Strong quadriceps muscles — those at the front of the thigh — are a must for anyone who wants to fly downhill on skis, attempt a double a,el on skates or scale a mountain by foot or by bike. These muscles do more than help you straighten your legs and stand; they’re integral in everything from walking to high jumping.

But they may have special importance for people with knee osteoarthritis.

A recent study of people with the condition found that those who had stronger quadriceps had less cartilage loss behind the kneecap. Less cartilage loss can mean better range of motion and less discomfort.

虽然专家们都认同肥胖、受伤和遗传因素会引致膝骨性关节炎，但至于不同的运动对关节带来的影响，大家则未能确定。不过，他们确知的事是，加强大腿股四头肌的力量，可减低关节进一步受损的机会。报道说：

Most e,perts agree that e,cess weight, injury and a genetic predisposition contribute to knee osteoarthritis, but they’re less sure about the effect of various types of e,ercise. They point out, however, that strengthening the quadriceps could prevent further damage.

“It helps stabilize the patella (髌骨) [a flat, triangular bone covering the surface of the knee joint] and prevents it from moving laterally and tracking abnormally in the knee,” Amin [Dr. Shreyasee Amin, assistant professor of medicine at the Mayo Clinic in Minnesota and lead author of the study] says. “When it’s not aligned in the knee groove properly, you can have more cartilage loss from the friction.”

LA Times 的报道并另闢栏目，介绍4种锻鍊大腿股四头肌的方法。

膝关节问题颇杂复(我不懂)，不少中年男女都有不同程度的膝痛问题。我的左腿有膝关节痛，上楼梯时便有轻度痛楚，左腿有时候因为痛楚或无力而不能独力承托全身。我的右腿本来也有膝关节痛，但不知怎样约1年多后自动痊癒。

作者：Paul Cheung