When Karly Tardiff parked her bike before heading into work in Winnipeg, Manitoba, on August 13, she wasn’t expecting to do sprints until her CrossFit class later that afternoon. After all, the 28-year-old fundraising professional—who is the co-leader of a local Winnipeg running club called the Badass Lady Gang and trains for 5Ks and half marathons—was wearing a sundress and wedges, with her workout gear packed for later. “I commute to work every day, and then I bike off to CrossFit,” she told Runner’s World. Shortly after her lunch break, though, Tardiff’s normal routine was interrupted by a frantic maintenance...