Suwari Seoi Safety: from children Dojo to High Level Competition (Biomechanical Part)

Abstract

In this paper we face the problem of safety connected to a class of throws that are more often applied in every level of competitions. However, to our knowledge it has never been a scientific study on this subject in Japan and, to our great amazement, in Europe, only one, and in very recent times. While the family of techniques that is applied with two knees on the ground has gone over time, increasing, without increasing the immediate traumas. this posed the problem if these techniques were really dangerous. It was decided to investigate in a comprehensive way, on the immediate traumas, by Biomechanics of the technique aimed at the safety of Tori, from children in the dojo up to high-level competitions. With the purpose to clarify: if the technique is dangerous, in its correct execution, for children and athletes, if the technique is dangerous for the accumulation of traumas in the long run build up a mathematical model of interaction between knees and Tatami. The experimental part was developed with a thermal imaging camera that allowed to highlight the actual impact surfaces and therefore to trace the stress received by the knees, both for the children and for the athletes of the Italian National Team. the results have made clear that, if well done and on a certified tatami, the technique has a negligible probability of immediate trauma.