Career
He is also known as J. P. Muller. His book Mit System (My System), published in 1904, was a bestseller and has been translated to English and many other languages. My System explains Müller"s philosophy of health and provides guidelines for the 18 exercises that comprise the system.
Much of what was stated in his system has since been accepted by the medical community, with many of his basic movements being used in modern-day physical therapy and rehabilitation.
The emphasis on body-weight exercise and the use of dynamic stretching is useful for many people, and has been found appropriate in a wide range of patients. Müller was appointed Knight of the Dannebrog in 1919.