Olympic competitors over 40 are inspiring — and less of a rarity than they used to be.

Scientists say athletes with extreme staying power may be that way due to molecular-level advantages. Studying those could further the quest to understand and slow down the ravages of human aging.

In Paris, the very oldest competitors showed up in the shooting, table tennis and equestrian events. And there were middle-aged folks in golf, beach volleyball, cycling, sailing, rowing and fencing — not to mention skateboarding, where Andy Macdonald, a 51-year-old dad in cargo pants and graying 49-year-old legend, Dallas Oberholzer, held the crowd spellbound. They all notched clear victories over ageist stereotypes — and maybe even time itself.