Florence P. and Henry O. Kendall were pioneers in research in the field of physical therapy, conducting groundbreaking research at the height of the polio epidemic to establish baselines for normal function in children and young adults. They believed that no modern PT should treat “abnormal” conditions without knowing what “normal” is, and their research helped establish what constitutes “normal” function in a patient. Their research was subsequently incorporated into their book, “Muscles Testing and Function,” which became the standard text in its field. By 2005 the publication had seen five U.S. and seven foreign-language editions.