跑步事實上使膝蓋更健康！在尚未讀到這一篇文章前，我早已經多年不跑步了，原因就是怕膝蓋受傷，或說是加重膝蓋的傷。讀了這篇報導之後才知道，原來這「想當然耳」的觀念很有可能是錯誤的。

在歐洲奧地利一個跨十年的研究，與美國史丹佛大學長達二十多年的追蹤，這兩個研究都發現：「持續跑步的人膝蓋健康狀況優於沒跑步的人，或說是：持續跑步的人罹患膝蓋病變的人的比例小於優於不跑步的人。」英國的足球菁英有到中年時有近半的人都身受膝蓋疾病所苦，另外舉重選手，也經常飽受膝蓋受傷所苦，而跑步的人顯然沒有那麼高的膝蓋受傷的比例。

一個史丹佛的醫生與工程師們推論：跑步這項的運動使膝蓋的軟骨習慣這種運動方式，與其受力的大小，如果這種跑步動作的平衡被破壞，使膝蓋的運動不再以其慣習的方式運動，才會受傷。所以，最重要的便是一開始就不要受傷！要是受傷了，也要復原了才再開始跑。

所以在讀完這篇報導之後，我也立刻把這篇轉寄給多位跑步或曾經跑步的朋友。

其實，除非實驗組與對照組都是同卵雙胞胎，不然實在不是「真」科學；因為人與人的個體差異很大。所以，對這項的研究結果也可以反過來解釋－天生膝蓋較強壯、不易受傷的人，才可以持續不斷的跑步。膝蓋較易受傷的人，都盡量避免跑步。


August 11, 2009, 11:59 pm

Phys Ed: Can Running Actually Help Your Knees?

By Gretchen Reynolds
Lumilon.com/Getty Images

An article in Skeletal Radiology, a well-respected journal, created
something of a sensation in Europe last year. It reported that researchers from Danube Hospital in Austria examined the knees of marathon runners using M.R.I. imaging, before and after the 1997 Vienna marathon. Ten years later, they scanned the same runners' knees again. The results were striking. "No major new internal damage in the knee joints of marathon runners was found after a 10-year interval," the researchers reported. Only one of the participants had a knee that was truly a mess, and he'd quit running before the 1997 marathon (but had been included in that study anyway). His 1997 knee M.R.I. revealed cartilage lesions, swelling and other abnormalities. In the years that followed, the knee became worse, showing augmented tissue damage and more serious lesions. His exam prompted the researchers to wonder whether he would have been better off persisting as a runner, because, as they speculate, "continuous exercise is protective, rather than
destructive," to knees.


You can't be a runner past the age of 40, as I am, without hearing that running will ruin your knees, by which doomsayers usually mean that we'll develop "degeneration of the cartilage in the kneecap, which -reduces its shock-absorbing capacity," says Ross Tucker, a physiologist in South Africa and co-author of the new book "The Runner's Body: How the Latest Exercise Science Can Help You Run Stronger, Longer and Faster." In other words, we'll be afflicted with arthritis.

It's not an unreasonable supposition; other sports have been linked with early-onset arthritis in knees. In a British study, almost half of the middle-aged, formerly elite soccer players were found to have crippling, bone-on-bone arthritis in at least one knee. Former weight lifters also have a high incidence of the condition, as do retired N.F.L. players.


But despite entrenched mythology to the contrary, runners don't seem
prone to degenerating knees. An important 2008 study, this one from
Stanford University, followed middle-aged, longtime distance runners
(not necessarily marathoners) for nearly 20 years, beginning in 1984,
when most were in their 50s or 60s. At that time, 6.7 percent of the
runners had creaky, mildly arthritic knees, while none of an age-matched control group did. After 20 years, however, the runners' knees were healthier; only 20 percent showed arthritic changes, versus 32 percent of the control group's knees. Barely 2 percent of the runners' knees were severely arthritic, while almost 10 percent of the control group's were. "We were quite surprised," says Eliza Chakravarty, an assistant professor at the Stanford University School of Medicine and lead author of the study. "Our hypothesis going in had been that runners, because of the repetitive pounding, would develop more frequent and more severe arthritis."


Instead, recent evidence suggests that running may actually shield somewhat against arthritis, in part because the knee develops a kind of motion groove. A group of engineers and doctors at Stanford published a study in the February issue of The Journal of Bone and Joint Surgery that showed that by moving and loading your knee joint, as you do when walking or running, you "condition" your cartilage to the load. It grows accustomed to those particular movements. You can run for miles, decades, a lifetime, without harming it. But if this exquisite balance is disturbed, usually by an injury, the loading mechanisms shift, the moving parts of the knee are no longer in their accustomed alignment and a "degenerative pathway" seems to open. The cartilage, like an unbalanced tire, wears away. Pain, tissue disintegration and, eventually, arthritis can follow.


So, the best way to ensure that your knees aren't hurt by running is not to hurt them in the first place. "The biggest predictor of injury is previous injury," Tucker says, and one of the best deterrents against a first (or subsequent) knee injury is targeted strength training. "The hip stabilizers, quads, hamstrings and core must all be strong enough. As soon as there is weakness, some other muscle or joint must take over, and that's when injuries happen."

If you've injured your knee in the past, particularly if you've ever torn an A.C.L. (an injury that, in the Stanford gait study, was closely associated with misalignment and cartilage degeneration), talk to your physician before running. But for most runners, the scientific observations of Chakravarty will ring true. "What struck me," she says, "is that the runners we studied were still running, well into their 70s and 80s." They weren't running far, she says. They weren't running frequently. They averaged perhaps 90 minutes a week. "But they were still running."


http://well.blogs.nytimes.com/2009/08/11/phys-ed-can-running-actually-help-your-knees/?em

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The story in English was taken from the New York Times.  The copyright remains with its original owner.  The author of this story and the New York Times are not involved with, nor endorse the production of this blog.



信義快速道路啟用路跑活動  2005.5.1
Guys after the race (to the right, Frank, Anthony, Masaki, William, Ray and Clark.)