How Many Steps to Take for Good Health?
Older women who walk a little over three kilometers each day might live longer than less active women of the same age, a new study suggests.
Many Americans hoping to stay healthy set a daily goal of 10,000 steps, or about eight kilometers. They often have this goal because they are wearing electronic devices which set that target, note researchers in the United States. Their findings appeared recently in the publication JAMA Internal Medicine.
But it is not clear how much intensity or speed matter when counting the health benefits of every step, the researchers write. They add that 10,000 steps per day might not be the right goal for everyone.
For the study, researchers observed 17,000 women, all in their early 70s. They asked the women to wear accelerometers for at least four days. Accelerometers are small devices that measure the number of steps and the intensity of movement.
The researchers followed up with the women much later, around 4.3 years later, on average. Since the beginning of the study, 504 women had died. Compared to women who took no more than 2,718 steps daily, the women who took at least 4,363 steps per day were 41 percent less likely to die.
"Even a modest amount of steps is associated with lower mortality," said I-Min Lee, the lead writer of a report on the study. She is a doctor with Harvard Medical School and Brigham and Women's Hospital in Boston, Massachusetts.
The women who took more steps had "lower mortality rates until about 7,500 steps per day, beyond which no further declines were observed," Lee told the Reuters news agency. "The rate of stepping did not matter in these older women; it was the number of steps that mattered."
This suggests that the number of steps, rather than intensity, may be more important for a long life among older women.
The study had a few limitations. For example, the researchers only measured women's movements once, at the start of the study period. It is possible that the women's behaviors changed over time.
Still, the results are "good news for older adults who may have difficulty walking at faster paces," said Keith Diaz, a researcher at Columbia University Medical Center in New York City. He was not involved in the study.
"Any walking is better than nothing," Diaz said by email. "With even small amounts of walking, your risk of death will be sharply reduced."
"For those who have difficulty walking, other research shows that any form of aerobic activity provides health benefits," he added.
"Swimming, bicycling, arm cranking or any form of activity that is continuous in nature will provide health benefits."
I'm John Russell.
1.at least 至少
He's been away for at least a week.
2.involved in 参与
They have been involved in a campaign of deceit.
3.aerobic activity 有氧运动
Warming up may help prepare your body for aerobic activity.
4.follow up 跟踪
We will continue to follow up and find the source of these goods and where they are coming from.
5.But it is not clear how much intensity or speed matter when counting the health benefits of every step, the researchers write.
it is not clear 目前不清楚
It is not clear whether the president is willing to negotiate with the democrats
Interestingly, it is not clear which solution the prime minister favors.
6.The researchers followed up with the women much later, around 4.3 years later, on average.
on average 平均的
American shares rose, on average, by 38%.
On average each report requires 1,000 hours to prepare.
许多希望保持健康的美国人制定了日行一万步（约八公里）的目标 。美国研究人员指出，他们经常设定这样的目标，因为他们佩戴着计步的电子设备 。他们的发现最近发表在《美国医学会内科杂志》上 。
但研究人员写道，在计算每一步带来的健康益处时，尚不清楚强度或速度对健康的影响程度 。他们补充说，日行一万步的目标可能并不适用所有人 。
在这项研究中，研究人员观察了17000名70岁出头的女性 。他们要求这些女性佩戴加速度计至少4天 。加速度计是一种记录步数和运动强度的小型设备 。
随后，研究人员在平均约4.3年后对这些女性进行了跟踪调查 。自研究开始以来，已有504名女性离世 。与每天行走不满2718步的女性相比，每天至少步行4363步的女性的死亡率低41% 。
关于这项研究报告的首席作者I-Min Lee说:“即使是少量的步行也能降低死亡率 。”她是哈佛医学院和马萨诸塞州波士顿布里格姆女子医院的医生 。
Lee告诉路透社，每天步行久一些的女性“死亡率较低，上限为日行7500步左右，超过（该标准）并没有进一步下降的迹象” 。“在这些年龄较大的女性中，走路速度并不重要；重要的是步数 。”
该研究有一定的局限性 。例如，研究人员只在研究开始时测量了女性的单次行走 。这些女性的行为可能会随着时间改变 。
尽管如此，纽约哥伦比亚大学医学中心的研究人员基思·迪亚兹（Keith Diaz）称，研究结果“对那些难以快速行走的老年人来说是个好消息” 。他没有参与这项研究 。
迪亚兹在电子邮件中称:“走路总比不动弹有益 。”“即使少量的步行，你的死亡风险也会大大降低 。”