• Korean Journal of Applied Biomechanics
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• v.24 no.3
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• pp.201-207
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• 2014

This study investigated the center of mass and lower extremity kinematic patterns between carved and basic paralell turn during alpine skiing. Six experienced skiers (age: $20.67{\pm}4.72yrs$, body mass: $72.67{\pm}7.15kg$, height: $171.00{\pm}5.51cm$) participated in this study. Each skier were asked to perform carved and basic paralell turn on a $22.95^{\circ}$ groomed slope. Each turn was divided into the initiation phase, steering phase 1 and 2. The results of this study show that the carved turn spent significantly less running time than basic paralell turn at all three phases (p<.05). Also vertical displacement of the center of mass was significantly greater in carved turn at all three phases, whereas inward leaning angle of the center of mass was significantly greater in carved turn at the steering phase 1 and 2 (p<.05). Bilateral knee and hip joint angle were significantly greater in basic paralell turn at the initiation phase and the steering phase 2 (p<.05). On the other hand, left knee and hip joint angle were significantly greater in basic paralell turn at the steering phase 1 (p<.05). In order to perform successful carved turn, we suggest that skiers should coordinate bilateral knee and hip joint angles to adjust the center of mass, depending on three ski turn phases.

• Journal of computational fluids engineering
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• v.21 no.3
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• pp.71-76
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• 2016

In speed skiing, aerodynamic forces play an important role in determining performance of the skier. To predict aerodynamic effects of the posture of the skier on alpine downhill skiing, we constructed equation of motion of the skier and performed the corresponding CFD simulations. Comparing drag and lift of three different skier postures, it has been shown that drag decreases significantly by tucking upper body to lower body and stretching arms forward. Also, aerodynamic lift which worked as downforce in standing posture worked upward in tuck posture, reducing friction force between snow and ski. This indicates that tuck posture have advantages over standing posture in dual mechanism, namely by reducing drag and also increasing lift. By this two-dimensional initial study we could reveal the general tendency of the aerodynamic force over the skier's body. This study not only provides a theoretical foundation for the athletes to understand the aerodynamic effects of skier postures but also shed a light on towards more accurate and rational three-dimensional CFD simulation of skiers in the near future study.

• Journal of Korean Orthopaedic Sports Medicine
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• v.3 no.1
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• pp.22-24
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• 2004

Snowboarding has become one of the premier alpine sports. The past decade has seen the popularity of snowboarding increase dramatically and the recent Winter Olympic Game showcased the strong visual appeal of the sport and the youth-oriented lifestyle and culture that accompanies it. The injury profile of the sport has also undergone change along with technological advances in boot and binding systems and the changing demographics of the sports participants. Central to the development of injury-prevention strategies is knowledge of the profile of injuries that occur, understanding those who are at particular risk and, if possible, the biomechanical factors involved in each injury type. Snowboarding was initially considered a dangerous, uncontrolled, alpine sport - an opinion based on little or no scientific evidence. That evidence has rapidly grown over the past decade and we now know that snowboard injury rates are no different to those in skiing; however, the injury profile is different. The purpose of this review is to give some perspective to the current snowboard injury literature. It discusses not only the demographic profile of those injured and the type of injuries that occur, but also gives some insight into the progress that has occurred in determining the impact of specific prevention strategies, such as splints to prevent injuries to the wrist/forearm. As the literature indicates, however, some things will not change, e.g. injuries are more likely to occur in beginners and lessons need to be reinforced as a fundamental aspect of any injury-prevention strategy.