stabilization.2,10 Neural adaptations become the focus of the program instead of striving for absolute strength gains.18,34,55,64,80 Increasing proprioceptive demand by utilizing a multi-sensory, multi-modal environment becomes more important then increasing the external resistance. Quality of movement is stressed over quantity.
Core stabilization training is specifically designed to improve core stabilization and neuromuscular efficiency. The health and fitness professional must be concerned with the sensory information that stimulates the central nervous system. The health and fitness professional that allows their clients to train with poor technique and poor neuromuscular control, may cause the development of poor motor patterns and poor stabilization.34,58 The focus of the program must be on function. 34,42,58
Core Stabilization Training Program
The following is an example of an integrated core stabilization-training program. The individual begins at the highest level at which they are able to maintain stability and optimum neuromuscular control. They are progressed through the program when they achieve mastery of the exercises in the previous level.1,2,4,10,12,15,17,18,22,23,24,25,29,34,39,42,43,44,45,46,47,48,55,56,58,64,65,73,78,80,90,91
Level I (Stabilization)
The exercises in Level I involve little joint motion and are primarily designed to improve intrinsic stabilization and provide optimum neuromuscular control for the lumbo-pelvic hip complex.
Level II (Strength)
Isometric stabilization activities are replaced with dynamic concentric and eccentric activities through the full range of motion. A multi-planar, multi-dimensional progression is initiated. This phase is also designed to follow the integrated functional continuum. The specificity, speed, and neural demand of the exercises are progressed. Total kinetic chain neuromuscular efficiency is enhanced by providing maximum proprioceptive stimulation to the CNS during integrated functional movements while maintaining optimum stabilization of the entire lumbo-pelvic-hip complex.
Level III (Power)
The entire muscle action spectrum and contraction velocity spectrum is utilized during integrated functional movements. The individual performs specific exercises at a similar intensity and similar rate of force production that the individual will be exposed to upon return to their environment.
Example Core Stabilization Training Program
||Choose 2-4, Level I
||1-3 x 12-20
||Choose 1, Level I and 2,
|2-3 x 8-12
||Choose 2-3, Level II
||2-3 x 8-10
||Choose 2-4, Level II
||3 x 12-15
||Choose 2-4, Level
||3 x 6-10
||Choose 2-4, Level III
||3-4 x 5-10
||Choose 3-5, Level III
||3-5 x 3-5
- Iso-Ab Prone
- Floor Bridging
- Quadruped Opposite
- Arm/Leg Raise
- 3 x 10-20
- 3 x 10-15
- 3 x 10-15
- Prone Iso-Ab with
- Hip Extension
- Ball DB Crunch
- Ball DB Bridge
- Ball DB Cobra
|3 x 8-12
- Ball Push-Ups
- Reverse Hypers
- Cable PWF
|3 x 8-10
- Back Extension
- Reverse Crunch
- Cable Rotation
- DB Multi-Plane Lunge and Press
|3 x 10-12
- DB Step and Press
- Medicine Ball Rotation
- Cable Extension Deceleration
|3 x 6-8
- MB PNF
- Cable Rotation
- Single Leg Chest Press
|3 x 8-10
- OH MB Throw
- Rotation Chest Pass
- PB Wall Hits
|3-4 x 3-5
A core stabilization program should be included in all integrated training programs. A core stabilization training program enables an individual to gain optimum neuromuscular control of the lumbo-pelvic-hip complex and to achieve optimum performance.
- Aaron G: Clinical Guideline Manual for Spine. Healthsouth Corporation 1996.
- Aaron G: The Use of Stabilization Training in the Rehabilitation of the Athlete. Sports Physical Therapy Home Study Course, 1996.
- Aruin As, Latash ML: Directional Specificity of Postural Muscles in Feed-Forward Postural Reactions During Fast Voluntary Arm Movements. Exp Brain Res 103:323-332, 1995.
- Ashmen KJ, Swanik CB, Lephart SM: Strength and Flexibility Characteristics of Athletes with Chronic Low Back Pain. Journal of Sports Rehabilitation 5:275-286, 1996.
- Aspden RM: Review of the Functional Anatomy of the Spinal Ligaments and the Erector Spinae Muscles. Clin Anat. 5:372-387, 1992.
- Axler CT, McGill SM: Low Back Loads Over a Variety of Abdominal Exercises; Searching for the Safest Abdominal Challenge. Med Sci Sports Exerc 29(6):804-810, 1997.
- Basmajian J: Muscles Alive. Baltimore, Williams and Wilkins, 1974.
- Basmajian J: Muscles Alive; Their Functions Revealed by EMG. (5th ed). Baltimore, Williams and Wilkins, 1985.
