https://lemmygrad.ml/post/347769?scrollToComments=true
There very few good videos that explain what Systema is about, and if you do not understand it, it seems as if they are doing some weird movements. Basically, the idea behind Systema is to comprehend biomechanics and apply them to combat in order to utilise as less strength as possible. In Systema you strip the aesthetical dances of old martial arts, there are no fixed postures and it is designed in such a way that even a person (obviously it is not a guarantee) that is in physical, environmental or in a health disadvantage can win a fight.