The greatest thing about Eliud Kipchoge's World Record today is that his 2:01:39 marathon translates to a 12:41 5000M performance.
His 5000M PB?
12:46.53 ran in Rome on 2nd July 2004, which ranked as no. 4 all-time up until recently, when Barega and Gebrhiwet's stellar runs bumped him to no. 6 all-time.
Think about that for a moment. Over a span of 14 years, he not only managed to translate his track PB to the marathon, but he also managed to produce a much better performance over a distance 8x longer. Perhaps proof that it's possible to get better as you go into your 30s?