- Beckman SM, Buchanan TS: Ankle Inversion and Hypermobility: Effect on Hip and Ankle Muscle Electromyography Onset Latency. Arch Phys Med Rehabil 76(12):1138-1143, 1995.
- Beim G, Giraldo JL, Pincivero DM, Borror MJ, FU FH: Abdominal Strengthening Exercises: A Comparative EMG Study. Journal of Sport Rehabilitation 6:11-20, 1997.
- Beimborn DS, Morrissey MC: A Review of the Literature Related to Trunk Muscle Performance. Spine 13(6):655-670, 1988.
- Blievernicht J: Balance; Course Manual. Chicago, IL 1996.
- Boduk N, Twomey L: Clinical Anatomy of the Lumbar Spine. New York, Churchill Livingstone 1987.
- Bousiett S, Zattara M: A Sequence of Postural Adjustments Precedes Voluntary Movement. Neurosci Lett 22:263-270, 1981.
- Bittenham D, Brittenham G: Stronger Abs and Back. Human Kinetics. Champaign, IL 1997.
- Bullock-Saxton JE: Local Sensation Changes and Altered Hip Muscle Function Following Severe Ankle Sprain. Physical Therapy 74(1):17-23, 1994.
- Bullock-Saxton JE, Janda V, Bullock M: Reflex Activation of Gluteal Muscles in Walking; An Approach to Restoration of Muscle Function for Patients with Low Back Pain. Spine 18(6):704-708, 1993.
- Bullock-Saxton JE: Muscles and Joint: Inter-Relationships with Pain and Movement Dysfunction. Course Manual, Novemeber 1997.
- Calliet R: Low Back Pain Syndrome. Oxford, Blackwell, 1962.
- Chaitow L: Soft Tissue Manipulation. Rochester, Healing Arts Press, 1991.
- Chaitow L: Muscle Energy Techniques. New York, Churchill Livingstone, 1997.
- Check P: Scientific Back Training. Correspondence Course. Paul Chek Seminars. LaJolla, CA 1994.
- Chek P: Scientific Abdominal Training. Correspondence Course. Paul Chek Seminars. LaJolla,CA 1992.
- Chek P: Swiss Ball Training. Correspondence Course. Paul Chek Seminars. LaJolla, CA 1996.
- Chek P: Dynamic Medicine Ball Training. Correspondence Course. Paul Chek Seminars. LaJolla, CA 1996.
- Chek P: Program Design. Correspondence Course. Paul Chek Seminars. LaJolla, CA 1995.
- Chek P: Strong and Stable. 3 volume video series. Paul Chek Seminars. LaJolla, CA 1995.
- Cook G, Fields K: Functional Training for the torso. Internet access. WWW.Funct.html, 1998.
- Creager C: Therapeutic Exercise Using Foam Rollers. Executive Physical Therapy. Berthoud, CO 1996.
- Cresswell AG, Grundstrom H, Thorstensson A: Observations on Intra-Abdominal Pressure and Patterns of Abdominal Intra-Muscular Activity in Man. Acta Physiol Scand 144:409-418, 1992.
- Cresswell AG, Oddson L, Thorstensson A: The Influence of Sudden Perturbations on Trunk Muscle Activity and Intra-Abdominal Pressure While Standing. Exp Brain Res 98:336-341, 1994.
- Crisco J, Panjabi MM: The Intersegmental and Multisegmental Muscles of the Lumbar Spine. Spine 16:793-799, 1991.
- DeAndre JR, Grant C, Dixon ASJ: Joint Distension and Reflex Muscle Inhibition in the Knee. J Bone Joint Surg (Am) 47:313-322, 1965.
- Dominguez RH: Total Body Training. Moving Force Systems. East Dundee, IL 1982.
- Dvorak J, Dvorak V: Manual Medicine-Diagnostics. New York, George Theim Verlag, 1984.
- Edgerton VR, Wolf S, Roy RR: Theoretical Basis for Patterning EMG Amplitudes to Assess Muscle Dysfunction. Med Sci Sports Exerc 28(6):744-751, 1996.
- Evjenth O: Muscle Stretching in Manual Therapy. Sweden, Alfta Rehab, 1984.
- Fairbank JCT, O’Brien JP: The Abdominal Cavity and the Throacolumbar Fascia as Stabilizers of the Lumbar Spine in Patients with Low Back Pain. Engineering aspects of the spine, London 1980.
- Freeman MAR: Coordination Exercises in the Treatment of Functional Instability of the Foot. Phys Ther 44:393-395, 1964.
- Friedeli WG, Cohen L, Hallet M, Stanhope S, Simon SR. Postural Adjustments Associated with Rapid Arm Movements. II: Biomechanical Analysis.
