Alpine Skiing Research Articles

Mass point versus whole-body modeling of skiers for performance evaluation in alpine skiing.

The altitude differential of the specific mechanical energy, , is used to evaluate skiing performance. It is defined as the negative differential between the skier's total specific mechanical energy ( ) and the altitude of the skier's center of mass (COM). Till now, was obtained upon a mass-point (MP) model of the skier's COM, which neither considered the segmental energies of their relative movements to the COM, nor their rotational kinetic energies. The aims of the study were therefore: (a) to examine the deviations in between the MP and a more complex linked segment (LS) skier model consisting of 15 rigid bodies, which encountered the aforementioned defectiveness, (b) to compare the energy fluctuations of the two skier models, and (c) to investigate the influence of the gate setup on (a) and (b) in giant slalom. Three-dimensional whole-body kinematics of nine skiers was measured using a global navigation satellite system and an inertial motion capture system while skiing on a predefined course divided into a turny and open gate setup. Mechanical energies including their altitude differentials were calculated for the LS and MP models. There were no significant differences in and ski turn averages, as in individual data points, between both skier models for both analyzed gate setups. The energies additionally considered by the LS model presented a negligible part regardless of the gate setup. In conclusion, the MP skier model is sufficiently accurate for the evaluation of the skiing performance with .

Differences Between Traditional and Modern Technology in the Acquisition of New Ski Knowledge

Purpose: Video materials have been used as teaching tools for many years. With the development of modern technology, new video devices have appeared that have greatly improved the quality and capabilities of video materials. This study was conducted with the purpose of investigating and comparing the current traditional and modern ways of recording ski elements. In the traditional way of recording, the cameraman stands on the ski slope and uses a camera to record a demonstration of the ski element of the skier moving toward him. On the other hand, the modern way of recording was made with the Gopro 360 max, which allows you to record video while skiing.
 Methods: The sample of respondents who evaluated the quality of the traditional and the Gopro 360 max videos for three skiing elements consisted of 149 students (105 male and 44 female) from the Faculty of Kinesiology Osijek. Prior to the video quality assessment test, the performance of the ski elements was explained to the students using traditional and modern video footage. When solving the ski knowledge test, students had the opportunity to watch and use traditional and/or modern videos.
 Results: The average score that students achieved on the ski knowledge test was 8.9 ± 2.48 points (74.16 ± 0.21%). When evaluating the quality and contribution of the videos, students rated the usefulness of the traditional method of video recording with an average score of 3.01 ± 1.25, while the modern method of video recording received an average usefulness score of 3.79 ± 1.07. The difference between the traditional and modern video recording was statistically significant at the p < 0.01 level.
 Conclusion: The obtained results indicate that the way the Gopro360 max records and presents the skiing elements contributes significantly to the quality of the presentation and the acquisition of specific skiing knowledge compared to the traditional recording method.
 Keywords: Gopro360 max, ski elements, knowledge test

Accurate Extraction of Cableways Based on the LS-PCA Combination Analysis Method

In order to maintain a ski resort efficiently, regular inspections of the cableways are essential. However, there are some difficulties in discovering and observing the cable car cableways in the ski resort. This paper proposes a high-precision segmentation and extraction method based on the 3D laser point cloud data collected by airborne lidar to address these problems. In this method, first, an elevation filtering algorithm is used to remove ground points and low-height vegetation, followed by preliminary segmentation of the cableway using the spatial distribution characteristics of the point cloud. The ropeway segmentation and extraction are then completed using the least squares-principal component combination analysis method for parameter fitting. Additionally, we selected three samples of data from the National Alpine Ski Center to be used as test objects. The real value is determined by the number of point clouds manually deducted by CloudCompare. The extraction accuracy is defined as the ratio of the number of point clouds extracted by the algorithm to the number of point clouds manually extracted. While the environmental complexities of the samples differ, the algorithm proposed in this paper is capable of segmenting and extracting cableways with great accuracy, achieving a comprehensive and effective extraction accuracy rate of 90.59%, which is sufficient to meet the project’s requirements.

