If knees were made to last a lifetime, then why are about half a million knee replacements done in the United States each year? They can't all be blamed on marathon running. More likely culprits for bum knees are bad habits that start long before you'll even think of cashing in your IRA. Here are the leading troublemakers -- and the ways to change them before the damage is done:
1. Carrying around extra pounds. If you're significantly overweight, losing even 11 pounds can cut your risk of knee osteoarthritis in half, according to one study. That's because holding up lots of excess weight speeds the breakdown of cushioning cartilage in your knee joints, inviting painful osteoarthritis (OA). And that's why having a body mass index (BMI) of 25 or more is one of the biggest risk factors for developing bad knees.
Related: Calculate your BMI here.
2. "I'll start tomorrow." Putting off exercise doesn't do a thing to keep the muscles that surround and support your knees strong. Strengthening your quads just a little will cut your risk of knee arthritis by as much as 30%. Aim for at least 30 minutes of low-impact activity -- walking, biking, swimming, strength training, doing yoga -- on most days.
3. Overusing your knees. Doing the same exercise over and over and over loosens tendons and damages cartilage, opening the door to injuries and arthritis. Vary your workouts, mixing in some knee-friendly yoga, water aerobics, or tai chi with lunges, squats, and high-impact step aerobics. Already have twinges of knee pain now and then?These moves will relieve discomfort and get your knees back in the game.
4. Slumping. When you tilt forward at the shoulders, your joints, muscles, and ligaments strain to hold you upright. Ditto when you stand with one hip jutting out or your knees locked. Practice standing with your tummy tight, back straight, knees relaxed, and weight evenly distributed between your two feet.
5. Wearing teeter-totter shoes. Stilettos are largely to blame, but any shoe that distributes your weight unevenly stresses your knee joints and throws off your stride. Give your shoes a reality check and save the 4-inch strappy Jimmy Choo clones for special -- and brief -- occasions.
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