What are three types of muscle contractions? What they are called and what muscles are involved?

Expert Answers

An illustration of the letter 'A' in a speech bubbles

There are three types of muscles (skeletal, cardiac, and smooth) but four types of muscle contractions. Here they are along with examples of muscles used:

1. Concentric contractions are contractions that cause the muscle to shorten. The muscle's maximum is always greater than the force generated by the muscle. An example of a concentric contraction is performing a bicep curl using weights.

2. Eccentric contractions are actually muscle lengthening contractions. As the external load on the muscle rises, the muscle can't create any more force so it instead lengthens. These contractions are common in everyday activities like walking. An example of eccentric contractions are the quadriceps extending as the knees flex while walking.

3. Isometric contractions cause the muscle to be held constant instead of shortening or lengthening. An example of an isometric contraction is holding a box of books in front of your body. The biceps are isometrically contracting.

4. Passive stretch is also a muscle contraction where the muscle is being lengthened in a passive state. An example of passive stretch contraction is the hamstring pull that occurs while doing toe touches. 

 

 

 

See eNotes Ad-Free

Start your 48-hour free trial to get access to more than 30,000 additional guides and more than 350,000 Homework Help questions answered by our experts.

Get 48 Hours Free Access
Approved by eNotes Editorial Team