translation.en: And what they found is that, if you start running the marathon at age 19, you will get progressively faster, year by year, until you reach your peak at age 27.
translation.zh: 他们的发现 是，如果在19岁开始跑马拉松， 你将逐渐跑得越来越快，逐年增加， 直到在27岁时到达顶峰。