过去十年，关于健身运动我们知道了些什么

A Decade of Fitness

　　For the past 10 years (and change), I have been covering exercise science in this column. During that time, I have seen interest in high-intensity exercise soar and enthusiasm for barefoot running fizzle. We have learned contracting muscles talk to baby neurons, creativity blooms from walking, a minute of exertion can be ample, aging is elastic and a chubby dog may be our best exercise motivator.

　　在过去10年多一点的时间里，我一直在这个专栏做健身科学报道。在这期间，我看到人们对高强度运动的兴趣高涨，对赤脚跑步的热情减退。我们了解到，收缩肌肉可以影响婴儿的神经元，散步可以促进创造力，一分钟的锻炼是足够的，衰老是可以改善的，一只胖狗可能是最好的锻炼激励。

　　With 2019 ending, I thought it worthwhile to look back at some of the persistent themes, revelations and surprises from the past decade in fitness.

　　随着2019年的结束，我觉得有必要回顾一下过去十年健身运动中持续出现的主题、发现和意外。

　　Perhaps most obviously, this has been a decade of greatest HIITs, with multiple studies and subsequent columns reiterating that super-short, strenuous workouts — known as high-intensity interval training — improve fitness and health to about the same extent as much longer, more moderate exercise. Since 2010, I have covered seven-minute, four-minute, one-minute, 20-second and 10-second interval routines, with each workout’s declining length increasing its allure. For many of us, the exercise of choice may be the briefest.

　　也许最明显的是，这十年是高强度间歇训练(HIIT)发展最快的十年，多项研究和随后的专栏文章都不断重申，这种超短、高强度的锻炼，和时间长很多且较和缓的锻炼比起来，对体能和健康的改善效果是差不多的。从2010年开始，我介绍过7分钟、4分钟、1分钟、20秒和10秒的间歇训练，时间越短越受欢迎。对我们许多人来说，首选的健身可能就是最短的那个。

　　At the same time, though, a wealth of other studies this decade underscored that gentle exercise is also meaningful, even if it barely qualifies as exercise. In one of my favorite studies from this year, researchers found that older women who regularly strolled about two miles a day, or a little more than 4,000 steps, lived longer than women who covered only about 2,000 steps, or a mile. Going that lone extra mile altered how long and well women lived.

　　然而，与此同时，这十年来大量的其他研究也强调，和缓的锻炼也是有意义的，即使几乎算不上是锻炼。在今年我最喜欢的研究之一中，研究人员发现，经常每天散步约两英里(相当于4000步多一点，约合3.2公里)的老年女性比每天只散步一英里(2000步)的女性寿命更长。这额外的一英里能改变女性的寿命和健康状况。

　　In fact, a recurring concern of exercise science this decade has been whether and how exercise reshapes aging, and the results generally suggest that it does — and pervasively. In various recent studies, active older people’s muscles, immune systems, blood cells and even skin appeared biologically younger, at a molecular level, than those of sedentary people.

　　事实上，近十年来，健身科学反复关注的一个问题是，运动能否及如何改变衰老过程，研究结果普遍表明，运动确实在许多方面影响衰老。在最近的各种研究中，在分子层面上，经常运动的老年人的肌肉、免疫系统、血细胞甚至皮肤的生理年龄比久坐不动的人小。