Cherie Gruenfeld is an American author of young adult fiction. She is known for writing books about sports, especially track and field and triathlon, and often incorporates her own experiences as an athlete into her stories. Gruenfeld has competed in several Ironman triathlons and marathons. Among her most well-known works are "Running Out of Time" and "Race the Wild Wind". Before dedicating herself fully to writing, she was a math and science teacher.