Exercise may be the best medicine for chronic pain

Chronic pain is often hidden from the USA's front pages and TV screens, but it is Americans' biggest health problem. Typically defined as pain lasting more than three to six months, it affects 100 million U.S. adults, according to a 2011 report from the National Academy of Sciences' Institute of Medicine. It is the leading reason people go to doctors, and it costs the nation upwards of $635 billion a year — more than cancer, heart disease and diabetes combined.

But many people, including many physicians, are unaware of the growing number of non-narcotic treatments available; chief among these is exercise. Many sufferers are terrified that if they move, they will damage themselves, but nothing could be further from the truth.

"To date, there is no scientific evidence that activity and exercises are harmful," says James Rainville, a spine and rehabilitation specialist at New England Baptist Hospital in Boston.

Exercise also can help prevent chronic pain: For women 65 and older in one 2011 Norwegian study, the prevalence of chronic pain was 21% to 38% lower among exercisers.