You've got 4 years to go till your biological peak, after 30 testoterone production diminshes. Endurance goes up with age if you keep training. The best long d

You've got 4 years to go till your biological peak, after 30 testoterone production diminshes. Endurance goes up with age if you keep training. The best long distance runners, the Tarahumara, got brought to races. The first they didn't do well because they were forced to wear the shoes of the sponsor. The second time they could run barefoot like they used to, in a cutout from an old tire with a cord pulled through. The 60 year old won handily. Source: Born To Run by Chris McDougall. Highly recommended, devoured it.