07 Mar Kinetic Chain Dysfunctions in Sport
The kinetic chain of the human body is comprised of the articular, muscular, and nervous systems. It is these three sub-systems of the kinetic working interdependently to create efficient movement within the human body. Relative to the athlete in competition, these three sub-systems cohesively function together to run, throw, hit, swing, jump, and change direction. Unfortunately, dysfunction in one of these systems or a combination of systems will deter from performance during competition, lead to the development of inefficient movement patterns, and create a cycle of injury.
Dysfunctional movement patterns within the human body are a result of impairments within these systems of the kinetic chain. Breakdowns within the articular, neural, and muscular system results in Serial Distortion Patterns. A serial distortion pattern refers to the situation where the integrity of the kinetic chain is compromised because of dysfunction within one of the components within the kinetic chain. This results in a decrease in functional efficiency within kinetic chain relative to the movements an athlete will execute during sport.
Two of the most common serial distortion patterns found in the kinetic chain are the lower cross syndrome, and upper cross syndrome. Both the lower cross syndrome and upper cross syndrome were first noted by physical therapist Vladimir Janda of the Czech Republic. Janda noted through research two distinct distortion patterns of muscles imbalances develop within the kinetic chain due to poor postures.
Lower Cross Syndrome and Upper Cross Syndrome
Janda noted when muscles of the kinetic chain are shortened or contracted for an extended period of time reciprocal inhibition occurs. Reciprocal Inhibition is the state in which over activity in a specific muscle creates a decreased functioning of the muscle’s antagonist. As a result the antagonist becomes inhibited in terms of functioning properly during human movement. This results in muscular imbalances, synergistic dominance, and poor movement patterns.
Janda, during his research, noted Lower Cross Syndrome is the state in which an individual will have an anterior tilt of the pelvis in conjunction with increased lumbar extension. Lower cross syndrome will typically include a group of muscles that are tight and a corresponding set of muscles that are weak. Muscles within lower cross syndrome found to be tight are the gastroc, soleus, iliopsoas (hip flexors), adductors complex, quadriceps complex, hamstring complex, erector spinae (lower/mid-back), tensor fascia lata (TFL), and quadratus lumborum (QL). Lower cross syndrome will in addition find the following muscles/muscle groups to be weak with low neural outputs: rectus abdominus, multifidus, gluteus maximus, gliteus minimus, gluteus medius, latimus dorsi, transverse abdominus, and internal obliques.
The coinciding pattern of tight muscles and weak or inhibited muscles creates dysfunctional movement patterns within the kinetic chain. Common dysfunctions associated with lower cross syndrome are poor stabilization of the lumbar spine, over-active hamstring complex, decreased neural drive within the glutes, altered hip extension, and articular stress within the SI joint and facets of the lumbar spine. (Michael Clark, Director, National Academy of Sports Medicine)
Lower Cross Syndrome
Upper Cross Syndrome, also noted by Janda, is the state in which an individual is characterized by an anterior rounding of the shoulders with a forward extension of the head. This is again caused by reciprocal inhibition, where a specific group of muscles are tight and a corresponding set of muscles that are weak.Muscles within upper cross syndrome found to be tight are the pectoralis major, pectoralis minor, levator scapula, upper trapezius, sternocleidomastoid, scalenes, and suboccipitals.Muscles found in upper cross syndrome to be weak and having low neural outputs are the lower and mid trapezius, serratus anterior, teres minor, serratus anterior, and infraspinatus.
Similar to lower cross syndrome, upper cross syndrome creates a common series of dysfunctions associated with it. Poor thoracic spine extension and limited spine rotation are common dysfunctions associated with upper cross syndrome. Injuries such as rotator cuff impingement, gleno-humeral instability, and thoracic outlet syndrome are commonly associated with upper cross syndrome.
Upper Cross Syndrome
Both the lower cross and upper cross syndromes create numerous kinetic chain dysfunctions resulting in poor movement patterns directly affecting the biomechanics of the movement patterns associated with throwing, hitting, swinging, and sprinting. In addition the structural integrity that is compromised by both the lower and upper cross syndrome increases the potential for injury exponentially increases.
Reciprocal inhibition is the decreased neural drive or force production in a functional antagonist caused by a tight muscle on the opposite side of a joint.
Synergistic dominance is the process by which a stabilizer, neutralizer, or synergist takes over functioning of an inhibited prime mover causing over use syndrome within the stabilizer, neutralizer, or stabilizing muscle.
Arthokinetic inhibition is the inhibition within muscular system caused by dysfunction within a joint of the articular system. This results in limited ranges of motion and dysfunctional movement patterns.
Over Active Musculature
Dysfunction within the kinetic chain where a muscle(s) is recruited improperly relative to optimal firing patterns within the kinetic chain. Resulting in potential overuse of the specified muscle(s), inhibition of the muscles antagonist, poor motor control, and improper functional movement patterns.
Under Active Musculature
Kinetic chain dysfunction where a muscle’s firing rate is at a level considered “below normal” for the functional movement pattern of the kinetic chain. Resulting in decreased motor control, stabilization, and force outputs from the kinetic chain.
Relative flexibility is the process by which the human body seeks the least amount of resistance during functional movement patterns. Relative flexibility is typically a result of muscular imbalances within the kinetic chain causing altered length tension relationships.
Cumulative Injury Cycle
A cumulative injury cycle is a cycle of continuing dysfunction within the kinetic chain in the form altered length tension relationships, muscles imbalances, over active musculature, under active muscular, or articular deformation as a result of injury.
Cumulative Injury Cycle
Efficient human movement and execution of the athletic actions requires mobility, flexibility, functional strength, stability, and power development within the entire kinetic chain. This allows for the production and reduction of force to coordinate functional movement patterns in associated with throwing, hitting, swinging, sprinting, and changes of direction. A lack of mobility, flexibility, stability, strength, or power within the muscular system can significantly inhibit the ability of the kinetic chain to operate efficiently thus creating inefficient movement patterns. This leads to compensation patterns, which in turn over stresses certain muscular structures and joints leading to the development of a cumulative injury cycle. The athlete, medical professional, and coach should be very cognitive of existing kinetic chain dysfunctions existing within their athletes. These types of situations will adversely affect the execution of efficient movements patterns in sport.
In addition, the process of correcting physical dysfunction through corrective exercise strategies in addition to the development of greater efficiency within the movements patterns of the athlete can drastically reduce the potential for sports related injuries. The process of correcting physical dysfunction begins with assessment of the kinetic. The second step is the implementation of corrective exercises programming. Through these processes a physical foundation can be developed to execute the efficient movement patterns, decrease kinetic chain dysfunctions, and avoid the cumulative injury cycle.
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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