Aikido is a modern Japanese martial art with deep roots in  traditional Japanese fighting arts, either empty-handed or  with weapons. It evolved into non-violence, becoming a non-  competitive martial art with the objective of self-improvement. Aikido is an effective martial art, blending with the force of the opponent without being destructive and, as such, is  used by law enforcement agencies in Japan and many other  countries. Aikido is categorised as a demonstration martial art  by alternating attacks and defences. The sport does not have  gender or weight classifications.