There is provided a method of detecting a fall by a user, the method comprising detecting whether a user has potentially experienced a fall event from measurements of the movements of the user on detecting a potential fall event, determining the activity level of the user and a measure of a autonomic nervous system, ANS, response for the user associated with the potential fall event comparing the determined activity level and the measure of the ANS response to a user profile relating activity level and ANS response for the user and determining whether the potential fall event is a fall based on the result of the comparison.