• 한국운동역학회지
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• 제24권1호
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• pp.19-26
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• 2014

This study investigated foot pressure patterns between experienced skiers and intermediate skiers during alpine skiing. Five experienced skiers and five intermediate skiers participated in this study. Foot pressure measurement system was used to measure vertical ground reaction force (vGRF) and contact area under the six plantar regions. Each participant was asked to perform basic parallel turns and carved turns on a $18^{\circ}$ groomed slope. Each right turn was divided into the initiation phase, the steering phase 1 and 2. For the initiation phase of the basic parallel turns, significantly greater contact area was found on the LRF and RRF of the intermediate skiers (p<.05) and significantly greater vGRF was found on the LRF of the intermediate skiers (p<.05). Also significantly greater vGRF and contact area were found on the LRF and RRF of the intermediate skiers at the steering phase 1 (p<.05) and on the LRF of the intermediate skiers at the steering phase 2 (p<.05). For the carved turns, significantly greater vGRF and contact area were found on the LRF and RRF of the intermediate skiers at all three phase (p<.05). On the other hand, significantly greater vGRF was found on the RFF of the experienced skiers at the steering phase 1 (p<.05). Also significantly greater vGRF and contact area were found on the RMF of the experienced skiers at the steering phase 2 (p<.05). In order to increase performance, we suggest that the intermediate skiers should be unweighted at the initiation phase and shift the body weight to the forefoot of the outer foot at the steering phase 1. Also, the outer ski should be loaded more than the both skis at the steering phase 1 and 2.

• 한국운동역학회지
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• 제30권1호
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• pp.17-25
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• 2020

Objective: The purpose of this study is to provide a better understanding of long turn mechanism by describing long turns after kinematic analysis and provide skiers and winter sports instructors with data through which they are able to analyze right postures for turns in skiing in a systematic, rational and scientific manner. Method: For this, a mean difference of kinematic variables (the center of gravity (CG) displacement of distance, trajectory, velocity, angle) was verified against a total of 12 skiers (skilled and unskilled, 6 persons each), regarding motions from the up-start to down-end points for long turns. Results: First, concerning the horizontal displacement of CG during a turn in skiing, skilled skiers were positioned on the right side at the upstart and edge-change points at a long turn. There was no difference in anteroposterior and vertical displacements. Second, in terms of CG-trajectory differences, skilled skiers revealed a significant difference during a long turn. Third, regarding skiing velocity, skilled skiers were fast at the edge-change and maximum inclination points in long turns. Fourth, there was no difference in a hip joint in terms of a lower limb joint angle. In a knee joint, a large angle was found at the up-start point among skilled skiers when they made a long turn. Conclusion: In overall, when skilled and unskilled skiers were compared, to make a good turn, it is required to turn according to the radius of turn by reducing weight, concerning the CG displacement. Regarding the CG-trajectory differences, the edge angle should be adjusted via proper inclination angulation. In addition, a skier should be more leaned toward the inside of a turn when they make a long turn. In terms of skiing velocity, it is needed to reduce friction on snow through the edging and pivoting of the radius or turn according to curvature and controlling ski pressure. Regarding a lower limb joint angle, it is important to make an up move by increasing ankle and knee angles instead of keeping the upper body straight during an up motion.

• 한국운동역학회지
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• 제20권3호
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• pp.319-325
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• 2010

The purpose of this research was to investigate the differences in the ski carving turn motion according to level of expertise. The posture and movement of 6 skiers nearby the fall-line was evaluated with a biomechanical approach focusing the rotational mechanics. The slope was at an angle of $9^{\circ}$ and the following variables were measured and calculated: tangential velocity, change of COM height after passing fall-line, width between feet, angle between upper body and thigh, trunk angle, average radius of curvature and average centripetal force. The expert skiers minimized their center of mass height movement and maintained the width of between their feet after the passing the fall-line in comparison with the beginners and intermediate skiers. The experts restrained themselves from pushing their upper body downward after the turn to maximize the centripetal force. The experts in comparison with the beginners and intermediate skiers during the turn didn't have to reduce their radius of curvature to maintain a high centripetal force. It was concluded, that the most important factor affecting the centripetal force, was for the beginners and intermediate skiers, to minimize their movement while using the appropriate amount of edging.

