(FILES) An employee is at work, in the Arpin wool spinning factory in Seez, on November 9, 2017. Can technical sportswear do away with petroleum-based materials? Designers are hoping so, as they create swimming costumes from wool and trainers from whey and fruit - a challenge for sports brands faced with the imperatives of strength and safety. (Photo by JEFF PACHOUD / AFP) (Photo by JEFF PACHOUD/AFP via Getty Images)