KINETIC ANALYSES OF TWO FENCING ATTACKS – LUNGE AND FLECHE

Two fencing attacks – the lunge and the fleche – were investigated to determine the moments and powers of the joints of the lower extremity. A Vicon MX system recorded the motion while four force platforms simultaneously recorded the ground reaction forces. Inverse dynamics was used to calculate the moments and powers produced at the hip, knees and ankles of both legs. Results showed that during the lunge, the commonest attack, only the trail leg’s extensors and hip abductors contributed significantly to the attack. On the other hand, for the more dynamic and risky fleche, extensors of the ankle, knee and hip and the hip abductors for both legs contributed significantly to the attack

The effect of acceleration signal processing for head impact numeric simulations

Brain injury research in sport employs a variety of physical models equipped with accelerometers. These acceleration signals are commonly processed using filters. The purpose of this research was to determine the effect of applying filters with different cutoff frequencies to the acceleration signals used as input for finite element modelling of the brain. Signals were generated from reconstructions of concussion events from American football and ice hockey in the laboratory using a Hybrid III headform. The resulting acceleration signals were used as input for the University College Dublin Brain Trauma Model after being processed with filters. The results indicated that using a filter with a cutoff of 300 Hz or higher had little effect on the resulting strain measures. In some cases there was some effect of the filters on the peak linear (8¿30g) and rotational measures (1000¿4000 rad/s2), but little effect on the finite element strain result (approximately 2¿6 %). The short duration and high magnitude accelerations, such as the puck impact, were most affected by the cutoff frequency of different filters

Kinesiological Factors in Vertical Jump Performance: Differences Among Individuals

The purpose of this study was to investigate the kinesiological factors that distinguish good jumpers from poor ones, in an attempt to understand the critical factors in vertical jump performance (VJP). Fifty-two normal, physically active male college students each performed five maximal vertical jumps with arms akimbo. Ground reaction forces and video data were collected during the jumps. Subjects' strength was tested isometrically. Thirty-five potential predictor variables were calculated for statistical modeling by multiple-regression analysis. At the whole-body level of analysis, the best models (which included peak and average mechanical power) accounted for 88% of VJP variation (p < .0005). At the segmental level, the best models accounted for 60% of variation in VJP (p < .0005). Unexpectedly, coordination variables were not related to VJP. These data suggested that VJP was most strongly associated with the mechanical power developed during jump execution.The University of Michigan/[Rackham Predoctoral Fellowship]//Estados UniddosThe University of Michigan/[Rackham Dissertation Grant]//Estados UnidosUCR::Vicerrectoría de Docencia::Ciencias Sociales::Facultad de Educación::Escuela de Educación Físic