Switzerland? The Best Choice for Accommodation in Europe for Skiing in the 2023 Season

The study investigates the connections between tourists‘ hotel preferences and distance from resort expressed in meters, distance from ski lift expressed in meters, booking score, number of reviews, room type, feature of free cancellation, price expressed in Euro, type (private host/hotel), destination (ski-to-door access/travel sustainable property) from 10 highly appreciated European ski locations offered in from February 2023 by Booking, using a sustainable, electronic instrument for collecting and analyzing a large amount of data, Octoparse 8 and a multi-attribute decision model. Previous studies concerning tourist preferences and online behavior used traditional methods, such as questionnaires and surveys, being limited to a certain number of questions and respondents; thus, this study covers a research gap in the literature with regard to the use of a large amount of data, electronic instruments and multi-attribute models to rank the hotel locations, which derives from the difficulty in obtaining the necessary data to carry out an in-depth analysis. The results show that when selecting a hotel location from an exclusive ski resort, the tourists are interested in the number of reviews, the price and the distances from the resorts to the ski slopes, while the booking score is less important. This is translated into practical implications for marketers and hotel managers, presented at the end of the paper.

Coefficient of Difficulty in Running a Sports Course in Alpine Skiing

In alpine ski disciplines, it is common for competitors to record incomplete runs. In some instances, up to 40% of competitors have failed to complete a course. Possible reasons include incorrect preparation of skiers (lack of adequate motor preparation) and poor tactical approaches. However, there are also some errors in the setting of gates on a course. The aim of this paper is to determine the objective difficulty coefficient of alpine skiing competition courses, based on course geometry and the kinematic parameters of the run. This research monitored alpine skiers during the FIS World Cup. All four alpine skiing disciplines (i.e., downhill, super giant, giant slalom, and slalom) were considered. The average value of the coefficient of difficulty (W.tr) was the highest for the downhill style runs and amounted to 1.20, the super giant and the giant had comparable values of 1.13–1.14, and for the slalom, the W.tr value was the lowest at 0.97. Based on the determined coefficients of route difficulty, it is possible to derive a quantifiable metric to estimate the degree of risk associated with different sections of a course.

Study on Wind-Proof Effect and Stability of Windbreak Fence in Alpine Skiing Center

As a venue for the 2022 Winter Olympic and Paralympic Games, the National Alpine Skiing Center is located on Xiaohaitou Mountain in Beijing’s Yanqing district, where strong winds occur frequently. To reduce the impact of strong winds on the competition, windbreak fences have been installed in the ski area. To determine the effect and stability of the windbreak fences beside the ski slope of the alpine skiing center, the numerical simulation method was used to study the performance of 3.7 m, 4.7 m and 7.9 m high wind barriers. According to the actual meteorological conditions, two kinds of inlet wind speeds of 10 m/s and 33 m/s were set. The results show that the ambient wind speed is maximum only in a small area near the opening through the windbreak fence. When the ambient wind speed is 10 and 33 m/s, the wind speed in most drainage areas behind the barrier is below 5 and 15 m/s, respectively, which is significantly lower than the wind speed of incoming flow, and the wind protection effect is obvious. When the wind speed at the entrance height is 10 m and 33 m/s, the wind-proof effect is obvious. The wind-proof effect of 7.9 m high windproof bars is better than that of 3.7 and 4.7 m high windproof bars. The wind pressure at the top of the fence is the highest, and the wind pressure also increases when the wind speed increases. Under the action of maximum wind speed, the stability of a 7.9 m high storm fence is low.