• 한국운동역학회지
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• 제29권4호
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• pp.219-226
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• 2019

Objective: The purpose of this study is to provide a better understanding of short turn mechanism by describing short turns after kinematic analysis and provide skiers and winter sports instructors with data through which they are able to analyze right postures for turns in skiing in a systematic, rational and scientific manner. Method: For this, a mean difference of kinematic variables (ski-hip angle, ski-shoulder twist angle, pole checking angle, the center of gravity (CG) displacement, trunk forward lean angle) was verified against a total of 12 skiers (skilled and unskilled, 6 persons each), regarding motions from the up-start to down-end points for short turns. Results: There was no difference in a ski-hip twist angle. The ski-shoulder twist angle was large at the up-start point while a pole-checking angle was high at the down-end point in skilled skiers. Concerning the horizontal displacement of CG, skilled skiers were positioned on the right side at the upstart point. No significant difference was observed in the trunk forward lean angle. Conclusion: According to the ski-shoulder twist angle and CG horizontal displacement results, the upper body should be kept leant toward the pole. In addition, big turns should be made via edging and angulation. During pole checking, the hand holding the pole should be thrown and released toward a vector direction of the forearm.

• 대한의용생체공학회:의공학회지
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• 제35권3호
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• pp.35-41
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• 2014

In this study, joint angles of the lower extremity and inertial sensor data such as accelerations and angular velocities were measured during a ski simulator exercise in order to evaluate the skill of skiers. Twenty experts and twenty unskilled skiers were recruited for the study. All expert skiers held the certificates issued by the Korea Ski Instructors Association. A three-dimensional motion capture system and two inertial sensors were used to acquire joint movements, heel acceleration and heel angular velocity during ski simulator exercises. Pattern variation values were calculated to assess the variations in ski simulator motion of expert and unskilled skiers. Integral ratio of roll angular velocity was calculated to determine the parallel alignment of the two feet. Results showed that ski experts showed greater range of motion of joint angle, peak-to-peak amplitude(PPA) of heel acceleration and PPA of heel angular velocity than unskilled skiers. Ski experts showed smaller pattern variations than unskilled skiers. In addition, the integral ratio of roll angular velocity in ski experts was closer to 1. Inertial sensor data measurements during the ski simulator exercises could be useful to evaluate the skill of the skier.

• Journal of Trauma and Injury
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• 제21권1호
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• pp.53-58
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• 2008

Purpose: Skiing and snowboarding are becoming increasingly popular. Accordingly, the incidences of injuries among skiers and snowboarders are also increasing. The purpose of this study was to investigate the injury patterns of and the contributing factors to head injuries of skiers and snowboarders and to evaluate the differences in characteristics between skiing and snowboarding head injuries. Methods: One-hundred patients who visited the emergency department of Wonju Christian Hospital between January 2005 and March 2007 due to head injuries from skiing and snowboarding were enrolled. The mechanisms and the histories of the injuries were investigated by surveying the patients, and the degrees of head injuries were estimated by using brain CT and the Glasgow Coma Scale. The degrees and the characteristics of brain injuries were also analyzed and compared between skiers and snowboarders. Results: Out of 100 patients, 39 were injured by skiing, and 61 were injured by snowboarding. The mean age of the skiers was $26.7{\pm}10.0$, and that of the snowboarders was $26.7{\pm}6.2$. The percentage of male skiers was 43.6%, and that of snowboarders was 63.9%. The most frequent initial chief complaints of head-injured skiers and snowboarders were headache and mental change. The most common mechanism of injuries was a slip down. The mean Abbreviated Injury Scale Score (AIS score) of the skier group was $4.5{\pm}2.1$ and that of the snowboarder group was $5.9{\pm}5.0$ (p=0.222). The percentage of helmet users was 7.1% among skiers and 20.8% among snowboarders (p=0.346). Head injuries were composed of cerebral concussion (92.0%) and intracranial hemorrhage (8.0%). Intracranial hemorrhage was most frequently caused by falling down (62.5%). Conclusion: The most common type of head injury to skiers and snowboarders was cerebral concussion, and severe damage was usually caused by jumping and falling down. No differences in the characteristics of the head injuries existed between skiing and snowboarding injuries.

• 한국운동역학회지
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• 제21권3호
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• pp.259-268
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• 2011

This study aimed to examine the kinematic characteristics of the national elite cross-country skiers' double poling technique and to provide the quantitative data for better performance. Four male elite cross-country roller skiers skied maximum velocity with Double Pole technique. The cycle characteristics with angles of elbow, hip, and knee joint were analyzed. The results showed that CM velocity of the body was increased with the third cycle, the cycle time and length were also increased. The poling time and recovery time rate showed with 32.79%, 67.44% respectively. The joint angles with elbow, hip and knee were $106^{\circ}$, $133.14^{\circ}$ $156.87^{\circ}$ at pole in event, $158.94^{\circ}$, $65.7^{\circ}$, $140.19^{\circ}$ at pole out event. Elite skiers should decrease double poling time rate and increase recovery time rate in order to improve the double poling performance. The cycle length and velocity of the double poling should be increased for the better performance. The elbow angle should be minimized at pole in event with maximum extension until pole out event. The hip and knee angles should be increased for the recovery phase.

