The night after Zhao Yicheng defied gravity on a 15-meter climbing wall in South China's tropical Baisha county, the 15-year-old made a subtle yet symbolic gesture: changing his social media username from "Not Changing My Name Until 4.6 Seconds" to a simple set of initials.

This quiet reset followed two staggering climbs of 4.66 and 4.65 seconds in one afternoon — unofficially faster than the 4.74-second men's speed climbing world record set by American Sam Watson at last year's Paris Olympics.

"I just had to see what the view looked like from 4.6 seconds," said Zhao, steeling himself with the conviction he could match it after seeing Watson clock 4.66s in training just three days earlier.