Exercise no danger for joints

There is no good evidence supporting a harmful effect of exercise on joints in the setting of normal joints and regular exercise, according to a review of studies published in this month's issue of the Journal of Anatomy.

Exercise is an extremely popular leisure-time activity in many countries throughout the Western world and has for many become part of the modern lifestyle. It is widely promoted in as being beneficial for weight control, disease management in cardiovascular disease and diabetes, and for improving psychological well-being amongst an array of other benefits. In contrast, however, the lay press and community perception is also that exercise is potentially deleterious to one's joints, in particular those of the lower extremities.

Researchers from Boston, USA, and Ainring, Germany, reviewed existing studies on the relationship between regular exercise and osteoarthritis (OA) and concluded that in the absence of existing joint injury there is no increased risk of OA from exercise.

"We found that in elite athletes where there was more likelihood of obtaining sports injuries, there was an increased risk of OA in the damaged joints, but in most people vigorous, low-impact exercise is beneficial for both it's physical and mental benefits," said lead researcher David Hunter MD PhD, New England Baptist Hospital. "The largest modifiable risk factor for knee OA is body weight, such that each additional kilogram of body mass increases the compressive load over the knee by roughly 4kg".

One might surmise therefore that exercise to reduce body-weight, where necessary, could in fact reduce the risk of OA, rather than increase it.

The knee is the joint most commonly affected by the symptoms of osteoarthritis. More than 10 million Americans suffer from knee osteoarthritis, the most common cause of disability in the United States and women are more commonly affected than men.