One of the best ways to prevent joint trouble is by strengthening the muscles that surround and support the joints.
Shoulders: Most important is maintaining proper posture by keeping the shoulder blades slightly pinched together. Strengthening the deltoids also helps: Stand straight with your abdominal muscles contracted and slowly raise your arms out to the sides to a 90-degree angle. Hold for 5 to 10 seconds, then lower them slowly. Repeat 10 times and add more sets of 10 repetitions as you’re able. Once it gets easy, add two- to three-pound hand weights.

Elbows: Sit at a table and place your forearm flat on the table, palm up. Slowly curl your hand upward, then slowly lower it. Repeat up to 30 times, then switch sides. Use one-pound weights or soup cans for starters and gradually add weight as you’re able. Another idea: Extend your arms straight out in front of you. Flex the hands up, so the fingers are pointing skyward, then down, so they’re pointing to the floor. Repeat 10 times.

Hips: To work the abductor muscles, lie on your right side with your body in a straight line and slowly lift your left leg. Repeat five times, then switch legs. It’s also good to stretch the flexor muscles at the front of the hips, which get stiff from prolonged sitting. Lie on your back with one leg stretched out straight and pull the other knee to your chest. Switch sides.

Knees: William Roberts, M.D., president of the American College of Sports Medicine, recommends mini squats to build up the quadriceps, the muscles on the front of the thighs. Stand straight with your feet six inches apart. Bend your knees slightly (four to six inches) and squeeze your buttocks together. Repeat as many times as possible. Then do it on one leg at a time. Straight leg raises also strengthen the quads. Lie on your back, with one leg bent and the other straight. Slowly raise the straight leg several inches off the floor, hold for 10 seconds, then slowly lower it. Repeat 10 times. As it gets easier, increase the number of sets.

RESOURCES

Websites
Medical-specialty organizations that treat joint conditions have websites full of good information.

The American Academy of Orthopaedic Surgeons: www.aaos.org.

The American College of Rheumatology: www.rheumatology.org.

The National Institute of Arthritis and Musculoskeletal and Skin Diseases: www.niams.nih.gov.

The Arthritis Foundation: www.arthritis.org .

Books
Two books that can answer questions about joint problems and treatments:

The Arthritis Helpbook: A Tested Self-Management Program for Coping With Arthritis and Fibromyalgia, by Kate Lorig and James F. Fries (HarperCollins, $20 at www.barnesandnoble.com).

The American Physical Therapy Association Book of Body Maintenance and Repair, by Steve Vickery and Marilyn Moffat (Henry Holt & Co., $16 at www.amazon.com).