保持健康要日行一萬步？4400步就夠了

今天你走夠一萬步了嗎？各種計步軟件都提醒我們，每天走一萬步有利健康。然而研究人員近日表示，每天要走一萬步的想法是荒誕的，每天行走4400步就足以降低早亡的風險。

2018年8月26日，遼寧瀋陽，徒步遼寧2018全民健身日系列活動舉行，萬人參與徒步活動。

There's nothing magical about the number 10,000.

一萬這個數字沒什麼神奇的。

In fact, the idea of walking at least 10,000 steps a day for health goes back decades to a marketing campaign launched in Japan to promote a pedometer. And, in subsequent years, it was adopted in the US as a goal to promote good health. It's often the default setting on fitness trackers, but what's it really based on?

事實上，爲了健康每天至少走一萬步的想法可以追溯到幾十年前日本一個計步器的營銷活動。在隨後的幾年裏，它成爲一種促進健康的目標在美國被採納。健身追蹤器的默認設置也是一萬步，但這背後真正的原理是什麼呢？

pedometer[pɪ'dɒmɪtə]：計步器

default setting：默認設置

"The original basis of the number was not scientifically determined," says researcher I-Min Lee of Brigham and Women's Hospital.

布里格姆女子醫院的研究員李依敏說：“這個數字的最初依據沒有科學上的驗證。”

She was curious to know how many steps you need to take a day to maintain good health and live a long life, so she and her colleagues designed a study that included about 17,000 older women. Their average age was 72. The women all agreed to clip on wearable devices to track their steps as they went about their day-to-day activities.

她很想知道人們每天需要走多少步才能保持健康和長壽，所以她和同事們設計了一項有1.7萬名老年女性參與的研究。她們平均72歲，這些女性都同意在日常活動中佩戴可穿戴設備，跟蹤自己的步數。

It turns out that women who took about 4,000 steps per day got a boost in longevity, compared with women who took fewer steps. "It was sort of surprising," Lee says.

結果表明，每天走大約4000步的女性比每天步數少於4000步的女性長壽。“這有點令人驚訝，”李依敏說。

In fact, women who took 4,400 steps per day, on average, were about 40 percent less likely to die during the follow-up period of about four years compared with women who took 2,700 steps. The findings were published Wednesday in JAMA Internal Medicine.

事實上，與每天走2700步的女性相比，平均每天走4400步的女性在大約四年的隨訪期間死亡的可能性要低40%。該研究結果於上週三（5月29日）發表在《美國醫學會內科雜誌》上。

Another surprise: The benefits of walking maxed out at about 7,500 steps. In other words, women who walked more than 7,500 steps per day saw no additional boost in longevity.

另一個意外是：步行的好處在7500步左右達到了極限。換句話說，每天步行超過7500步的女性壽命並沒有進一步增加。

"I love this study. I think it's really good news for women who may not be particularly active," says Kathleen Janz, who studies how physical activity influences health at the University of Iowa. She was not involved in this study.

“我喜歡這個研究。我認爲這對沒有特別積極鍛鍊的女性來說是個好消息，”愛荷華大學研究體育活動如何影響健康的凱瑟琳·揚茨說。她沒有參與這項研究。

Janz, who helped shape the new federal exercise recommendations released last November, says the message that comes from this study is that older women can benefit from just light walking.

揚茨協助了去年11月新的聯邦運動建議的發佈。她說，這項研究告訴我們，老年婦女可以從輕鬆適度的步行中獲益。

"They didn't need to go to the gym or invest in a personal trainer or exercise equipment," she says. All they had to do was walk.

她說：“她們不需要去健身房，也不需要花錢請私教或購買健身器材。”她們只要走走路就好。

And Janz says that's encouraging.

揚茨說，這個發現令人鼓舞。

"To me, this study suggests there's more benefit to light activity than we were previously thinking there might be," she says.

她說：“對我來說，這項研究表明，輕度活動的好處比我們之前認爲的要多。”

Of course, the researchers point out, they would like to know much more about how walking may affect other health parameters such as quality of life and memory and cognitive function. It's possible that walking a greater number of steps each day could influence these outcomes.

當然，研究人員指出，他們想知道更多關於步行如何影響其他健康參數的信息，如生活質量、記憶力和認知功能。每天走更多步可能會影響這些結果。

Another thing Janz notes is that this study only measures walking. It didn't measure things that many of us do that don't require steps, things like gardening, swimming or biking. And it's safe to assume some women in the study were doing these other things that can influence health as well.

揚茨還注意到，這項研究只研究了步行。它沒有測量我們很多人做的不需要步行的事情，比如園藝、游泳或騎自行車。可以肯定的是，這項研究中的一些女性也在做這些會影響健康的事情。

And Janz says to remember the federal exercise guidelines call for 150 minutes per week of moderate physical activity, which includes all kinds of daily movement, not just steps.

揚茨說，要記住聯邦運動指南要求每週進行150分鐘的適度體育活動，包括各種日常運動，而不僅僅是步行。

So, if 10,000 steps has been feeling out of reach to you, it may be time reset those factory settings on your fitness tracker. Instead, try to hit at least 4,400 a day, along with daily activities that you enjoy. And stick to it.

所以，如果你覺得1萬步已經遙不可及，那麼是時候在你的健身追蹤器上重置這些出廠設置了。你可以試着每天至少走4400步，再做些你喜歡的日常活動，並堅持下去。