Athletic training involves the prevention, recognition, evaluation and care of athletic injuries. Athletic trainers are healthcare professionals who work with athletes and active individuals to help prevent, manage and rehabilitate injuries. The profession has existed since at least 129 CE but was formally recognized in 1991. To become an athletic trainer, one must complete an accredited undergraduate program, accrue clinical hours under a certified trainer, and pass both national and state exams. Athletic trainers work in a variety of settings including high schools, colleges, clinics, and professional sports organizations.