運動究竟是如何讓我們保持年輕的

How Exercise Keeps Us Young

運動究竟是如何讓我們保持年輕的

Active older people resemble much younger people physiologically, according to a new study of the effects of exercise on aging. The findings suggest that many of our expectations about the inevitability of physical decline with advancing years may be incorrect and that how we age is, to a large degree, up to us.

一項關于運動對衰老影響的最新研究表明，從生理學角度講，經(jīng)常運動的老年人更接近于年輕人。我們一直以為，隨著歲月的流逝，體能的下降不可避免，但這一新發(fā)現(xiàn)表明，上述那些觀點可能有很多并不正確，我們年齡幾何在很大程度上取決于我們自己。

Aging remains a surprisingly mysterious process. A wealth of past scientific research has shown that many bodily and cellular processes change in undesirable ways as we grow older. But science has not been able to establish definitively whether such changes result primarily from the passage of time — in which case they are inevitable for anyone with birthdays — or result at least in part from lifestyle, meaning that they are mutable.

老齡化對于我們來說依舊是一個十分神秘的過程。過去的許多科學研究都表明，隨著年齡的增長，身體和細胞中的許多進程都會出現(xiàn)不利的變化。但科學一直未能明確發(fā)生這些變化的主要原因是時間的推移還是(至少從一定程度上說)個人的生活方式。如果是前者，它們就是每個人從出生起就不可避免的;但如果是后者，這就意味著，它們可以被改變。

This conundrum is particularly true in terms of inactivity. Older people tend to be quite sedentary nowadays, and being sedentary affects health, making it difficult to separate the effects of not moving from those of getting older.

在考慮運動量不足這個因素時，這個謎題顯得尤其復雜難解。當下的老年人往往容易久坐不動，這種生活習慣會影響健康，因此很難區(qū)分運動量不足的后果和單純因為年紀漸長造成的影響。

In the new study, which was published this week in The Journal of Physiology, scientists at King’s College London and the University of Birmingham in England decided to use a different approach.

本周發(fā)表于《生理學雜志》(The Journal of Physiology)上的新研究中，英國倫敦國王學院(King’s College London)和伯明翰大學(University of Birmingham)的科學家們決定使用一種不同的方法。

They removed inactivity as a factor in their study of aging by looking at the health of older people who move quite a bit.

他們選擇了堅持大量運動的健康老年人作為研究對象，這樣就把運動量不足這個因素從研究中去除了。

“We wanted to understand what happens to the functioning of our bodies as we get older if we take the best-case scenario,” said Stephen Harridge, senior author of the study and director of the Centre of Human and Aerospace Physiological Sciences at King’s College London.

該研究的責任作者，倫敦大學國王學院人類和航空航天生理科學中心(Centre of Human and Aerospace Physiological Sciences)主任史蒂芬·哈里吉(Stephen Harridge)說：“我們希望了解在最佳情況下，當我們衰老時身體的功能運作會是怎樣的。”

To accomplish that goal, the scientists recruited 85 men and 41 women aged between 55 and 79 who bicycle regularly. The volunteers were all serious recreational riders but not competitive athletes. The men had to be able to ride at least 62 miles in six and a half hours and the women 37 miles in five and a half hours, benchmarks typical of a high degree of fitness in older people.

為了實現(xiàn)這個目標，科學家們招募了年齡介于55歲至79歲之間，且經(jīng)常騎自行車的85名男性和41名女性。這些志愿者們都是正兒八經(jīng)的騎車愛好者，但并非競技運動員。參與研究的男性必須能在六個半小時內(nèi)騎行至少62英里，女性則需要能在五個半小時內(nèi)騎行37英里，對于老年人而言，能達到這個標準通常身體都非常強健。

The scientists then ran each volunteer through a large array of physical and cognitive tests. The scientists determined each cyclist’s endurance capacity, muscular mass and strength, pedaling power, metabolic health, balance, memory function, bone density and reflexes. They also had the volunteers complete the so-called Timed Up and Go test, during which someone stands up from a chair without using his or her arms, briskly walks about 10 feet, turns, walks back and sits down again.

