The invention relates to a method and apparatus for determining a respiration of a subject (305) in which with a single multi-axial accelerometer (310) positioned on a body of the subject (305) accelerometer signals are generated (101) indicative of the acceleration of the subject (305) along different spatial axes a vector magnitude signal of the acceleration of the subject (305) along the different spatial axes is calculated (102) from the accelerometer signals a non-respiratory motion contribution to the acceleration along the different spatial axes is identified (103 203) from the vector magnitude signal which non-respiratory motion contribution is not caused by the respiration and a respiration signal indicative of the respiration of the subject is determined (104 204) by filtering the non- respiratory motion contribution from at least one of the accelerometer signals. Fig.9