- Freyette: Principles of Osteopathic Technique. Yearbook of the Academy of Applied Osteopathy, 1954.
- Gambetta V: Building the Complete Athlete; Course Manual. Chicago, IL 1996.
- Gambetta V: Following a Functional Path. Training and Conditioning 5(2):25-30, 1995.
- Gambetta V: Everything in Balance. Training and Conditioning 1(2):15-21, 1996.
- Gambetta V: The Complete Guide to Medicine Ball Training. Optimum Sports Training. Sarasota, FL 1991.
- Gracovetsky S, Farfan H. The Optimum Spine. Spine 11:543-573, 1986.
- Gracovetsky S, Farfan H, Heuller C. The Abdominal Mechanism. Spine 10:317-324, 1985.
- Gray GW: Chain Reaction Festival; Course manual. Chicago, IL 1996.
- Greenman PE: Principles of Manual Medicine. Baltimore, Williams and Wilkins, 1991.
- Gustavsen R, Streeck R: Training Therapy; Prophylaxis and Rehabilitation. New York, Thieme Medical Publishers 1993.
- Hall T, David A, Geere J, Salvenson K: Relative Recruitment of the Abdominal Muscles during Three Levels of Exertion During Abdominal Hollowing. Manipulative Physiotherapists Association of Australia. Gold Coast, Queensland 1995.
- Hides JA, Stokes MJ, Saide M, Jull GA, Cooper DH: Evidence of Lumbar Multifidus Wasting Ipsilateral to Symptoms in Subjects with Acute/Subacute Low Back Pain. Spine 19:165-177, 1994.
- Hodges PW, Richardson CA: Neuromotor Dysfunction of the Trunk Musculature in Low Back Pain Patients. In: Proceedings of the International Congress of the World Confederation of Physical Therapists, Washington, DC 1995.
- Hodges PW, Richardson CA: Inefficient Muscular Stabilization of the Lumbar Spine Associated with Low Back Pain. Spine 21(22):2640-2650, 1996.
- Hodges PW, Richardson CA: Contraction of the Abdominal Muscles Associated with Movement of the Lower Limb. Phys Ther 77:132-14, 1997.
- Hodges PW, Richardson CA, Jull G: Evaluation of the Relationship Between Laboratory and Clinical Tests of Transverse Abdominus Function. Physiotherapy Research International 1:30-40, 1996.
- Holt LE: Scientific Stretching for Sport. Halifax, Dalhouise University Press, 1976.
- Jesse J: Hidden Causes of Injury, Prevention, and Correction for Running Athletes. The Athletic Press. Pasadena, CA 1977.
- Kennedy B: An Australian Program for Management of Back Problems. Physiotherapy 66:108-111, 1980.
- Janda V: Muscle Function Testing. London, Butterworths, 1983.
- Janda V: Physical Therapy of the Cervical and Thoracic Spine. In Grant R (ed). New York, Churchill Livingstone, 1988.
- Janda V: Muscles, Central Nervous System Regulation and Back Problems. In Korr IM (ed): Neurobiologic Mechanisms in manipulative therapy. New York, Plennum Press 1978.
- Janda V: Muscle Weakness and Inhibition in Back Pain Syndromes. In Grieve GP; Modern Manual Therapy of the vertebral column. New York, Churchill Livingstone, 1986.
- Janda V, Vavrova M: Sensory Motor Stimulation Video. Body Control Systems. Brisbane, Australia 1990.
- Jull G, Richardson CA, Comerford M: Strategies for the Initial Activation of Dynamic Lumbar Stabilization. Proceedings of Manipulative Physiotherapists Association of Australia. New South Wales 1991.
- Jull G, Richardson CA, Hamilton C, Hodges PW, NG J: Towards the Validation of a Clinical Test for the Deep Abdominal Muscles in Back Pain Patients. Manipulative Physiotherapists Association of Australia. Gold Coast, Queensland, 1995.
- Lavender SA, Tsuang YH, Andersson GBJ: Trunk Muscle Activation and Co-Contraction While Resisting Movements in a Twisted Posture. Ergonomics 36:1145-1157, 1993.
- Lewit K: Muscular and Articular Factors in Movement Restriction. Manual Medicine 1:83-85.
- Lewit K: Manipulative Therapy in the Rehabilitation of the Locomotor System. London, Butterworths 1985.
- Lewit K: Myofascial Pain; Relief by Post-Isometric Relaxation. Arch Phys Med Rehabil 65:452, 1984.
- Liebenson CL: Active Muscle Relaxation Techniques. Part I. Basic Principles and Methods. J Manipulative Physiol Ther 12(6):446-454, 1989.
