Determining the location of the body׳s center of mass for different groups of physically active people.

The purpose of the present study was to compare the location of the body center of mass (CoM) determined by using a high accuracy reaction board (RB) and two different segment parameter models for motion analysis (Dempster, 1955, DEM and de Leva, 1996 adjusted from Zatsiorsky and Seluyanov, ZAT). The body CoM (expressed as percentage of the total body height) was determined from several subjects including athletes as well as physically active students and sedentary people. Some significant differences were found in the location of the body CoM between the used segment models and the reaction board method for all male subjects (n=58, 57.03±0.79%, 56.20±0.76% and 57.60±0.76% for RB, ZAT and DEM, respectively) and separately for male (n=12, RB 57.02±0.41%, ZAT 56.74±0.62%, DEM 58.19±0.60%) and female (n=12, RB 55.91±0.88%, ZAT 57.24±0.77%) students of physical activity. The ZAT model was a good match with RB for high jumpers (56.26±0.94% and 56.63±0.56%) whereas the DEM model was better for gymnasts (57.38±0.46% and 57.89±0.49%) and throwers (58.19±0.69% and 57.79±0.45%). For ice hockey players (IH) and ski jumpers (SJ) both segment models, ZAT and DEM, differed significantly from the reaction board results. The results of the present study showed that careful attention should be paid while selecting the proper model for motion analysis of different type of athletes.