久坐傷“心”，快動起來吧！

Sitting quietly for extended periods of time could be hurting your heart, according to a surprising new study. It finds that the more people sit, the greater the likelihood that they will show signs of injury to their heart muscles.

一項令人驚訝的新研究發(fā)現(xiàn)，長時間靜坐可能會傷害你的心臟。研究發(fā)現(xiàn)，坐的時間越長，就越有可能出現(xiàn)心肌受損的跡象。

We all have heard by now that sitting for hours on end is unhealthy, even if we also occasionally exercise. People who sit for more than about nine or 10 hours each day — a group that includes many of us who work in offices — are prone to developing diabetes, heart disease and other problems, and most of these risks remain relatively high, even if we exercise.

我們現(xiàn)在都聽說，連續(xù)幾小時坐著是不健康的——即使偶爾也鍛煉一下。每天坐9個或10個小時以上的人——包括許多在辦公室工作的人——容易患糖尿病和心臟病等疾病，即使鍛煉，風險依然相對較高。

Excessive sitting also has been associated with heart failure, a condition in which the heart becomes progressively weaker and unable to pump enough blood to keep the rest of the body oxygenated and well. But how sitting, which seems to demand so little from the heart, could be linked to heart failure, a condition in which the heart cannot respond adequately to exertion, has been unclear.

久坐也與心力衰竭相關(guān)，也就是，心臟變得越來越虛弱，無法泵出足夠的血液，為身體其他部分充分供氧，保證它們健康運行。但是，久坐似乎對心臟的要求很少，所以尚不清楚為什么它會與心力衰竭相關(guān)聯(lián)。心力衰竭是指心臟無法充分做出反應(yīng)、正常運行的疾病。

So recently a group of cardiologists from around the world began to wonder about troponins.

前不久，世界各地的一群心臟病學(xué)家開始研究肌鈣蛋白。

Troponins are proteins produced by cardiac-muscle cells when they are hurt or dying. A heart attack releases a sudden tsunami of troponins into the bloodstream.

肌鈣蛋白是心肌細胞在受傷或死亡時產(chǎn)生的蛋白質(zhì)。心臟病發(fā)作時會突然釋放大量肌鈣蛋白進入血液。

But even slightly elevated troponin levels, lower than those involved in heart attacks, are worrisome if they persist, most cardiologists believe. Chronically high troponin levels indicate that something is going wrong inside the heart muscle and that damage is occurring and accruing there. If the damage is not halted or slowed, it could eventually result in heart failure.

但是，大多數(shù)心臟病專家認為，就算肌鈣蛋白水平只是略高——低于心臟病發(fā)作時的水平——如果這種情況長期存在，也令人擔憂。長期高肌鈣蛋白水平表明，心肌內(nèi)部出了問題，損害正在發(fā)生，而且在不斷增加。如果損傷沒有停止或減緩，最終會導(dǎo)致心力衰竭。

No research, however, had ever examined whether sitting was associated with high troponin levels.

不過，還沒人研究過久坐是否與高肌鈣蛋白水平有關(guān)。

So for the new study, published in Circulation, the researchers turned to existing data from the Dallas Heart Study, a large, ongoing examination of cardiac health among a group of ethnically diverse men and women, overseen by the University of Texas Southwestern Medical Center. The study’s participants had completed cardiac testing, given blood samples and health information and worn activity trackers for a week.

因此，在《循環(huán)》雜志(Circulation)上發(fā)表的一項新研究中，研究人員研究了達拉斯心臟研究(Dallas Heart Study)的現(xiàn)有數(shù)據(jù)。該研究是德克薩斯大學(xué)西南醫(yī)學(xué)中心(University of Texas Southwestern Medical Center)針對不同種族的男性和女性持續(xù)進行的一項大型心臟健康研究。該研究的參與者完成了心臟測試，提供了血液樣本和健康信息，并佩戴活動追蹤器一周。

The researchers pulled information about more than 1,700 of these participants, excluding any who had heart disease or symptoms of heart failure, such as chest pain or shortness of breath.

研究人員收集了1700多名參與者的信息，排除了任何有胸痛或呼吸短促等心臟病或心衰癥狀的人。

They checked the men’s and women’s blood samples for troponins and the readouts from their activity trackers to see how much or little they had moved most days.

他們查看了這些男性和女性血液樣本中的肌鈣蛋白，以及他們活動追蹤器的讀數(shù)，看看他們在大多數(shù)日子里活動了多少。

Then they made comparisons.

然后他們進行了比較。

Many of the study participants turned out to be sitters, remaining sedentary for as much as 10 hours or more on most days. Not surprisingly, those men and women rarely exercised.

這項研究的許多參與者都是久坐者，在大多數(shù)日子里每天坐著的時間長達10個小時以上。毫不奇怪，這些男性和女性很少鍛煉。

Some of the men and women did work out, though, usually by walking. They were not exercising a lot, but the more exercise they undertook, the fewer hours they sat, on average.

不過，有些男性和女性確實鍛煉，通常是走路。他們鍛煉得不是很多，但他們鍛煉得越多，平均坐著的時間就越短。

And this physical activity, limited as it was, was associated with relatively normal levels of troponin. The people who moved the most tended to have lower amounts of troponin in their blood, although the benefits statistically were slight.

這種體育活動雖然具有局限性，卻與相對正常的肌鈣蛋白水平有關(guān)?；顒幼疃嗟娜搜褐屑♀}蛋白的含量更低，盡管從統(tǒng)計學(xué)角度講，益處微乎其微。

On the other hand, the people who sat for 10 hours or more tended to have above-average troponin levels in their blood. These levels were well below those indicative of a heart attack. But they were high enough to constitute “subclinical cardiac injury,” according to the study’s authors.

另一方面，坐10個小時以上的人血液中肌鈣蛋白的水平高于平均水平。他們的肌鈣蛋白水平遠低于心臟病發(fā)作時的水平。但該研究的作者們表示，這種水平足以構(gòu)成“亞臨床心臟損傷”。

This relationship remained strong, even after the researchers controlled for other factors that could have influenced troponin levels, including age, gender, body mass index and cardiac function.

即使在研究人員對照了可能影響肌鈣蛋白水平的其他因素之后——包括年齡、性別、體重指數(shù)和心臟功能——這種關(guān)聯(lián)性依然強烈。

Overall, sitting was more strongly associated with unhealthy troponin levels than exercise was with desirable amounts.

總的來說，久坐與不健康肌鈣蛋白水平的關(guān)系，比鍛煉與理想水平的關(guān)系更密切。

Of course, this was an observational study and can show only that sitting is linked to high troponin, not that it causes troponins to rise.

當然，這是一項觀察性研究，只能表明久坐與高肌鈣蛋白有關(guān)聯(lián)，并不能表明久坐會導(dǎo)致肌鈣蛋白水平升高。

It also cannot explain how physical stillness might injure cardiac cells.

它也無法解釋為什么身體靜止會損傷心肌細胞。

But the impacts are probably indirect, says Dr. James de Lemos, a cardiologist and professor at UT Southwestern Medical Center who oversaw the new study.

不過，負責這項新研究的心臟病專家、德克薩斯大學(xué)西南醫(yī)學(xué)中心教授詹姆斯·德萊莫斯博士(James de Lemos)表示，這種影響很可能是間接的。

“Sedentary behavior is associated with obesity, insulin resistance and fat deposition in the heart, all of which can lead to injury to heart cells,” he says.

“久坐與肥胖、胰島素抵抗和心臟脂肪堆積有關(guān)，這些都可能導(dǎo)致心臟細胞受損，”他說。