• 한국콘텐츠학회논문지
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• 제13권7호
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• pp.386-394
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• 2013

본 연구는 스키 참가자들의 여가제약 협상 수준에 따른 레크리에이션 전문화의 차이와 여가제약 협상이 레크리에이션 전문화에 미치는 영향을 규명하는데 그 목적이 있다. 경기도와 강원도에 위치한 4개 스키리조트를 방문하는 18세 이상의 성인 남녀를 모집단으로 설정하였고, 군집표집법을 이용하여 표본을 추출하였다. 총 400부의 설문지를 배포하였고 374부가 최종분석에 활용되었다. 여가제약 협상전략을 활용하는 참여자는 강도와 정도에 따라 3개의 집단으로 분류하였고 여가제약 협상 수준에 따른 레크리에이션 전문화의 하위요인별로 일원변량분석과 회귀분석을 실시하여 다음과 같은 결론을 도출하였다. 첫째, 여가제약 협상은 전략을 활용하는 강도와 정도에 따라 상, 중, 하의 3단계로 분류가 되었다. 둘째, 여가제약 협상 수준에 따른 레크리에이션 전문화는 전체평균에서 차이가 나타났으며, 여가제약 협상전략을 적극적으로 활용하는 집단이 그렇지 않은 집단에 비해 과거경험, 인생의 구심성, 경제적 투자 등의 전문화 하위요인에서 높은 평균을 나타냈다. 셋째, 여가제약 협상전략의 적극적인 활용은 레크리에이션 전문화에 정적 영향을 미치는 것으로 나타났다.

• 대한정형외과스포츠의학회지
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• 제2권2호
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• pp.153-157
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• 2003

목적: 이 연구의 목적은 스키손상의 특징 및 경향을 검토하여 안전사고를 예방할 수 있는 프로그램과 보호 장비의 개발 및 사용 등에 참고가 되기 위해서이다 대상 및 방법: 1998년부터 2001년까지 한국 강원도의 한 스키 리조트에서 스키를 타다가 부상당하여 응급치료를 받은 사람들을 대상으로 설문조사하였다. 부상이란 alpine 스키 를 타던 도중에 어떤 형태의 사고로 인하여 의무실에서 의학적 치료를 필요로 했던 경우로 정의 하였다 수상을 입은 모든 스키어들은 그들의 손상 기전, 스키 실력, 스키 슬로프의 난이도등을 기입하는 설문지를 작성토록 하였다. 결과:3년간에 걸쳐 총 119명이 응급치료를 받았다. 스키 손상의 발생 빈도는 1000명당 6.4명 이었다. 스키손상은 남자가 여자보다 약간 많았으며 연령은 주로 20대였고 스키수준이 낮을수록, 난이도가 낮은 슬로프일수록 높았고, 손상형태는 염좌 및 인대손상이 가장 많았다 손상부위는 슬관절 부위가 전체의 30$\%$를 차지하였다. 결론: 스키손상은 다른 나라의 보고에 비해 여전히 증가된 경향을 보였는데 이는 스키장 안전관리 미흡 내장객수 과다. 스키 사용자의 상식 및 교육미숙 등이 중요한 원인적 요인으로 작용한다고 생각된다

• 대한정형외과스포츠의학회지
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• 제1권2호
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• pp.109-114
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• 2002

역사적으로알파인스키부상은스키장비의발달과밀접한관련을가지고변화하여왔다. 근래에일어난스키장비의혁명으로인하여스키부상은또다른양상으로바뀌어가고있는추세이다. 현대적인스키, 스키화, 바인딩의개발로과거에빈발하던경골간부골절이나족관절손상은1970년대말에이르러90$\%$ 가까이감소하였다. 하지만1980년대에들어서전방십자인대손상을포함한심한슬관절손상은 약3배가까이증가하였으며,장비의개발에도불구하고전방십자인대손상을줄이지못하고있다. 최근에는슬관절이하의하지손상및전방삽자인대손상발생율모두변화가중단된상태이다. 최근스키디자인을완전히바꾸어놓은카빙스키는전통스키에비하여상급자에게전방십자인대단독손상의위험성을증가시키는것으로보인다. 대신초급자에게는족관절손상의위험성이높다. 스키로인한하지손상율을더욱낮추기위해서는스키전문점의스키기술자가ASTM (American Society for TestingMaterial)의표준에따라장비를관리하도록유도하여야한다. 현재까지개발된스키장비중전방십자인대손상을줄일수있는것으로검증된것은없다. 효과가입증된유일한방법은,위험한상황을인식하여그것을피하는방법을익히는트레이닝프로그램뿐이다.