Intense back pain, especially in the lower back, is a big problem that most people will experience at least once at some time in their lives. The muscles that support the lower back and spine constantly used; even while simply sitting, the muscles are in use to keep one from falling over. The spine also bends, straightens and twists. This constant stress on the back can result in back strain and pain.
The lower back supports most of the weight of the body and is subject to the most mechanical stress. As a result, the lower back is commonly injured. Lower back pain caused by strained muscles or ligaments is the most common type of back pain.