Causes and effects about having stiff shoulder (Outline)

Having stiff shoulder caused by the following factors: unnatural position, feeling cold, and psychological problems.

1.First of all, unnatural position effects having stiff shoulder since keeping unnatural position makes shoulder’s muscles tense.
For examples,

People who do deskwork with a stoop or their legs crossed have stiff shoulder easily.
Also, people who use pillows which are too tall and soft for long time have stiff shoulder easily.

As a result, unnatural position causes shoulder’s muscles heavy task, and then effects having stiff shoulder.

2. Secondly, feeling cold effects having stiff shoulder since unconsciously shoulder’s muscle could be contract easily.
For example,

People who rarely exercise in winter season have stiff shoulder easily.
In another case, it is easy to be unnatural position.

As a consequence, contraction of shoulder’s muscle cause muscle’s blood circulation, and effect having stiff shoulder.

3.Finally, psychological problem effects having stiff shoulder since stress makes muscle’s blood vessel contract.
For examples,

People who remain unstable and strain have stiff shoulder easily.
Additionally, perfectionist is easy to have stiff shoulder.

In short, stress also cause muscle’s blood circulation, and effects having stiff shoulders.

On the whole, having stiff shoulder is related to task for shoulder’s muscles and muscle’s blood circulation. Those are caused by unnatural position, feeling cold, and psychological problems.