About 30 percent of athletes had hip or knee arthritis, compared to 19 percent who weren't athletes.

"Regular exercise is important to health and well being," said Dr. Joseph Buckwalter, who studies osteoarthritis and sports medicine at the University of Iowa, "but certain kinds of exercise expose you to greater risk of injury."

"Elite athletes engage in challenging, physically demanding sports, so they're at higher risk of joint injuries and repetitive joint injuries," said Buckwalter, who was not involved in the study.

Osteoarthritis, also called "wear and tear" arthritis, occurs when the cartilage cushioning your joints wears down. That allows bones to rub together, which can cause pain, swelling and limited range of motion.

An estimated 27 million U.S. adults had osteoarthritis in 2005, according to the Centers for Disease Control and Prevention.

The study, published in the American Journal of Sports Medicine, included more than 700 retired Swedish athletes aged 50 to 93 who had played professional and Olympic level sports and nearly 1,400 men of the same age who exercised a little or not at all.

The group of retired athletes included men involved in high-contact sports such as soccer and hockey, and those who participated in non-contact sports like running, swimming and cycling.

The researchers found the risk of having hip or knee arthritis was 85% higher in elite athletes. And in athletes who had joint surgery, the risk more than doubled.

Greater risk was seen in high contact sports, with a doubled risk in soccer and handball (also known as team handball) players and a tripled risk in ice hockey players.

If you're a weekend warrior or a young athlete, you may not have to worry about the results from the study, noted co-author Dr. Magnus Tveit at Lund University in Sweden.

"But if you're an overweight, middle-aged runner who wants to run at an intense level, there are better ways of staying in shape without risking a knee injury," he wrote in an email.

Buckwalter recommends activities that don't have the same risk of injury such as swimming, cycling, moderate running and yoga.

"There are strategies in every sport to decrease injury," he told Reuters Health. "That includes proper form and overall fitness regimen. And if you have an injury, make sure you're recovered and rehabilitated before returning to the sport."

Dr. John Wilson, who specializes in primary care sports medicine at the University of Wisconsin but was not part of the study, noted that physical activity regardless of the type of sport may have health benefits that outweigh the risk of arthritis.

"Playing a sport offers so many benefits like cardiovascular fitness, lower rates of obesity and lower blood pressure," he said, "not mention other benefits like confidence building and teamwork that comes from being on a team."

SOURCE: bit.ly/uSjtXd American Journal of Sports Medicine, December 8, 2011.

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