Drivers Beware:
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Traditional Exercises to Correct Standing Posture: Science or Snake Oil?

by Dennis Zacharkow, PT
© 2017


Figure 1. The most common standing posturual fault is a sway back posture. From Checkley, E.: A Natural Method of Physical Training. Brooklyn, William C. Bryant and Co., 1890.

Posture authorities from over a century ago identified the sway back posture as the most common standing postural fault (Checkley, 1890; Lovett, 1902; Skarstrom, 1909; Bancroft, 1913). These and other posture experts (Rathbone, 1934; Howland, 1936; Knudsen, 1947; Schoberth, 1962) described the main characteristics of a sway back standing posture as a swaying forwards of the pelvis and hips, a leaning backwards of the upper trunk, a protruding lower abdomen, a depressed chest, round shoulders, and a forward head posture (Figure 1). Kellogg (1927) and Hawley (1937) found the sway back standing posture most frequently in sedentary individuals.

(Author's note: All of the individuals cited above were true posture experts. They should not be grouped with today's self-proclaimed posture experts on the internet, especially YouTube, who are mainly experts at promoting posture misinformation.)

Traditional Approach to Correcting a Sway Back Standing Posture

Based on the belief that a sway back standing posture is caused by muscle weakness and muscle imbalances, traditional physical therapy treatment for correcting a sway back posture mainly involves segmental strengthening exercises. For example, various abdominal exercises are prescribed to realign the pelvis and spine, and scapular retraction exercises are prescribed to correct round shoulders. The major problem with this approach is that major physical therapy studies do not support the prescription of segmental exercises to improve posture.

Regarding abdominal muscle strengthening, results from Walker et al. (1987) indicated that lumbar lordosis, pelvic tilt, and abdominal muscle function during normal standing are not related. Youdas et al. (1996) found no correlation between the angle of pelvic inclination and the depth of lumbar lordosis in standing posture. They concluded that "the use of abdominal muscle strengthening exercises … to correct faulty standing posture should be questioned."

Regarding scapular retraction exercises, DiVeta et al. (1990) found no relationship to exist between the position of the scapulae in standing subjects and the muscle force produced by the middle trapezius. They concluded that clinical practices such as using middle trapezius strengthening exercises to correct a round shoulder posture need to be re-examined.

Postural Stability and Energy Expenditure

In contrast to the muscle weakness/muscle imbalance approach, a more scientific explanation for why the sway back posture is the most common postural fault involves understanding the concepts of postural stability and energy expenditure.

Hellebrandt and Franseen (1943) commented that in standing posture the "architectural design of the human body is not conducive to stability. A segmented structure, its center of gravity is placed high above a relatively small supporting base."

Standing postural behavior can be interpreted as spontaneous attempts at attaining relative stability of the body's segmented structure (Branton, 1969). Through the introduction of passive mechanisms, postural stability can be increased, and total muscular effort can be reduced to a minimum, thereby minimizing one's energy expenditure (Nubar and Contini, 1961; Schoberth, 1962).

In the sway back standing posture, this passive mechanism to increase stability and reduce energy expenditure starts at the hip joints.

In idealized erect standing posture, the hip joints are not in maximum extension. Radiographic investigations by Åkerblom (1948) on twenty-five subjects showed that the amount of further hip extension possible from erect standing may be as much as 15 degrees, with the average being 6 degrees.

In normal standing posture, Åkerblom (1948) considered the trunk to be balanced over the hip joints in a position of unstable equilibrium, with the line of gravity usually falling just posterior to the center of the hip joint.

In the sway back standing posture, one tilts the pelvis backwards and fully extends the hip joints (Braus, 1921; Brunnstrom, 1972). The hip joints are then passively stabilized in extension by tension of the iliofemoral ligaments.

