If you’ve never complained of knee pain, consider yourself lucky. The knee is the largest joint in the body and one of the most commonly injured.

While acute or overuse injuries are the most common causes of knee pain, arthritis is also a common source of discomfort.

To avoid knee pain and injuries, there are some things you can do to help keep your knees healthy and strong, says Dr. Beau Konigsberg, an orthopedic surgeon at Nebraska Medicine.

One of the most important of these is to maintain a healthy weight, says Dr. Konigsberg. Losing as little as 5 percent of your body weight can dramatically reduce your chances of developing knee arthritis, which is the most common cause of knee pain among people in their 60s and 70s, says Dr. Konigsberg. It is estimated that every extra pound you pack on puts about four extra pounds of pressure on your knees.

Staying active is also key to keeping the knee joint supple and to prevent injury, he says. A knee that isn’t used stiffens and the muscles around it will weaken.

Maintaining flexibility, as well as regular strengthening exercises is also important. Focus on the muscles and tendons that connect directly to the knee, such as the hamstrings and the quadriceps, which help support the knees and reduce stress on the knee joints.

There has also been a lot of attention in the news surrounding glucosamine and chondroitin. “While there have been no studies that have proven these supplements can regrow cartilage or slow the degenerative process,” says Dr. Konigsberg,  “some people swear that they provide some relief of knee pain.”

If knee pain becomes debilitating, it might be time to consider a knee replacement. Thousands of knee replacements are performed each year, and for many people, they provide significant relief and a return to mobility, notes Dr. Konigsberg. If you have lost weight, tried anti-inflammatories and cortisone injections and still have significant pain that may be waking you up at night, it may be time to consider a knee replacement.

“A knee replacement is considered only after all other treatment options have been exhausted,” says Dr. Konigsberg.

For 70-year-old Dennis Chin, a knee replacement allowed him to resume his favorite pastime—playing golf. Chin had injured his knee several times in high school sports and had undergone several arthroscopic knee surgeries.

Over the years, the pain in his knee returned and gradually got worse. When he retired, he stepped up his golf game, which made the pain worse. “I was using my club as a crutch and taking Aleve everyday,” he says.

But when the pain began waking him up at night and he could barely get through a golf game, Chin knew he had to do something. Dr. Konigsberg took X-rays and said there was so much damage that his only real option was a knee replacement.

Chin had a knee replacement in January 2013 and was back on the golf course by March. Now he plays five times a week and sometimes twice a day.

“I have no pain and I’m not limping anymore,” says Chin. “No one can even tell that I had an operation.”

Chin couldn’t be happier. He’s doing what he loves and that’s what retirement is all about.