- Liebension CL: Active Muscle Relaxation Techniques. Part II. Clinical Application. J Manipulative Physiol Ther 13(2), 1989.
- Liebenson CL: Rehabilitation of the Spine. Baltimore, Williams and Wilkins, 1996.
- Mayer TG, Gatchel RJ: Functional Restoration for Spinal Disorders. The sports medicine approach. Philadelphia, Lea and Febiger 1988.
- Mayer-Posner J: Swiss Ball Applications for Orthopedic and Sports Medicine. Ball Dynamics International. Denver, CO 1995.
- Miller MI, Medeiros JM: Recruitment of the Internal Oblique and Transverse Abdominus Muscles on the Eccentric Phase of the Curl-Up. Phys Ther 67(8):1213-1217, 1987.
- Nachemson A: The Load on the Lumbar Discs in Different Positions of the Body. Clinical Orthopedics 45:107-122, 1966.
- Norris CM: Abdominal Muscle Training in Sports. Br J Sports Med 27(1):19-27, 1993.
- O’Sullivan PE, Twomey L, Allison G, Sinclair J, Miller K, Knox J: Altered Patterns of Abdominal Muscle Activation in Patients with Chronic Low Back Pain. Australian Journal of Physiotherapy 43(2):91-98, 1997.
- O’Sullivan PE, Twomey L, Allison G: Evaluation of Specific Stabilizing Exercises in the Treament of Chronic Low Back Pain with Radiological Diagnosis of Spondylolisthesis. Manipulative Physiotherapists Association of Australia. Gold Coast, Queensland 1995.
- Panjabi MM: The Stabilizing System of the Spine. Part I: Function, dysfunction, adaptation, and enhancement. J Spinal Disord 5:383-389, 1992.
- Panjabi MM, Tech D, White AA: Basic Biomechanics of the Spine. Neurosurgery 7:76-93, 1980.
- Paquet N, Malouin F, Richards CL: Hip-Spine Movement Interaction and Muscle Activation Patterns During Sagittal Trunk Movements in Low Back Pain Patients. Spine 19(5):596-603, 1994.
- Peck D, Buxton DF, Nitz AJ: A Comparison of Spindle Concentrations in Large and Small Muscles Acting in Parallel Combinations. J Morphology 180:243-252, 1984.
- Pope M, Frymoyer J, Krag M: Diagnosing Instability. Clinical Orthopedics and Related Research 296:60-67, 1992.
- Porterfield JA, DeRosa C: Mechanical Low Back Pain; Perspectives in Functional Anatomy. Philadelphia, WB Saunders 1991.
- Richardson CA, Jull G: Muscle Control — Pain Control. What Exercises Would you Prescribe? Manual Medicine 1:2-10, 1995.
- Richardson CA, Jull G, Toppenberg R, Comerford M: Techniques for Active Lumbar Stabilization for Spinal Protection. Australian Journal of Physiotherapy 38:105-112, 1992.
- Robinson R: The New Back School Prescription; Stabilization Training. Part I. Occupational Medicine 7:17-31, 1992.
- Saal JA: The New Back School Prescription: Stabilization Training Part II. Occup Med 7:33-42.
- Saal JA: Nonoperative Treatment of Herniated Disc: An Outcome Study. Spine 14:431-437, 1989.
- Sahrmann S: Posture and Muscle Imbalance: Faulty Lumbo-Pelvic Alignment and Associated Musculolskeletal Pain Syndromes: Orthop Div Rev- Can Phys Ther 12:13-20, 1992.
- Sahrmann S: Diagnosis and Treatment of Muscle Imbalances and Musculoskeletal Pain Syndrome. Continuing Education Course. St. Louis, 1997.
- Strohl K, Mead J, Banzett R, Loring S, Kosch P: Regional Differences in Abominal Activity During Various Maneuvers in Humans. Journal of Applied Physiology 51:1471-1476, 1981.
- Stokes M, Young A: The Vontribution of Reflex Inhibition to Arthrogenous Muscle Weakness. Clin Sci 67:7-14, 1984.
- Tesh KM, ShawDunn J, Evans JH: The Abdominal Muscles and Vertebral Stability. Spine 12:501-508, 1987.
- Throstensson A, Ardidson A. Trunk Strength and Low Back Pain. Scand J Rehabil Med 14:69-75, 1982.
- Warmerdam ALA: Arthrokinetic Therapy; Manual Therapy to Improve Muscle and Joint Functioning. Continuing Education Course. Marshfield, WI 1996.
- Wilke HJ, Wolf S, Claes LE: Stability Increase of the Lumbar Spine with Different Muscle Groups: A Biomechanical in Vitro Study. Spine 20:192-198, 1995.