Stabilization of the hip in full extension through tension of the iliofemoral ligament can also increase knee stabilization in extension. According to Meyer's theory (1853), as explained by Brunnstrom (1972):

"... in complete hip extension when the iliofemoral ligament becomes tensed, this ligament causes the femur to internally rotate with respect to the pelvis (and with respect to the tibia). This internal rotation of the femur at the knee constitutes a locking mechanism, since the shape of the femoral condyle is such that flexion can take place only if the femur first externally rotates somewhat with respect to the tibia. Meyer furthermore points out that stability of the knee is also affected by the iliotibial tract which is attached to the anterior surface of the lateral condyle of the tibia. As the hip extends fully, the iliotibial tract is put on a stretch and this stabilizes the knee against flexion."

In addition, passive stabilization of the hip and knee due to tension of the iliofemoral ligament can also contribute to stabilization at the ankle joint. [See Luciani (1915) for details.]

McCormick's (1942) investigation of the metabolic cost of standing posture verified that due to the above described passive mechanisms, the sway back standing posture is the body alignment associated with the least energy expenditure.

The New Science for Correcting a Sway Back Standing Posture

In the sway back standing posture, with the hips thrust forward in full extension and the upper trunk leaning backwards, the elongation reflex of the body is inhibited (Haynes, 1928; Rathbone, 1934). Therefore, the key to correcting a sway back standing posture is patterning the neuromuscular system in an elongated movement pattern for several hours a day. This is most effectively accomplished with one's driving posture and sitting posture, and not one's standing posture.

Compared to standing, sitting is more conducive to stability. In sitting, not only is the center of gravity of the trunk lowered, but the base of support is enlarged, extending from the feet to the buttocks (Asatekin, 1975; Carlsöö, 1972). If the energy expenditure when lying down is taken as 100 percent, standing will result in an 8 to 10 percent increase in energy expenditure. Sitting, however, will only result in a 3 to 5 percent increase in energy expenditure (Grandjean, 1973).

The two primary Posture Activators™ for eliciting an elongated posture when driving and sitting are sacral support and lower thoracic support.

Sacral Support (Figure 2)

Maintaining gentle pressure against the sacral support will counteract the forward migration of the pelvis and hips, characteristic of both slumped sitting postures and sway back standing postures. Sacral support will also promote activation of the deep lower abdominals, resulting in a raised position of the diaphragm, along with greater depth and expansion of the lower rib cage.

Preventing the pelvis and hips from migrating forward when driving and sitting is further enhanced with a slight backward slope to the seat of approximately 5 degrees (Zacharkow, 2013). Forward-sloping seats with the hips higher than the knees will actually inhibit the body's elongation reflex by increasing the forward sliding force, and the forward migration of the pelvis and hips on the seat (Zacharkow, 2013). So, a slight backward-sloping seat is an important secondary Posture Activator. Forward-sloping seats are Posture Inhibitors™.

When driving, a fixed inclined footrest for the left foot, also called a dead pedal, is an important secondary Posture Activator to counteract the forward sliding force on the seat (Zacharkow, 1988).

Lower Thoracic Support (Figure 3)

Besides sacral support, lower thoracic support is the other primary Posture Activator when driving and sitting. By stabilizing the rib cage in an elevated posture, lower thoracic support elongates the thoracic spine. Lower thoracic support at T10-T12 (not lumbar support, mid-thoracic support, or upper thoracic support), is the key spinal region for correcting the leaning backwards of the upper trunk. Lumbar support, mid-thoracic support, and upper thoracic support are all Posture Inhibitors (Zacharkow 2015a, 2015b).

An important secondary Posture Activator for elongated sitting is an inclined work surface. With the typical horizontal work surface, an elongated posture of the head/neck/upper back is inhibited (Zacharkow, 1988).

Depending on how much driving and sitting is done by the individual, the Posture Activators of sacral support and lower thoracic support are patterning the neuromuscular system in an elongated trunk posture for at least several hours a day. Traditional exercises, by lasting only a few minutes a day, have no lasting effect on the neuromuscular system.

Standing Movement Patterns

Hours of elongated driving and sitting each day naturally carry over into a elongated trunk posture when standing. The proper movement patterns at the ankles, hips, and arms when standing are the final steps in correcting the sway back posture.


Figure 4. Hip and ankle movement pattern.

Hip and Ankle Movement Pattern (Figure 4)

Swaying backwards from the ankles, while elongating the thoracic spine and elevating the rib cage, is the most effective standing movement pattern for correcting a sway back posture (Alexander, 1918).

