This paper deals with the application of the energetic macroscopic representation (EMR) for autonomy studies of an electric pedal-assisted cycle (EPAC) in mountainous terrains. Multiple slope and speed profiles from conventional cycles users are used for EPAC under different modes of electrical assistance. The results of the study show that EPAC autonomy is strongly affected by the road gradient forces in mountainous terrains: even 50% less in comparison with scenarios where road gradient forces are not considered. The use of the regenerative braking can give even an extra autonomy of 58%, depending on terrain and route conditions.