They constrict, cramp, & spasm in an attempt to prevent losing body heat.
The muscles will atrophy (shrink) if not used.
Yes it loosens up muscles and prevents them from tearing. Cold, stiff muscles tear much easier.
A cold compress is good for swollen tissues. For tired muscles the best thing is heat or massage.
They contract
you excersise
The common pitfall one faces in answering this question is to read too much into it! The question does not imply that the body's muscles are regulating the body's temperature as the circulatory system does: 24 and 7. Instead, simply think of what happens on those rare occasions when you are very cold. What happens? You shiver, sometimes violently. What's causing the shivering? Your body's muscles. End of story.
what effect the muscles are the cold water
you will die
you exhale (:
contrast
When you are cold, your muscles contract (become tighter) quickly to warm you up. This is called shivering. Your teeth chatter as your muscles in your jaw move. [Just to clarify: MY teeth do not chatter when YOU are cold]
When you get cold and shiver, your muscles contract and relax rapidly to generate heat and warm up your body. This process helps maintain your body temperature.