Stand with one foot placed a very short step forward in advance of the other foot, with the arms held in approximately 135 degrees of shoulder flexion. Sway backward from the ankles until the body weight is over the middle of the rear foot. The backward swaying will start at the ankles, but will also result in a backward movement of the hips and pelvis. Concentrate on holding the hips and pelvis back, but do not allow the trunk to bend forward.

Then, lower the arms to the sides with the palms facing posteriorly and the elbows turned slightly outwards. (This arm posture will be explained in more detail in the next section.)

By activating the elongation reflex of the body, this exercise will help obtain the proper axial relationship of the thorax and pelvis, elongate the thoracic spine, and promote a retraction of the lower abdominal wall (Alexander, 1918; Zacharkow, 1988). This exercise is most effective if done barefoot or wearing shoes without heels.

Arm Movement Pattern

Forget about pulling the shoulder blades back and down! This movement pattern actually inhibits an elongated standing posture. It typically results in a hyperlordotic standing posture with forward hips and backward shoulders, and excessive contraction of the scapular retractors (Checkley, 1890; Taylor, 1901; King, 1932).

The typical arm posture when standing involves having the palms facing towards the sides of the body, the elbows pointing posteriorly, and the thumbs facing forwards. However, a little-known arm posture movement pattern will more effectively facilitate the proper positioning of the shoulder blades, chest, and thoracic spine.

This different arm posture, as advocated by Alexander (1918), is as follows: The upper arms should be rotated slightly inwards, with the elbows turned slightly outwards and away from the body. The palms should be facing posteriorly, and the thumbs should be facing the sides of the body. Such an arm posture promotes the proper positioning of the scapulae, which should lie "flat and widened across the back of the properly expanded chest" (Barlow, 1980).

Pregnancy: The Exception to Standing Postural Correction

As pregnancy progresses, with enlargement of the uterus and the increased weight of the fetus, a sway back standing posture is both the normal way and also the safest way to achieve postural stabilization.

Fries and Hellebrandt (1943) found that with the increase in the anteriorly placed load as pregnancy progresses, the pregnant woman compensates by leaning backward beyond her normal gravitational center. This backward displacement of the center of gravity protects against "an acute unbalancing force which might lead to a forward fall, endangering the fetus" (Fries and Hellebrandt, 1943).

There will be a decreased energy expenditure with the sway back postural adaptations as pregnancy progresses, compared to the strong static contraction of the erector spinae that would be required if an excessive lumbar lordosis was the posture adopted to prevent the pregnant woman from falling forwards.

The most important adaptation for achieving postural stabilzation with pregnancy is tilting the pelvis backwards and fully extending the hip joints (Braus, 1921; Brunnstrom, 1972). Without the postural adaptation of full hip extension, the additional anterior load of pregnancy would impose a large, additional spinal load on the pregnant woman.

This additional spinal load of pregnancy, if not compensated for by full hip extension, would be approximately equivalent to the spinal load imposed on a non-pregnant woman, who carried her trunk continuously flexed forward 22.3 degrees from upright (Ostgaard et al., 1993).

During pregnancy, correcting a sway back standing posture is contraindicated. Postural re-education should focus on an elongated sitting posture with the posture activators of sacral and lower thoracic support.

Post partum, the standing movement patterns discussed earlier for correcting a sway back posture can be safely initiated.

Standing at the Computer: A Note of Caution

Unless one is fully aware of their standing alignment at all times, there will always be a tendency to sway the hips and pelvis forward for increased postural stability.

This is the main reason why I disagree with the use of a standing desk for computer work. I have never seen anyone maintain an ideal standing posture at the computer for more than a few minutes. This is because once the individual starts to focus on his/her computer work, postural stabilization is relegated to the subconscious, and stability is increased by swaying the hips and pelvis forward. For this reason, I believe that prolonged standing at the computer can ruin your posture and increase your risk for back pain! Elongated sitting at the computer with the Posture Activators of sacral and lower thoracic support is by far the healthiest computer posture.

References

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