Alpine skis categorization with comprehensive decision tree models

Alpine skis categorization with comprehensive decision tree models

Biodiversità, Alpi, Architettura. Esperienze dal premio Constructive Alps

Due to their geographical, orographic, cultural, and historical characteristics, the Alps can be considered a vast park, representing a reservoir of biological diversity in the centre of Europe; however, such biodiversity is at serious risk. The Alps are breath-taking in their nature, with their peaks, trees, water, animals, insects, people and languages, as well as in their impressing architecture made of the same materials as forests and rocks. On the other hand, the Alps currently count 120 million tourists a year, they are compromised by industries, motorways, cities, consumption, their forests are broken up by ski slopes and ski lifts, their glaciers are disappearing, and the valley floors are exploited down to the last usable metre. In the Alps, the climate crisis is not just any emergency, but the main crisis determining all the others. In this fragile environment, the Constructive Alps award is an established reality in the panorama of research on contemporary Alpine architecture. Since 2010, Constructive Alps has been investigating environmentally aware contemporary Alpine architecture, the only viable architecture there. Over the years, a large number of the approximately 2000 realized works proposed by designers and clients have proved to be attentive to the dialogue with the natural context and the biodiversity of places. Those projects can realistically constitute an atlas of virtuous places, a rich catalogue of good practices, and an articulate handbook of solutions and techniques. The essay begins with a glossary that enunciates the concepts of “biodiversity”, “Alps”, “architecture”, and “Constructive Alps” and then recounts four projects selected by the award jury that stand out for their stimulating interpretations of the relationship between architecture and the environment.

Single-leg stance on a challenging surface can enhance cortical activation in the right hemisphere – A case study

Maintaining body balance, whether static or dynamic, is critical in performing everyday activities and developing and optimizing basic motor skills. This study investigates how a professional alpine skier's brain activates on the contralateral side during a single-leg stance. Continuous-wave functional near-infrared spectroscopy (fNIRS) signals were recorded with sixteen sources and detectors over the motor cortex to investigate brain hemodynamics. Three different tasks were performed: barefooted walk (BFW), right-leg stance (RLS), and left-leg stance (LLS). The signal processing pipeline includes channel rejection, the conversation of raw intensities into hemoglobin concentration changes using modified Beer-Lambert law, baseline zero-adjustments, z-normalization, and temporal filtration. The hemodynamic brain signal was estimated using a general linear model with a 2-gamma function. Measured activations (t-values) with p-value <0.05 were only considered as statistically significant active channels. Compared to all other conditions, BFW has the lowest brain activation. LLS is associated with more contralateral brain activation than RLS. During LLS, higher brain activation was observed across all brain regions. The right hemisphere has comparatively more activated regions-of-interest. Higher ΔHbO demands in the dorsolateral prefrontal, pre-motor, supplementary motor cortex, and primary motor cortex were observed in the right hemisphere relative to the left which explains higher energy demands for balancing during LLS. Broca's temporal lobe was also activated during both LLS and RLS. Comparing the results with BFW– which is considered the most realistic walking condition–, it is concluded that higher demands of ΔHbO predict higher motor control demands for balancing. The participant struggled with balance during the LLS, showing higher ΔHbO in both hemispheres compared to two other conditions, which indicates the higher requirement for motor control to maintain balance. A post-physiotherapy exercise program is expected to improve balance during LLS, leading to fewer changes to ΔHbO.

ANALYSIS OF GEOMORPHOLOGICAL CHARACTERISTICS OF SKIING TRACKS FOR TOURISTIC POTENTIAL EVALUATION OF UKRAINIAN CARPATHIANS

