If your friends are happy—turns out you're more likely to be happy too. If your friends are overweight, that too ups the odds you'll pack on pounds.

如果你的朋友很快樂，那你也快樂的可能性很大。如果你的朋友體重超重，那你體重增加的幾率也會(huì)上升。

Those effects have been shown in studies. And now researchers have identified another seemingly contagious quality: exercise.

這些效應(yīng)已經(jīng)被研究證明。現(xiàn)在，研究人員證實(shí)了另一個(gè)似乎具傳染性的東西：鍛煉。

The investigators analyzed the running activity of more than a million individuals worldwide who used an exercise tracking device for five years. And they used weather patterns as a way to randomly examine different parts of that global network.

研究人員分析了全球100多萬(wàn)人的跑步活動(dòng)，這些人5年來(lái)一直在使用運(yùn)動(dòng)追蹤裝置。研究人員運(yùn)用天氣模式對(duì)全球不同地區(qū)進(jìn)行隨機(jī)檢測(cè)。

"If it happens to be a really nice day out, sunny and not too hot, not too cool, that will induce people to run more." Sinan Aral, a computational social scientist at MIT. "If it's a rainy day and cold, that will induce people to stay in more on average."

麻省理工學(xué)院的計(jì)算社會(huì)科學(xué)家希南·阿拉爾表示：“如果趕上好天氣，陽(yáng)光明媚，溫度適中，那外出跑步的人會(huì)更多。但是如果是下雨天，而且很陰冷，那人們更愿意呆在家里。”

And since different cities have different weather patterns, he says, this natural experiment allowed them to ask: Does a rainy day in New York affect running in San Diego?

阿拉爾表示，由于不同的城市有不同的天氣模式，自然實(shí)驗(yàn)使研究人員產(chǎn)生這樣的問題：紐約下雨會(huì)影響圣地亞哥的跑步活動(dòng)嗎？

"If the weather in New York causes changes in the running behavior in San Diego, it can really only be happening thru peer influences of the friends who live between New York and San Diego."

“如果紐約的天氣可以改變圣地亞哥的跑步行為，這只能通過居住在紐約和圣地亞哥的朋友之間的同伴影響產(chǎn)生。”

And that is exactly what he and his colleague saw: that the behavior of one city's runners could indeed affect the behavior of runners in another socially connected city. The study is in the journal Nature Communications.

這就是阿拉爾和同事們得出的結(jié)論：一個(gè)城市跑步者的行為可能的確會(huì)影響與其有社交聯(lián)系的另一個(gè)城市跑步者的行為。這項(xiàng)研究結(jié)果發(fā)表在《自然通訊》期刊上。

A few caveats: women tended to be influenced more by the female runners in their networks. And less active runners tended to influence more active runners to run more, but not so much the other way around. Still, this could be valuable intel for health professionals.

幾點(diǎn)說(shuō)明：女性更容易受其社交圈中的女性跑步者的影響。活躍度低的跑步者會(huì)令活躍度高的跑步者增加跑步距離，但后者對(duì)前者的影響卻不太多。不過，這對(duì)健康專家來(lái)說(shuō)可能仍是個(gè)有價(jià)值的情報(bào)。

"We have to start thinking about consumers and citizens as networked consumers and networked citizens. Where they are influenced by and influence their social network in very strong and dynamic ways, that will change the way a particular intervention succeeds or fails."

“我們要開始將用戶和市民看作網(wǎng)絡(luò)化的用戶和市民。因?yàn)樗麄儠?huì)以非常強(qiáng)烈又動(dòng)態(tài)的方式影響其社交網(wǎng)絡(luò)，或被社交網(wǎng)絡(luò)影響，而這會(huì)改變特殊干涉的成敗。”

In other words -- if your prescription is more exercise? The doctors might want to write a prescription for your friends and family, too.

換而言之，如果你的處方是增加鍛煉，那醫(yī)生或許想讓你的朋友和家人也多運(yùn)動(dòng)運(yùn)動(dòng)。

If your friends are happy—turns out you're more likely to be happy too. If your friends are overweight, that too ups the odds you'll pack on pounds.

