The popular Facebook group “Aikido” shares well-written content about the traditional martial art, and the technical notebook.
Kokyunage simply means “breath throw”, indicating that it is more about rhythm and flow than about force. Still, the throws can be quite powerful.
The kokyu breath is abdominal breathing where you focus on your center (tanden).
This is the power breathing used in all budo. In aikido, it’s often called kokyu ryoku, which simply means breath power.
Kokyu actually means breathing out and breathing in. That’s how breathing is done, of course, but it also says something about how kokyunage works:
You sort of take in the attacker’s force and then return it in the throw.
You should not need to grab the attacker to be able to throw him or her in kokyunage. Instead, use the momentum of the attack for the throw, or the attacker’s commitment to a grab. Sure, that can be said about most aikido techniques, if not all of them – but it’s particularly evident in kokyunage