The aim of the paper is to evaluate the quality of skiing tracks in the Ukrainian Carpathians. To do this we suppose to define a set of geomorphological characteristics of skiing tracks and determine theirs influence value on the tracks specialization and its suitability for skiing, also assess the touristic potential of the ski resorts of the Ukrainian Carpathians.&#x0D; Methods and approaches of research borrowed from a similar study on the avalanches danger estimation of other ski resorts. We obtained a number of geomorphological characteristics of the tracks and visually estimated the quality of its bed using created lengthwise and cross-section profiles of skiing slopes using a digital relief model. The visual analysis identified the areas for braking, as well as significant inequalities, protracted areas and track parts with inversed inclination which make worse the quality of the skiing and is danger the skiers.&#x0D; So the main research method is the cartographic modeling. We selected 7 ski resorts located in different parts of the Ukrainian Carpathians. The profiles were created using free Geographic Information System QGIS and open geospatial data of radar survey of the Earth's surface (SRTM and ASTER GDEM). We also compared received results with foreign similar studies. Scientific novelty. There are defined the set of geomorphological characteristics of a ski slope in the article. There are the length of the track (or its horizontal projection), the level difference and the derivative characteristic is the steepness of the slope (as well as its maximum and minimum values). This list was supplemented by cross-section profiles description (it may be convex, bent, flat or inclined). Altogether we compared 24 tracks of the Ukrainian Carpathians. There are created lengthwise and cross-section profiles for each of them and all results put into a table presented in the article.&#x0D; Practical results. We made a conclusion that the skiing slopes of the Ukrainian Carpathians have similar geomorphological characteristics in most cases. The average slope of the tracks is 9.5°. The maximum value is 13° and the minimum is about 3°. The length of the tracks varies from 1 to 4 km and the length of majority of them is not excites of 1.8 km. The height difference is from 50 m to 550 m, the average mean is 315 m, which is not quite long. The configurations of the most horizontal profiles are convex or even, which is not optimal for skiing. In addition, the presence of hills makes “blind zones” which limit the visibility of the track and can cause a collision of skiers. Most of skiing track beds has convex cross-section profiles or they are significantly declined, which is also not an advantage.&#x0D; Based on the received metric values we defined the weak and strong sides of the national resorts. The ski slopes haven’t many complexity categories and are interesting for amateur skiers. Therefore the national resorts give way to foreign ones even located in the Carpathians which have a greater variety and more levels of complexity of tracks. This circumstance can be an obstacle to maintenance of tracks and increase requirements for corresponding equipment. So national skiing resorts should focus on pricing policies and territorial accessibility.

An Innovative Compact System to Measure Skiing Ground Reaction Forces and Flexural Angles of Alpine and Touring Ski Boots.

Skiing is a popular winter activity spanning various subdisciplines. Key hardware are ski boots, bindings, and skis, which are designed to withstand loads generated during skiing. Obtaining service forces and moments has always been challenging to researchers in the past. The goal of the present study is to develop and test a lightweight and compact measurement system to obtain the Ground Reaction Forces and the kinematics for ski touring and alpine ski. To do so, we adapted two six-axis load cells to fit into ski touring and alpine skis adding 20 mm height and 500 g weight to the original ski. To measure kinematics, we created custom angular sensors from rotary potentiometers. The system was tested indoors using a force platform and motion capture system before a first set of field tests in which the sensors were used to measure ski touring and alpine skis kinetics and kinematics. Validation trials showed maximum errors of 10% for kinetics and 5% for kinematics. Field tests showed data in agreement with previous findings on the topic. The results of this study show the possibility of using our system to study biomechanics and equipment performances for ski touring, alpine skiing, and possibly other disciplines.

Impact of Construction and Functioning of a Newly Built Ski Slope on the Quality of Nearby Stream Water

The construction of new, artificially snowed, ski slopes and the accompanying infrastructure changes the natural environment and exerts pressure on the ecosystems. This study examined the impact of the construction and operation of a new ski slope, with its infrastructure and artificial snow production, on the quality of nearby stream waters. The research period covered the time before, during and after the slope construction. Electrolytic conductivity (EC) and pH were measured on-site, chemical analyses included the determination of Ca2+, Mg2+, Na+, K+, HCO3−, SO42−, Cl−, NO3−, and microbiological analysis comprised mesophilic and psychrophilic bacteria, total and fecal coliforms, and E. coli. As a result of intensive environmental transformations, the examined parameters varied significantly over the study period, as shown by the coefficient of variation. Due to land cover changes, concentrations of all the examined parameters increased during the ski slope construction due to ions and bacteria leaching from the soil. However, when construction works were finished, all bacterial and some chemical indicators returned to the state observed before the construction, most probably due to the recovery of vegetation and self-purification of water. Supply of melt water from artificial snow, produced from water containing higher concentrations of ions, increased pH, EC, Ca2+, Mg2+ and HCO3− in the stream. Providing that the development of ski stations is unavoidable in the considered region, conducting studies assessing the impact of new ski slope construction is an important step that should be conducted prior to undertaking such investments.

Potential estimation model in French alpine skiing - Individual evolution curve and progression typology.

