Replayed of Faith Kipyegon's attempt to day to break the 4-minute mile (with Nike pulling out all the stops to help her)

The effort included developing a 3D printed sports bra using "FlyWeb":

some wearers reported being able to feel airflow on the chest for the first time while running, a sensation made possible by the garment’s open, breathable zones. “Most women have never experienced that while running,” she said. “We don’t even think about it because it’s just not something we’ve ever expected to feel.”