如果你的朋友很快樂，那你也快樂的可能性很大。如果你的朋友體重超重，那你體重增加的幾率也會(huì)上升。

Those effects have been shown in studies. And now researchers have identified another seemingly contagious quality: exercise.

這些效應(yīng)已經(jīng)被研究證明。現(xiàn)在，研究人員證實(shí)了另一個(gè)似乎具傳染性的東西：鍛煉。

The investigators analyzed the running activity of more than a million individuals worldwide who used an exercise tracking device for five years. And they used weather patterns as a way to randomly examine different parts of that global network.

研究人員分析了全球100多萬(wàn)人的跑步活動(dòng)，這些人5年來(lái)一直在使用運(yùn)動(dòng)追蹤裝置。研究人員運(yùn)用天氣模式對(duì)全球不同地區(qū)進(jìn)行隨機(jī)檢測(cè)。

"If it happens to be a really nice day out, sunny and not too hot, not too cool, that will induce people to run more." Sinan Aral, a computational social scientist at MIT. "If it's a rainy day and cold, that will induce people to stay in more on average."

麻省理工學(xué)院的計(jì)算社會(huì)科學(xué)家希南·阿拉爾表示：“如果趕上好天氣，陽(yáng)光明媚，溫度適中，那外出跑步的人會(huì)更多。但是如果是下雨天，而且很陰冷，那人們更愿意呆在家里。”

And since different cities have different weather patterns, he says, this natural experiment allowed them to ask: Does a rainy day in New York affect running in San Diego?

阿拉爾表示，由于不同的城市有不同的天氣模式，自然實(shí)驗(yàn)使研究人員產(chǎn)生這樣的問題：紐約下雨會(huì)影響圣地亞哥的跑步活動(dòng)嗎？

"If the weather in New York causes changes in the running behavior in San Diego, it can really only be happening thru peer influences of the friends who live between New York and San Diego."

“如果紐約的天氣可以改變圣地亞哥的跑步行為，這只能通過居住在紐約和圣地亞哥的朋友之間的同伴影響產(chǎn)生。”

And that is exactly what he and his colleague saw: that the behavior of one city's runners could indeed affect the behavior of runners in another socially connected city. The study is in the journal Nature Communications.

這就是阿拉爾和同事們得出的結(jié)論：一個(gè)城市跑步者的行為可能的確會(huì)影響與其有社交聯(lián)系的另一個(gè)城市跑步者的行為。這項(xiàng)研究結(jié)果發(fā)表在《自然通訊》期刊上。

A few caveats: women tended to be influenced more by the female runners in their networks. And less active runners tended to influence more active runners to run more, but not so much the other way around. Still, this could be valuable intel for health professionals.

幾點(diǎn)說(shuō)明：女性更容易受其社交圈中的女性跑步者的影響。活躍度低的跑步者會(huì)令活躍度高的跑步者增加跑步距離，但后者對(duì)前者的影響卻不太多。不過，這對(duì)健康專家來(lái)說(shuō)可能仍是個(gè)有價(jià)值的情報(bào)。

"We have to start thinking about consumers and citizens as networked consumers and networked citizens. Where they are influenced by and influence their social network in very strong and dynamic ways, that will change the way a particular intervention succeeds or fails."

“我們要開始將用戶和市民看作網(wǎng)絡(luò)化的用戶和市民。因?yàn)樗麄儠?huì)以非常強(qiáng)烈又動(dòng)態(tài)的方式影響其社交網(wǎng)絡(luò)，或被社交網(wǎng)絡(luò)影響，而這會(huì)改變特殊干涉的成敗。”

In other words -- if your prescription is more exercise? The doctors might want to write a prescription for your friends and family, too.

換而言之，如果你的處方是增加鍛煉，那醫(yī)生或許想讓你的朋友和家人也多運(yùn)動(dòng)運(yùn)動(dòng)。