If you wish to teach physical education at the elementary or secondary school level, a 4-year university undergraduate degree is usually required, such as a Bachelor of Science degree in athletic training and physical education, or a similar degree.
Within a physical education degree program, there may be various concentrations from which to choose, such as exercise science or health promotion. Once you have gained your qualifications, you will also need a teaching certificate for the level you want to teach, and be certified by the state in which you want to teach.