Estimating the potential of alpine skiers is an unresolved question, especially because of the complexity of sports performance. We developed a potential estimation model based solely on the evolution of performance as a function of age. A bayesian mixed model allowed to estimate the potential curve and the age at peak performance for the population (24.81 ± 0.2) and for each individual as the uncertainty around this curve. With Gaussian mixtures, we identified among all the estimates four types of curves, clustered according to the performance level and the progression per age. Relying on the uncertainty calculated on the progression curve the model created also allow to estimate a score and an uncertainty associated with each cluster for all individuals. The results allows to: i) describe and explain the relationship between age and performance in alpine skiing from a species point of view (at 0.87%) and ii) to provide to sport staffs the estimation of the potential of each individual and her/his typology of progression to better detect sports potential. The entire methodology is based on age and performance data, but the progression identified may depend on parameters specific to alpine skiing.

SEGURANÇA E PREVENÇÃO DE LESÕES ESPORTIVAS EM ESPORTES POPULARES NO GELO E NEVE

ABSTRACT Introduction: Following the development of ice and snow sports tourism projects, the hidden dangers of early extensive construction have gradually emerged. It mainly manifests itself in the sports safety of ice and snow sports tourism projects. Objective: Explore the management strategy of sports safety under the snow and ice sports tourism landscape. Methods: Literature research, interviews, and questionnaires were used to analyze the development in the study area of ice and snow tourism, the tourists themselves, and regional site construction. Finally, the paper analyzes strategies to improve sports safety management in related areas from the landscape manager's point of view. Results: The development of snow and ice sports tourism projects in the study area is satisfactory; however, due to the epidemic's impact, the current situation is relatively low, showing a trend of slow improvement. In terms of sports injury risk, after optimal training and safety management, the proportion of climatic characteristics of the site was 24.81%; the proportion of the population on the ski slopes was 40.92%; the proportion of equipment cleaning and maintenance was 59.23%; the degree of congestion on the ski slopes was 41.30%; the proportion of public safety was 34.42%; the proportion of basic emergency medical treatment was 32.30%; epidemics and other infectious diseases accounted for 83.13% of the total. Follow-up is done before the start, in the process, and after the occurrence of multiple managements. Conclusion: The safety management strategy of snow and ice sports tourism combines the factors of tourists and managers, and has great practical significance, so it is worthy of promotion. Level of evidence II; Therapeutic studies - investigation of treatment outcomes.

Association of personal and equipment-related factors on ACL injury risk in alpine skiers with cautious or risk-taking behaviour: A case-control study.

In recreational alpine skiing ACL injury risk depends on the interaction of individual characteristics and behaviours as well as on equipment-related factors. to evaluate if and to what extent personal characteristics and equipment-related parameters are associated with ACL injury risk in cautious and risk-taking recreational alpine skiers. A retrospective questionnaire-based, case-control study of ACL-injured and uninjured in a cohort of cautious as well as risk-taking recreational skiers was conducted. Participants self-reported their demographics, skiing skill level, and risk-taking behaviour. Ski length, side-cut radius, widths of the tip, waist, and tail were recorded from each participant's skis. Standing heights at the front and rear components of the ski binding were measured with a digital sliding caliper, and a standing height ratio between the front and rear components was calculated. Ski boot sole abrasion at the toe and heel pieces was also measured with the digital sliding caliper. In total, 1068 recreational skiers (50.8% females) with a mean age of 37.8 ± 12.3 years participated, of whom 193 (22.0%) sustained an ACL injury, and 330 (30.9%) participants reported a risk-taking behaviour. Results of the multiple logistic regression analyses revealed that a higher age, a lower skill level, a higher standing height ratio, and greater ski boot sole abrasion at the toe as well as heel pieces were independently associated with an increased ACL injury risk in both the cautious and the risk-taking group. Among cautious skiers, a longer ski length was an additional significant risk factor for sustaining an ACL injury. In conclusion, the same personal and equipment related characteristics contribute to an increase in the ACL injury risk regardless of risk-taking behaviour, with the only difference that longer skis represent an additional risk factor in cautious skiers.

