科学美国人60秒：减肥不一定能长寿，但增肌也许可以

This is Scientific American — 60-Second Science. I'm Christopher Intagliata. Got a minute?

这里是《科学美国人》的60秒科学，我是克里斯多夫·因塔利亚塔。准备好了吗?

Doctors routinely measure a patient's body-mass index, or BMI. And if that weight-to-height ratio points to obesity, the doc might prescribe exercise, to shed the extra pounds. But when it comes to longevity, a focus onweight loss may be misplaced. Because BMIisn't actually a very reliable indicator of lifespan. A more useful measure, some physicians say, might be muscle mass.

医生通常会测量病人的体重指数(BMI)。如果体重与身高的比例表明肥胖，医生可能会建议锻炼，减掉多余的体重。但说到长寿，把重点放在减肥上可能是错误的。因为BMI实际上并不是寿命的可靠指标。一些医生说，更有用的测量方法可能是肌肉质量。

Researchers analyzed BMI and muscle mass data from more than 3,600 seniors in a long-term study. And they tracked which seniors had died, a decade later. Turns out BMI wasn't much good at predicting chance of death.

研究人员在一项长期研究中分析了3600多名老年人的体重指数和肌肉质量数据。十年后，他们追踪了老年人的去世情况。事实证明，BMI并不能很好地预测死亡率。

But muscle mass was: more muscle meant better odds of survival. The study appears in The American Journal of Medicine.

但肌肉质量可以:更多的肌肉意味着更大的生存几率。这项研究发表在《美国医学杂志》上。

There's no cause-and-effect here—just correlation for now. But study author Preethi Srikanthan, of UCLA, has this recommendation: "Get up and start moving. Focus on trying to maintain the maximum amount of resistance training that you can, and stop worrying so much about dropping calories." Which could take a little weight off your mind, too.

目前肌肉质量与死亡率之间没有因果关系，只有相关性。但该研究的作者、加州大学洛杉矶分校的普里埃蒂·斯里坎森建议:“站起来，开始运动。专注于尽可能保持最大限度的阻力训练，不要太纠结于减少卡路里。”这样也能减轻你想要减肥的压力。

Thanks for the minute for Scientific American — 60-Second Science. I'm Christopher Intagliata.

感谢收听《科学美国人》的60秒科学。克里斯多夫·因塔利亚塔报道。