Adjustments to Zatsiorsky-Seluyanov's segment inertia parameters

Zatsiorsky et al. (in Contemporary Problems in Biomechanics, pp. 272-291, CRC Press, Massachusetts, 1990a) obtained, by means of a gamma-ray scanning technique, the relative body segment masses, center of mass (CM) positions, and radii of gyration for samples of college-aged Caucasian males and females. Although these data are the only available and comprehensive set of inertial parameters regarding young adult Caucasians, they have been rarely utilized for biomechanical analyses of subjects belonging to the same or a similar population. The main reason is probably that Zatsiorsky et al. used bony landmarks as reference points for locating segment CMs and defining segment lengths. Some of these landmarks were markedly distant from the joint centers currently used by most researchers as reference points. The purpose of this study was to adjust the mean relative CM positions and radii of gyration reported by Zatsiorsky et al., in order to reference them to the joint centers or other commonly used landmarks, rather than the original landmarks. The adjustments were based on a number of carefully selected sources of anthropometric data.