The most common cause of lower back pain is fatiguing of the muscles that run along the sides of the spinal column, called the paraspinal muscles. This is very common in people who work on their feet all day and in those who have to do a lot of lifting and carrying.
The best solution to this kind of low level back pain is conditioning. Performing daily exercises to improve the flexibility and strength of these muscles can prevent the discomfort. Your primary care doctor
should be able to give you a list of back strengthening exercises, or you may be able to find them on the internet as well.
Occasionally, the fatigue can become so much that the muscles actually cramp up, causing a paraspinal muscle spasm. This can be treated with rest and stretching and anti-inflammatory medicines like ibuprofen; sometimes anti-spasms medications are necessary also and can be prescribed by your doctor.
Most low back pain is not medically serious. However, if you have numbness or tingling
in the legs or weakness in the legs or any problems with bowel or bladder control these could be signs of a more serious problem, and you should talk to your doctor as soon as possible