How Are Muscles Classified?

There are a few things that you are required to consider to understand the classification of muscles. They can be classified according to the type they are. They can be smooth, cardiac and skeletal. The classification can also be done on the basis of its function. On this basis you can classify it into two groups; one is called involuntary and the other one is known as voluntary. There is another way to classify muscles and in this classification morphology is  taken into consideration. In accordance with this classification, there are two types of muscles; one is called striated and another one is called non-striated.
 
If you want to know more about the phenomenon of classification, I can suggest a website that can provide you all the information regarding the classification of muscles. The address is www.ucihs.uci.edu. So visit it and get all the information.

Shunt v Spurt Muscles

Shunt muscles have their distal (furthest from the body) attachment a long way from the joint they work over.  When they work they will tend to pull along the line of the distal bone of the joint and compress the joint.  Therefore they are thought of as good stabilising muscles.  Brachioradialis is a good example of a shunt muscle in elbow flexion (bending).

Spurt muscles have their distal attachment close to the joint they work over and so when they work they tend to pull across the line of the distal bone of the joint and cause movement to take place at that joint.  Biceps brachii is a good example of a spurt muscle in elbow flexion.

ukpmc.ac.uk  has a great picture to illustrate this.  If that fails google spurt and shunt muscles and look for the article by Basmajian.

Hope this helps
Steve