This booklet is for people who have back pain, as well as family members, friends, and others who want to find out more about it. The booklet describes causes, diagnosis, and treatments, and research efforts to learn more about it, many of which are supported by the National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS) and other components of the Department of Health and Human Services' National Institutes of Health (NIH). If you have further questions after reading this booklet, you may wish to discuss them with your doctor.

Causes

Doctors have many ideas about what causes low back pain, but no single explanation applies to everyone.

Low back pain may be related to aging of the disk. As a result of wear and tear on the spine, ligaments, and disks, a disk may begin to protrude or collapse and put pressure on the nerve root leading to a leg or foot, causing pain in those areas (sciatica).

Symptoms

Low back pain means a pain or ache somewhere between the bottom of the ribs, at the back, and the top of the legs. The pain often begins suddenly, and may follow an obvious strain or injury, but may seem to come on "out of the blue", or come on slowly.

The pain may travel to or be felt elsewhere. It often goes into the buttocks, but may go further down the leg and even into the foot.

The pain may be worse on bending and is often worse sitting, especially in an easy chair. Sometimes turning over in bed and sitting up are agonising. Coughing or sneezing can often make the pain much worse. The muscles of the back may go into painful spasm.

Back pain may be combined with pain into the leg, travelling down below the knee, this is otherwise known as sciatica, because the main nerve to the leg (the sciatic nerve) is being irritated by pressure on it.

In this section I have been talking about what we term simple or mechanical back pain, which is far and away the most frequent cause of low back pain. There are various other symptoms which may go with back pain, some of which suggest problems other than back problems, and some of which point to the need for more urgent action by you and your doctor.

Aerobic exercise for back pain

Aerobic exercise means performing a physical activity that causes your heart rate to increase enough to make your body use its oxygen supply to burn fats and glucose. The more oxygen used the greater the carbon dioxide produced, meaning that breathing has to become faster to accommodate this demand.

The aim of participating in aerobic exercise of any type is to elevate the heart rate to increase oxygen consumption, and to achieve a level of manageable breathlessness.

There are two types of aerobic exercise, high-impact and low-impact. High-impact is more challenging and is good when a medium level of fitness has already been achieved.

Low-impact is better for beginners and those who have injuries; it is gentler and participants can build-up gradually to be fit enough to undertake high-impact aerobic exercise.