The U.S. Air Force, alarmed at the growing numbers of their personnel who were in poor physical shape, and being unavailable for duty because of injuries and illnesses related to this, instituted stricter standards for physical training, along with annual physical fitness tests for everyone. Failure to pass the physical fitness test would have a negative effect on promotion and re-enlistment prospects. The air force does contain a lot of people for whom excellent physical condition is a job requirement. This includes pilots (who already undergo rigorous annual physical exams) and security troops and special operations personnel. But the majority of air force personnel could get away with skipping exercise. 

The air force currently has more people trying to join, and stay in, than are needed. So the new physical fitness standards serve the dual purpose of getting more people healthy, and getting rid of those who can't make the cut. In the past, air force personnel were encouraged to exercise regularly, and the air force provided plentiful exercise facilities and sports programs. But not everyone worked out regularly. Now there are exercise sessions at least once a week. Each squadron (the basic air force unit of from a hundred to nearly a thousand airmen) has to set up a physical training program, and administer the annual fitness test. Suitably motivated, air force personnel have significantly increased the amount of physical training they engage in. The number of personnel using base fitness centers is up 30 percent since January 1st, and a lot more people can be seen running or engaging in sports on air force bases. Air force medical personnel report that the number of exercise related injuries has nearly doubled since January 1st.