科學家們對每名志愿者都進行了大量生理和認知測試。他們測定了每名騎車運動者的耐力、肌肉量和力量、蹬力、新陳代謝健康、平衡力、記憶力、骨密度和反射等，還要求志愿者們完成名為“計時起立行走(Timed Up and Go)”的測試，即，不借助手臂的力量從椅子上站起，快步走出大約10英尺的距離，然后轉(zhuǎn)身走回，再度坐下。

The researchers compared the results of cyclists in the study against each other and also against standard benchmarks of supposedly normal aging. If a particular test’s numbers were similar among the cyclists of all ages, the researchers considered, then that measure would seem to be more dependent on activity than on age.

研究人員對參與研究的各位騎車運動者的測試結果進行了兩兩比較，還將這些數(shù)據(jù)與理論上正常衰老下的基準數(shù)據(jù)進行了比較。如果某一特定測試的結果在所有年齡段的騎車運動者中大致相同，那么研究人員就認定該指標更多地取決于體育運動，而不是年齡。

As it turned out, the cyclists did not show their age. On almost all measures, their physical functioning remained fairly stable across the decades and was much closer to that of young adults than of people their age. As a group, even the oldest cyclists had younger people’s levels of balance, reflexes, metabolic health and memory ability.

分析結果證明，年齡對這些騎車運動者的影響并不明顯。從幾乎所有的指標上都能看出，數(shù)十年來，他們的生理機能保持得相當穩(wěn)定。在這方面，他們與同齡人之間的差距遠遠大于他們與年輕人之間的差距。就整個群體而言，哪怕是其中年紀最大的騎車運動者的平衡力、反射、新陳代謝健康和記憶力都處于年輕人的水平。

And their Timed Up and Go results were exemplary. Many older people require at least 7 seconds to complete the task, with those requiring 9 or 10 seconds considered to be on the cusp of frailty, Dr. Harridge said. But even the oldest cyclists in this study averaged barely 5 seconds for the walk, which is “well within the norm reported for healthy young adults,” the study authors write.

他們的“計時起立行走”測試的結果就是一個典范。哈里吉博士指出，許多老年人都至少需要7秒才能完成任務，如果需要9秒或10秒，則認為他們的體制較弱。但在該研究中，即便是年紀最大的騎車運動者平均也僅需5秒就能完成任務，這“完全是健康的年輕成年人的能力范疇”，論文作者寫道。

Some aspects of aging did, however, prove to be ineluctable. The oldest cyclists had less muscular power and mass than those in their 50s and early 60s and considerably lower overall aerobic capacities. Age does seem to reduce our endurance and strength to some extent, Dr. Harridge said, even if we exercise.

然而，研究也證明，衰老的某些方面確實不可避免。年紀最大的騎車運動者的肌肉力量和肌肉量都少于50多歲和60歲剛出頭的參與者，且他們的整體有氧能力也有大幅降低。哈里吉博士說：就算進行體育鍛煉，年齡也確乎會在一定程度上降低我們的耐力和力量。

But even so, both of those measures were higher among the oldest cyclists than would be considered average among people aged 70 or above.

但即便如此，研究中年紀最大的騎車運動者的這兩項指標也均高于70歲或70歲以上人群的平均水平。

All in all, the numbers suggest that aging is simply different in the active.

總而言之，研究數(shù)據(jù)表明，在經(jīng)常進行體育運動的人中，衰老程度完全不同。

“If you gave this dataset to a clinician and asked him to predict the age” of one of the cyclists based on his or her test results, Dr. Harridge said, “it would be impossible.” On paper, they all look young.

哈里吉博士說：“如果你把這個數(shù)據(jù)集交給臨床醫(yī)生，他很可能無法根據(jù)其中某一騎車運動者的測試結果預測出其真實年齡。”單就紙面數(shù)據(jù)而言，這些人看起來都像是年輕人。