3. Pounding the Pavements.

Running, particularly on the roads, has been blamed for wear and tear on the knees, which can lead to osteoarthritis. but a new study shows that those who regularly run are actually less likely to develop the condition than those who don't. It seems running can strengthen the cartilage around the knee, preventing degeneration.

Researchers at Monash University in Victoria, Australia, followed 300 adults aged between 50 and 79 over a decade and found that cartilage volume increased in those who exercised the most.

Regular running can also reduce pain: a study at California's Stanford University found that older people engaging in regular exercise, including running, reported 25 percent less musculo-skeletal pain than sedentary people.

So does this mean that people with osteoarthritis should exercise? "yes ", says Dr Adam Bajkowski, president of the Primary Care Rheumatology Society, UK. "the more you exercise your joints, the stronger they become."

But Watch Out

"Older people should always get a medical assessment before taking up a new activity and you should build up to running gradually, starting with a power walk," says Claire Small of UK's Chartered Society of Physiotherapy.