Take a look around your office, cubicle prisoners hunched over their keyboard like a tyrannosaurus rex devouring their prey, Lexus pushing executives sprawling all over their mahogany desks and kicking back and lounging on their leather presidential chairs and people slumping around with shoulders so internally rotated it looks as if their head is sitting upon a wooden upscale department store hanger. Over time, prolonged horrid static posture and inactivity wreak havoc on the body, both physiologically and orthopedically.
A common issue facing many of these 9-5ers or workplace “athletes” is excessive lordosis, also referred to as swayback. Swayback rears its ugly head when a person sits in flexion for long periods. Sitting for long durations causes the hip flexor muscles (iliopsoas and rectus femoris) to be overactive and tight.
Flexion is the primary function of the iliopsoas, which is comprised of two muscles, the illiacus, which originates on the pelvic crest and attaches to the femur and the Psoas Major, which originates on the lumbar spine and also attaches to the femur. Inadequate functioning of the psoas leads to flexion based back pain (it should be noted that the psoas is the sole active hip flexor above 90 degrees of hip flexion).
The rectus femoris, which also is one of the four quadriceps muscles, is dually responsible for the functions of hip flexion and knee extension. Excessive activity of these muscles usually indicates weakness of the gluteal muscles (gluteus maximus, gluteus medius, and gluteus minimus), medial and lateral aspects of the hamstrings, abdominals, obliques, and erector spinae.
Some curve in the back is good. A natural lordotic curve is completely normal and healthy for the lumbar regions of the spine. Because of this fact, the idea of a straight back is inaccurate. Lordotic curves of both the lumbar and cervical spine serve to distribute stress on the spine and act as shock absorbers. However, the each region of the spine should remain in its natural curve, or neutral in static posture and dynamic movements while supported by surrounding balanced musculature (McGill, 2004).
If any imbalances exist, the spine, specifically, could slip into extension or flexion. Patients with lumbar lordosis can also have pain because of extension of the lumbar spine (Sahrmann, 2002). Extension based back pain is exacerbated by prolonged periods of standing and those suffering from it will have short hip flexors, weak glutes, and lack anterior core stability.
We can determine from these findings that excessive lumbar flexion and lumbar extension are detrimental to posture, spine health, performance, and hip mobility. It should be noted that many cases of lordosis are asymptomatic and a degree of lordosis is actually normal. Lumbar lordosis at 45 degrees is considered healthy (Neumann, 2002). We can conclude from this, that a neutral spine is a “normal” spine.
See Figure 1 for a comparison of the features between an excessively lordotic lumbar spine and a neutral spine.
|Excessively Lordotic Lumbar Spine||Normal Spine|
|Excessive inward curve of spine||Slight lordotic curve exhibited|
|Lordosis exceeding 45 degrees||Lordosis at 45 degrees – neutral|
|Anterior Pelvic Tilt||Neutral pelvis (not anterior nor posterior)|
|Protruding Buttocks||Stronger, activated glutes|
|Caused by disease, inactivity, prolonged poor posture and obesity||Achieved through physical activity, proper posture, strong core muscles, keeping normal weight|
Vertebrates rely on the healthy functioning of the spine to deliver major body and limb movement. We know that a healthy spine is integral to movements ranging from complex rotational movements down to simple movements such as gait.
However, muscular subsystems, or groups of muscles working synergistically, are integral in human movement and stabilization. These subsystems include the deep longitudinal subsystem, the lateral subsystem, the posterior oblique subsystem, and the anterior oblique subsystem.
The deep longitudinal subsystem is comprised of the tibialis anterior, peroneus, longus, lateral aspect of the hamstrings (biceps femoris), sacrotuberous ligament, thoracolumbar fascia, the erector spinae group. These muscles are largely involved in stabilization, which is the main function of the deep longitudinal system.
In addition to stabilization, the subsystem absorbs and transfers ground force; decelerate forward leg movement and resisting trunk flexion, by stabilizing the spine (Aaberg, 2006). For instance when walking, running, or performing a lunge movement, the hamstrings serve as the synergist in decelerating forward leg movement or hip flexion and knee extension.
In addition to serving as a synergist in deceleration, the hamstrings also fire eccentrically in hip extension (deadlift, glute ham raise) and knee flexion movements (prone leg curl). Activating the biceps femoris increases tension in the sacrotuberous ligaments, transferring force across the sacrum, stabilizing the SI joint, permitting force transference through the spinal erectors to stabilize the trunk (Aaberg, 2006).
Next up is the lateral subsystem and its components, which include: the gluteus medius, tensor fascia latae, quadratus lumborum, and the adductors. The muscles of lateral subsystem are called upon when moving in the coronal or frontal plane. The lateral subsystem is most involved in pelvic and spinal stabilization during single-leg impact (Aaberg, 2006).
The action of powering off the planted and recently impacted leg helps balance the body’s shifted center of gravity and optimal positioning needed for the succeeding impact of the opposite leg (Aaberg, 2006). The synergists in this are the hip adductors which work with the opposite-side lateral flexors of the trunk to stabilize the pelvic girdle and slightly raise the opposite leg (Aaberg, 2006).
