The phenomenology of inertial kinematics in the structure of forming motor adaptations

The aim of the study was to develop a methodology for assessing the state of motor adaptation at the level of the main joint elements of the locomotor system when performing postural deviations with inertial components in a group of healthy volunteers (n=24). To conduct the study we used the “Teslasuit” smart suit as a technology with a system of inertial measuring units. A virtual skeletal model of the subject’s body was reconstructed on the obtained quaternions for each direction of spatial displacement. Parameters of inertial kinematic were calculated by the Fast Fourier Transform in the frequency bands of 0.1–5, 6–10, and 11–15 Hz. To assess motor adaptive reactions, we developed the following tests: ventrodorsal displacement test; laterolateral displacement test; linear displacement test in vertical direction; axial rotation test around vertical. All test tasks were performed using biofeedback as a virtual reality environment. The study revealed the presence of universal motor adaptation mechanisms with activation of the components of axial rotation of the trunk and axial rotation and flexion of the leading shoulder joint. At the same time, a dynamic phase of postural regulation during axial rotations and tilts of the body leads to the activation of motor adaptation mechanisms from the leading hip, knee, and ankle joints, while axial movements form a picture of the kinematic stabilization of these locomotor system elements.

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