Understanding Sitting Posture

What can happen when we sit poorly

Sit up straight! Don't lean over your plate of food! The request is straightforward, but the 'doing' may well be something else. How can you change something you're not even aware you're doing?

Slouching is a result, not a cause of poor sitting posture.

Slouching effect on our sitting posture can be considered a symptom of a much more serious issue within our body.

Poor sitting habits can lead to slouching as you slump over, reducing the muscles around your spine’s natural alignment and causing all sorts of pains in this area – one that can force your body into a downward direction.

As we search for a ‘natural’ sitting position, we are putting undue pressure on the low back and creating harmful tension throughout the body. The proper sitting position is essential to maintaining a healthy body and mind.

Many people seek the guidance of a posture professional when trying to sit correctly. While a stable sitting position is essential to maintaining a healthy body and mind, this may not always be possible. It’s just as important to remember this when seeking advice.

The effects of slouching on your posture

Girl sitting on books

It has been said that slouching can be a way to achieve a balance in the distribution of stress, pressure, and support from the body. During sitting, you use the same muscles to support you through many daily activities.

Slouching is the natural response to the force of gravity in all natural beings. You may not believe it, but gravity is a mighty force, even more substantial in humans than we realize.

Humans are naturally sensitive to gravity and, during the day, this sensitivity can be intensified. This is why when you stand up from a sofa, you are likely to feel a difference as you begin to walk around. It may feel like your legs are longer than they really are, and your hip joints will feel heavier than usual.

Spend enough time in a chair, and you will run the real challenge of slouching or collapsing your body moves in a downward direction:
 
  • You may struggle with the position of the pelvis.
  • The lower back can lose its natural curve, causing a flattening or reverse curve of the lumbar spine.
  • The chest/rib cage begins to collapse (once again succumbing to the ever-present effects of gravity.
  • Add to this the head and neck beginning to move too far forward.
  • Also, the Rib cage attaches to the thoracic spine. Therefore If while sitting poorly, the rib cage collapses, then by virtue of its attachments, the Thoracic spine will also change its position. As the rib cage moves forward and down, the thoracic spine will curve more than its design allows. Potentially leading to excessive Thoracic Kyphosis.
  • A funny thing happens when the head and neck follow the chest downwards. Our internal self-correcting system will tilt the head once again in the opposite direction. Can you see how this will create undue stress and strain on the neck and shoulders as the natural curve of the spine at the neck is challenged to increase its curve excessively? Potentially leading to Forward Head Posture.

Our brain in its wisdom to protect and keep us moving forward wants us to look ahead so we can keep a-head.

Further Sitting Posture Considerations

A study completed by Dolan and Green in 2006 required subjects to:

  • Sit in a slouched position for 3 seconds and then find a neutral sitting position for the spine, and then to,
  • Sit in a slouched position for 300 seconds and then find a neutral spine

The study found a direct relationship between prolonged periods of sitting in a ‘slouched’ position and a later increased difficulty in finding a comfortable neutral sitting position.

Further studies have found that sitting on chairs that encourage the lower back to round out backwards into a lumbar kyphosis (a movement away from a natural curve may) can directly affect the health and well-being of spinal discs.

This is because spinal discs offer a ‘cushioning’ between the vertebrae (Intervertebral Discs). As a result, the changes can potentially lead to a lack of support, stability, and lower back pain.

We, therefore, need to assess:

  • How we sit;
  • How long we spend in uninterrupted sitting;
  • What measures we have (or should) put into place to get up and move if we ‘must’ sit for extended periods.
References
  • Dolan, K.J., & Green, A. (2006). Lumbar spine repositioning sense: The effect of a ‘slouched’ posture. Manual Therapy. 11(2006) 202-207.
  • Kendall, F.P., McCreary, E.K., & Provanc, P.G. (1993). Muscles, testing and function (4th ed). Baltimore, MD: Williams & Wilkins.
  • Pynt, J., Mackey, M.G., & Higgs, J. (2008). Kyphosed seated postures: Extending concepts of postural health beyond the office
POSTURE CONSIDERATIONS