• 한국운동역학회지
• /
• 제30권3호
• /
• pp.205-215
• /
• 2020

Objective: The purpose of this study was to investigate the relative angles and cross-correlation between body segments and ski among four alpine ski turning techniques. Method: 19 alpine ski instructors participated in this study. Each skier asked to perform 4- types of turning technique, classified by radius and level. 8 inertial measurement units were used to measure orientation angle of segment and ski on the anteroposterior and vertical axis. Results: Significant differences were found between types of turning in the segments-ski relative angle on the anteroposterior and vertical axis (p<.05). Although, cross-correlation showed a high correlation between angles of segment and ski, there were significant differences between types of turning. Conclusion: Based on our results, the relative movement and timing between each segment and ski is different according to the turning techniques, so the training methods should be applied differently.

• 한국운동역학회지
• /
• 제24권4호
• /
• pp.425-433
• /
• 2014

The purpose of the study was to investigate the effect of CAD (Computer Aided Design) based alpine mono-ski bucket design on disabled ski athletes' kinematic characteristics. Two national team ski athletes with LW11 disabilities (Locomotion Winter Classification) category for sit ski participated in both pre and post experiment. Both of the subjects performed 3 trials of carved turn on a ski slope under two conditions. Where, subject "A" performed pre experiment with personal bucket and post experiment with the newly developed CAD based bucket whereas, Subject "B" as control subject performed both pre and post experiment with his personal bucket. For the experiment, 24 Infrared cameras were positioned on the ski slope which covered the path of the ski turn. Also, motion capture suit with reflective markers were worn by both subjects. In the result, decrement in medial/lateral displacement of COM, anterior/posterior displacement of COM, flexion/extension angle of trunk as well as velocity losing rate of COM was observed in subject "A" when using the newly developed CAD based bucket. In contrast, no larger effect on performance was observed when using personal buckets. In conclusion, the findings obtained from the study indicated effectiveness of newly developed CAD based bucket by reducing excessive movement of hip and trunk which is an important factor to perform an effective turn.

• 한국운동역학회지
• /
• 제27권2호
• /
• pp.91-97
• /
• 2017

Objective: To investigate rotation movement of segment for performing each position and its effect on knee/hip angulation, COM inclination, and edging angle changes. Method: Twelve Alpine skiers (age: $25.8{\pm}4.8years$, height: $173.8{\pm}5.9cm$, weight: $71.4{\pm}7.4kg$, length of career: $9.9{\pm}4.6years$) participated in this study. Each skier was asked to perform counter-rotation, neutral, and rotation positions. Results: Shank and thigh were less rotated in the counter-rotation position than in other positions, whereas the trunk and pelvis were more counter-rotated (p<.05). Hip angulation, COM inclination, and edging angle were significantly greater in the counter-rotation position than in other positions (p<.05). Conclusion: Our finding proved that the counter-rotation position increases hip angulation, COM inclination, and edging angle. Consequently, we suggest that skiers should perform counter-rotation of the trunk and pelvis relative to the ski direction in the vertical axis for the counter-rotation position. Further analysis will continue to investigate the effects of the counter-rotation position in real ski slope with kinetic analysis.

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

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

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

• 한국운동역학회지
• /
• 제26권4호
• /
• pp.361-367
• /
• 2016

Objective: The aim of this study was to compare three-dimensional kinematic changes of the lower extremity between the two different braking distances during snowplow in alpine skiing. Method: Six alpine ski instructors (age: $25.3{\pm}1.5yr$, height: $169.3{\pm}2.9cm$, weight: $66.2{\pm}5.9kg$, career: $4.2{\pm}2.9yr$) participated in this study. Each skier was asked to perform snowplow on the two different braking distances (2 and 4 m). Results: Snowplow and edging angles (p = .006 and p = .005), ankle adduction and inversion (p = .033 and p = .002), knee extension (p = .003), and hip abduction and internal rotation (p = .043 and p = .006) were significantly greater in the 2 m than in the 4 m braking distance. Conclusion: Based on our results, we suggest that skiers should make greater snowplow and edging angles on the shorter braking distance. In this situation, ankle joint adduction/inversion angle and hip joint internal-rotation make greater snowplow angle, and hip joint abduction make greater edging angle. In addition, greater knee joint extension angle may lead to more posteriorly positioned center of mass.

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

• 한국체육학회지인문사회과학편
• /
• 제57권6호
• /
• pp.293-308
• /
• 2018

본 연구는 알파인 스키와 관련하여 과거부터 최근까지 진행된 운동역학 연구의 동향을 파악하여 향후 운동역학 분야에서 진행되어야 할 연구 방향을 제언하고자 수행하였다. 운동역학 연구 분야에서는 스키 턴의 메커니즘과 스키어의 등급과 기술 수준에 따른 자세 분석, 스키와 눈의 마찰력, 공기저항 등의 연구가 주로 진행되었다. 이후 측정 센서와 컴퓨터 시뮬레이션을 활용한 연구에서는 IMU와 GPS 센서를 활용하여 스키 장비 개발 및 획득 데이터 검증에 연구가 진행되고 있다. 이와 같은 연구동향을 반영하여 추후 알파인 스키 분야에서 진행되어야 할 운동역학 연구에 대한 제언은 다음과 같다. 첫째, 기존 운동역학 분석 범위의 한계를 넘어 스키 전 구간이 분석 가능하고 스포츠 현장에서 간편하게 활용할 수 있는 측정 장비가 개발되어야 한다. 둘째, 측정 센서를 활용하여 획득한 정보의 정확도 향상과 이를 바탕으로 다양한 분석기법에 관한 연구가 지속적으로 진행되어 스포츠 현장에 도움이 될 수 있는 자료가 제공되어야 한다. 셋째, 컴퓨터 시뮬레이션을 활용하여 스키에서 발생하는 부상 메커니즘을 명확히 정립하고 부상을 예방할 수 있는 방안을 모색해야 한다. 넷째, 컴퓨터 시뮬레이션을 활용한 3차원 스키 모델을 개발하여 실제 주행데이터와 비교 검증함으로써 최적화된 스키 궤적 알고리즘 제공이 필요하다.

• 한국운동역학회지
• /
• 제27권4호
• /
• pp.257-262
• /
• 2017

Objective: This study aimed to investigate the differences in skiing time and vertical ground reaction force (vGRF) between the basic parallel turn and short turn. Method: Eleven alpine ski instructors (age: $28.73{\pm}4.29yrs$, height: $172.36{\pm}6.30cm$, body mass: $71.45{\pm}9.16kg$, career: $11.09{\pm}2.70yrs$) participated in this study. Each skier was asked to perform a basic parallel turn and short turn on a $16^{\circ}$ groomed slope. A foot pressure measurement system was used to measure the skiing time and vGRF under the three plantar regions (forefoot, midfoot, rearfoot). Results: Skiing time decreased significantly in all three phases during the short turn (p<.05). In the initiation phase, the vGRF showed a greater decrease on the midfoot and rearfoot during the short turn (p<.05). In the steering phase 1, the vGRF showed a greater increase on the forefoot and decreased on the midfoot during the short turn (p<.05). In the steering phase 2, the vGRF showed a greater increase on the forefoot and rearfoot during the short turn (p<.05). Conclusion: Our findings proved that the skiing time and vGRF changed during the short turn. Consequently, we suggest that recreational skiers should decrease the skiing time of the steering phase compared to that of the initiation phase and increase the vGRF on the forefoot and rearfoot in the steering phase.

• 한국운동역학회지
• /
• 제24권1호
• /
• pp.19-26
• /
• 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.