A new model of the human trunk mechanics in walking

After about 15 years of “dynamical” trunk studies, too many questions stay unexplained, and too many kinematical and dynamical aspects unexplored. We know from kinematical studies that trunk amplitudes, frequencies and phases are related to velocity. But we do not know how. In addition, can these amplitudes or phases be predicted? Are the changes in the amplitudes, frequencies or phases a function of anthropometry? Or something else? Why a person has its own individual gait? Could it be possible to find objective parameters in order to describe intra- and inter-individual variations of trunk amplitudes, frequencies and phases? The present work tries to find answers to these questions from a mechanical point of view. First expanding our kinematical knowledge and relating this to anthropometry, and then introducing a new model of the human trunk mechanics in walking.