Functional, technological, constructive and compositional solutions of ski complexes

The article analyzes the increased interest in alpine skiing and in the design of sports ski complexes. Classifications of ski resorts, main types and their descriptions are pre-sented. Particular attention is paid to indoor ski resorts, their architectural and landscape solu-tions. The planning classification is studied in detail and presented. The article also discusses many modern engineering technologies, including: air conditioning systems, snow cooling, air dehumidification; use of safe and inexpensive lifts; technologies for making snow on a slope, cooling the snow cover and air, and dehumidifying the air. Studying the topic of ski resorts proves the importance and relevance of the design and construction of indoor multi-functional ski complexes. This presupposes a variety of space-planning solutions that ensure year-round use, and as a result, the development of territories

Study comparing the vibrations recorded by professional and non-professional male athletes in winter sports, skiing vs. snowboarding

Winter sports such as skiing and snowboarding are becoming increasingly popular among all age groups, as practicing these sports has seen an upward trend, which has led to an increase in the number of injuries and pathologies related to them. Practicing skiing/snowboarding entails a series of vibrations occurring in the equipment, their propagation along the kinetic chain impacting both in a positive and negative way the health of the person in question. The study was a comparison, skiing vs. snowboarding, between the vibrations experienced by professional and non-professional athletes, with the main objective of determining which of them produces greater vibrations and identifying the negative and positive effects they have. The study was performed under field conditions using sensors designed to record vibrations on the ski/snowboard (tip/nose and tail), as well as vibration sensors located in the ankle, knee, hip and lumbosacral areas, designed to record the propagation of vibrations along the kinetic chain. The results show a higher level of vibrations recorded on the ski than on the snowboard, while their transmission along the kinetic chain is inversely proportional. The conclusion relates to the choice of skiing/snowboarding. Therefore, due to the Whole-Body Vibration phenomenon, young people are more likely to choose snowboarding due to the possibility of increasing bone quality and quantity, while older people are rather fond of skiing, given its effect along the kinetic chain, which protects the skeletal system. Studies have provided evidence to suggest alpine skiing is an appropriate activity for elderly as a health-enhancing sport. Thus, perhaps alpine skiing could provide the physical activity needed to counteract age-related degradation processes and loss of function.

The EMG, NIRS, and RPE responses to two turn transition techniques in alpine skiing

The EMG, NIRS, and RPE responses to two turn transition techniques in alpine skiing

Some current data and observations regarding the ski slopes in Suceava County, Romania

Some current data and observations regarding the ski slopes in Suceava County, Romania

Sport-specific balance tests account for youth alpine skiers' ranking.

Objective: Alpine skiing requires complex motor skills and fine adjustments to maintain balance in dynamic and challenging conditions. This study aimed to understand whether the balance ability in unspecific (UST) and sport-specific (SST) tasks could depend on the skiers' ranking level. The balance performance of the dominant and non-dominant limbs in the SST was also investigated. Methods: Twenty-five skiers (14.96 ± 1.61yrs; 1.69 ± 0.69m; 59.9 ± 9.52kg) were divided into high-ranking (position < 50) and low-ranking (position > 50) groups. Subjects performed three balance conditions: static (ST), dynamic UST, and dynamic SST. Subjects stood on an unstable board over a force platform during UST. During SST, subjects wore ski boots, grasped ski poles, and each foot was clipped to an unstable board over two force plates. From the center-of-pressure (CoP) trajectory the area of the 95th percentile ellipse and the CoP mean velocity were calculated. Angular displacements were recorded by a 12-camera system, to calculate the full balance (FB), fine (FiB), and gross (GB) balance in UST and SST. Results: Balance control was higher (p < 0.01) in high-ranking than low-ranking skiers only in the SST. Kinematic parameters (i.e., FB, FiB, and GB) showed a higher (p < 0.001) balance performance in SST than UST independently from the group. Dominant and non-dominant limbs motion was similar (Pearson correlation, r = 0.97) in SST independently from the skiers' ranking. Conclusion: High-ranking skiers showed better balance control and performance than low-ranking skiers only when the task was sport-specific. Therefore, we suggest testing balance under sport-specific conditions to discriminate the youth skiers' abilities.