This paper deals with the motion analysis of carving turns in snowboarding by the measurement of reaction force from snow surface. The measurement system of reaction force from snow surface is installed between the snowboard and bindings, and the system can measure the 6-axis force components from snow surface (force and moment) using the outputs of several 3-axis compact force sensors. We conducted the measurement experiment of carving turns performed by a high skill snowboarder. The results showed how the reaction force from snow surface varied from sec to sec. Furthermore, we compared the results of this study and the previous study and we calculated the moments of torsion and deflection of snowboard for denoting the important factors in carving turns. The results showed the differences of reaction forces according to the difference of the snowboarder’ s skill and the deflection moment of the snowboard for the unweighting and the adjustment of turn. The results can be used to clarify the mechanism of snowboard turns and to evaluate the snowboarder’ s skill.
