The Royal Canadian Air Force Exercise Plans are two exercise plans developed for the Royal Canadian Air Force (RCAF) by Dr. Bill Orban in the late 1950s, first published in 1961. The 5BX plan (Five Basic Exercises) was developed for men; a corresponding program was developed for women under the name XBX (Ten Basic Exercises) and the two plans were subsequently published together as one book, which was republished in 2016. The popularity of the programs in many countries around the world helped to launch modern fitness culture. History Wing Commander John Tett was appointed Special Education Officer in the RCAF in 1952. His mandate was to establish a directorate and trade for the development of physical fitness, sports and recreation. In 1956 he hired Bill Orban and directed him to devise a program which emphasized the development of a high level of fitness, but would consume only a relatively small amount of the RCAF personnel's time. The program was intended for RCAF pilots, a third of whom were not considered fit to fly at the time. While performing research at the University of Illinois in the early 1950s, Orban had noticed, when testing oxygen intake, that long periods of exercise did not necessarily lead to significant improvement. This led him to the conclusion that the intensity of exercise was more important to improving fitness than the amount of time spent on it. He incorporated this conclusion into his proposed exercise plan for the RCAF. This concept drew a negative reaction from others in the field at the time but it proved its worth in the three years of testing that the RCAF performed before releasing the program in 1961. Based on this research and testing, Orban came up with five basic exercises (5BX), four to improve flexibility and strength and one to boost aerobic fitness. The plan was innovative in two respects. Firstly, it did not require access to specialized equipment. Many RCAF pilots were located in remote bases in northern Canada, with no access to gymnasium facilities, so it was important to offer a means of keeping fit without their use. Secondly, the plan only required that eleven minutes be spent on the exercises per day. After further research and testing involving over 600 volunteers, he produced a program with ten basic exercises (XBX) for women that required twelve minutes to complete. The programs proved popular with civilians.