Posterior oblique subsystem is composed of: the gluteus maximus, thoracolumbar fascia and it’s relation to the latissimus dorsi. The system operates obliquely, for instance during the gait cycle, the latissimus dorsi and gluteus maximus, both extensors, simultaneously extend the opposite arm and opposite leg during the gate cycle. This system is relied upon heavily in transverse or horizontal plane movements through rotational activities such as throwing a ball, discuss, and swinging a golf club or baseball bat.
The anterior oblique subsystems functions mirror those of the posterior oblique subsystem as it also functions contralaterally. The internal and external oblique muscles as well as the adductor complex and hip external rotator complex make up the subsystem. This collection of muscles proves instrumental in pelvic stability and rotation. Rotation as we know is needed to generate a swinging motion for the legs. For a breakdown of each subsystem’s characteristics, refer to Figure 2.
|Deep Longitudinal Subsystem||Lateral Subsystem||Posterior Oblique Subsystem||Anterior Oblique Subsytstem|
|Muscles Involved||Erector Spinae
Tensor Fascia Latae
Hip External Rotator Complex
|Primary Functions||Sacroiliac Joint Stability
Force transference throughout kinetic chain
|Pelvo Femoral Stability||Sacroilliac Joint Stability
|Sacroilliac Joint Stability
|Plane of Movement||Sagittal||Coronal||Sagittal to Transverse||Transverse|
Combating poor posture is difficult, even more difficult is correcting and addressing imbalances in static posture. Identifying and correcting issues during dynamic posture (or movement) is an even more daunting task, especially if the subject exhibits static posture issues. Faulty loading and movement patterns are developed as your body in one way or another, attempts to compensate for weaknesses. That’s why it’s of the utmost importance to make sure there are no weak links in your kinetic chain.
Soldering these weak links can be addressed by strengthening the joint support system, which consists of the musculature and connective tissue (ligaments and tendons) that surround the structures needed for movement. For instance, the vastus medialis, which obliquely rests atop the knee joint, is crucial in knee stability.
The lower fibers of the trapezius and the serratus anterior are needed to stabilize the scapulae during an assortment of movements. Strengthening your abdominals, obliques, and spinal erectors will help stabilize your spine. Balance distributed among the four small, often neglected and injured muscles comprising the rotator cuff (teres minor, supraspinatus, infraspinatus, subscapularis) will make a world of difference in terms of shoulder health.
More often than not, we identify the problems a bit too late, addressing the problems after the 11th hour has already passed, leaving the client’s fate lying in the hands of an orthopedic surgeon, literally.
In swayback, functioning of the joint support system, including each of the muscular subsystems is compromised. Kinetic chain imbalances can be attributed to a bevy of things, namely postural stress. These postural dysfunctions can be staved off through interventions such as teaching proper static posture and dynamic postural alignment, but for someone with swayback this becomes tricky.
The hamstrings of the deep longitudinal system are affected in swayback due to the forward tilt of the pelvis, causing the syngergistic dominance of the hip flexors and musculature of the lower back. In swayback, the pelvis rests upon the anterior ligaments of the hip, rather than balance muscles for support causing the musculature of the upper back, including the erector spinae group and latismuss dorsi of the posterior oblique subsystem, to sway backwards to offset the anterior pelvic tilt. Syngergistic dominance now sets in the erector spinae of the cervical spine region, trapezius 1, and rhomboids, limiting the range of cervical and lateral flexion.
The quadratus lumborum and erector spinae of deep longitudinal and lateral subsystems, respectively, become tight, overcompensating for weak abdominals which are needed for spinal stabilization. The inward curve of the spine and anterior tilt of the pelvis leads to medially rotated femurs, negating the effective functioning of the adductor complex and hip external rotator complex of the anterior oblique subsystem. Internally rotated hips cause a plethora of knee and ankle and excessive foot pronation.
Further up the chain, spinal shearing on the lumbar disks may occur. Tightness in the thoracic region will lead to an increased movement load on the lumbar spine, and locally may cause thoracic disc injuries and costovertebral joint strains. The domino effect of all of these issues throws off the force-couple relationship of the entire body!
In conclusion, after taking all of these factors into consideration, we must first address static postural imbalances before addressing issues through movement and concentrating on enhancing performance.
What do you think?
Joe Giandonato, MS, CSCS, is a Philadelphia-area healthcare support professional and personal trainer, he holds an M.S. in Exercise Science and has nearly a decade of personal training experience. Presently, he is employed as a Fitness Specialist with the University of Pennsylvania, Department of Recreation and also trains clients Broad Street Fitness in Philadelphia, PA. He is also pursuing a MBA with a concentration in Healthcare Administration, is a Certified Strength and Conditioning Specialist (CSCS) through the National Strength and Conditioning Association and a Performance Enhancement Specialist (PES) through the National Academy of Sports Medicine. More of his articles can be found on elitefts.com, joshstrength.com, beyondstrengthperformance.com, and personaltrainersunited.com.