Why is good posture so important?!

Why is good posture so important?

I have to do a report on good posture but i need to know why bad posture is bad and what the effects (short term and long term) are.

Our bodies were disigned to work within certain parameters with certain biomechanical relationships. There are optimal positions for every task we do and the most mechanically advantaged position usually starts with good posture at the spine.

Your spine has normal "curves"...a "lordotic" or "inward" curve at the neck and low back (cervical and lumbar spine) and a kyphotic curve at the thorasic spine and sacral area. Maintaining these curves allow for proper force distribution and mechanical advantage of muscles during our daily lives. It also maintains the vertebral disc (which acts as a shock absorber and facilitator of movement) in a neutral postion. Assuming bad posture can have undesireable consequences on these structures.

First, let's take a look at short term effects. Sit on the edge of your chair and slouch to your maximum (reduced lumbar lordosis, increased thorasic kyphosis and a "forward head posture"). As ligaments and muscles are stretched at end range, they will eventully become painful. Mechanoreceptors (nerves that sense change in forces) are activated, telling you that your body does not want to be in that position for too long. Furthermore, our thorasic cavity also becomes smaller in this position...this leaves less room for lung expansion. Finally, the biomechanical effects are immediate...notice that from a the slouched position that you cannot reach as high with your arm as when you are using good posture. Poor posture is often the root cause for many people with shoulder problems.

Most of us will change position before any detrimental effects of bad posture occur, but repeated poor posture can have long term effects as well. Probably the most significant long term effect is a displacement of the nuclear material (a jelly like substance) in the middle of a vertebral disc. With poor posture, it usually creeps backwards, which can make the disc bulge or herniate. This can cause back pain, or if severe enough, can begin to pinch a nerve (which are positioned behind the disc). This usually causes pain down the leg...commonly known as sciatica. Once this has occured, it is more likely to occur again. Back pain remains one of the most costly conditions to the healthcare system. Most of which can be prevented, in my opinion.

Adopting good postural habits in youth, can be a good way to become accustomed to them by adulthood. Posture while seated is especially important since this put a high grade of pressure on the disc. As more and more jobs require prolonged seated positioning, it is especially important to learn good posture and include good postural habits such as regular exercise and refraining from sitting from longer than 30 minutes.