Kinesiology, Vol. 40 No. 2., 2008.
Original scientific paper
Ground reaction forces in performance of steps in step aerobics at varying heights of step bench
Maja Horvatin-Fučkar
; Faculty of Kinesiology, University of Zagreb, Croatia
Mladen Mejovšek
; Faculty of Kinesiology, University of Zagreb, Croatia
Kamenka Živčić Marković
; Faculty of Kinesiology, University of Zagreb, Croatia
Abstract
Kinetic parameters of ground reaction force were analysed during step exercises of stepping on and off a step bench in order to determine the predictive biomechanical performance indicators for fundamental steps in step aerobics (basic step, step touch) at varying heights of the step bench. Nine subjects, professional step aerobics instructors, agreed to participate in this study (four males, five females). On the basis of the ground reaction force, the basic statistical parameters of the following components were calculated: Fx (mediolateral), Fy (anteroposterior) and Fz (vertical). The data were subsequently processed using nonparametric statistics for the dependent samples. More specifically, the Wilcoxon matched pairs test was used in order to calculate the differences in performances of identical steps at varying bench heights and in performances of various steps at identical bench heights. Statistically significant differences in Fx, Fy and Fz were obtained depending on two factors. The first factor consisted of the specifics of the technique used for the complete (basic step) or partial (step touch) transfer of body weight from one leg to the other. The second factor was the overall amplitude of body movement as each single step was being performed at varying heights and following increases in bench height (15, 20 and 25 cm), which thereby increased the overall intensity of performance.
Keywords
step aerobics; ground reaction force (GRF); aerobics instructors; Wilcoxon non-parametric matched pairs test; step touch; basic step
Hrčak ID:
30819
URI
Publication date:
30.12.2008.
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