https://www.npr.org/sections/coronavirus-live-updates/2021/07/13/ [login to see] /no-fast-music-or-fast-running-covid-rules-in-seoul-force-gym-goers-to-slow-down
Some in South Korea may be stuck listening to slow ballads during their next high-energy workout. In an attempt to curb the spread of the coronavirus, health officials have banned fast music and even fast running at some fitness clubs.
Gyms in the capital Seoul and other nearby areas are no longer allowed to play music faster than 120 beats per minute (the speed of "Call Me Maybe" by Carly Rae Jepsen) during group fitness classes.
Treadmill speeds may not surpass 6 kilometers per hour (or 3 miles per hour).