Experimental simulation of an airborne movement: Applicability of the bodysegment parameter estimation methods

The purpose of this study was twofold: (a) to investigate the effect of the method of body segment parameter (BSP) estimation on the accuracy of the e xperimental simulation of a complex airborne movement; and (b) to assess th e applicability of selected BSP estimation methods in the experimental simu lation. It was hypothesized that different BSP estimation methods would pro vide different simulation results. A sensitivity analysis was performed to identify the BSP items and segments responsible for the inter-method differ ences in the simulation accuracy. The applicability of the estimation metho ds was assessed based on the simulation results and the number of anthropom etric parameters required. Ten BSP estimation methods classified into 3 gro ups (4 cadaver-based, 4 gamma mass scanning-based, and 2 geometric) were em ployed in a series of experimental simulations based on 9 double-somersault -with-full-twist H-bar dismounts performed by 3 male college gymnasts. The simulated body orientation angles were compared with the corresponding obse rved orientation angles in computing the simulation errors. The inclination and twist simulation errors revealed significant (p < .05) differences amo ng the BSP estimation groups and methods. It was concluded that: (a) the me thod of BSP estimation significantly affected the simulation accuracy, and more individualized BSP estimation methods generally provided more accurate simulation results; (b) the mass items, and the lower leg and thorax/abdom en were more responsible for the intermethod differences in the simulation accuracy than other BSP items and segments, respectively; (c) the ratio met hods and the simple regression methods were preferable in simulation of the somersaulting motion due to the fewer anthropometric parameters required; (d) the geometric models and the cadaver-based stepwise regression method w ere superior to the other methods in the simulation of the complex airborne motion with twist.