In Aikido, circular movements or helical movements are used. These are not offensive attacks but pure defence techniques and are based on physical principles: application of lever rules, conversion of kinetic energy into rotational energy. Therefore and in contrast to other fighting techniques it is not necessary to block an attack. Instead, energy is absorbed, with own energy combined and applied for defence.
Two basic principles are used for defence: The so called Irimi (omote) means to 'tread' in an attack and to 'harmonise' with the enemy. The Tenkan principle (ura) means to turn away from the enemy and to 'harmonise' with him.
In addition to redirect the energy of an attack, the 'power of breath', in Japanese called 'kokyu', is used to amplify the own 'Ki'.
Aikido is applicable for every age, men and women. However, a good warm up and distensions are necessary because there will be strong forces onto the joints of the limbs.