Search results for "skiing"
showing 10 items of 73 documents
The effect of wind on jumping distance in ski jumping depends on jumpers’ aerodynamic characteristics
2022
Several studies have suggested re-evaluation of the wind compensation system (WCS) of the International Ski Federation (FIS). It was introduced in 2009, and since then, the system has been modified considerably, but major shortcomings have still remained. The present study compared the effect of tail/head wind on two reference jumps with different aerodynamic properties (Cd and Cl) during the flight phase. Jump distance and total tangential wind speed data of world cup competitions of the season 2020/2021 were used to analyse the FIS WCS and to offer basic information of wind effects. The correlation between the total tangential wind speed and the jump distance varied strongly among the ana…
Vuosikymmenet suomalaisen hiihtohistorian kulisseissa : tapaustutkimus vapaaehtoistoiminnan merkityksistä ja muutoksista Lahden MM-hiihdoissa
2017
Lahden Salpausselällä on pitkät perinteet pohjoismaisten hiihtolajien kilpailuareenana. Pohjoismaisten hiihtolajien MM-kilpailut on järjestetty siellä yhteensä seitsemän kertaa seitsemällä eri vuosikymmenellä. Lisäksi Lahdessa on kilpailtu vuosittain pohjoismaisten hiihtolajien maailmancupin osakilpailut, Salpausselän kisat. Kumpaakaan näistä tapahtumista ei oltaisi voitu järjestää vuosien saatossa ilman sitoutuneiden ja kokeneiden vapaaehtoisten joukkoa. Lukuisat vapaaehtoiset ovat olleet mukana kisojen vapaaehtoistoiminnassa jo useamman vuosikymmenen ajan. Tässä laadullisessa tapaustutkimuksessa selvitettiin, millaisia merkityksiä pitkään vapaaehtoisena toimineet antavat vapaaehtoistoimin…
Evaluating objective measures of impairment to trunk strength and control for cross-country sit skiing
2021
AbstractIn Paralympic cross-country sit skiing, athlete classification is performed by an expert panel, so it may be affected by subjectivity. An evidence-based classification is required, in which objective measures of impairment must be identified. The purposes of this study were: (i) to evaluate the reliability of 5 trunk strength measures and 18 trunk control measures developed for the purposes of classification; (ii) to rank the objective measures, according to the largest effects on performance. Using a new testing device, 14 elite sit-skiers performed two upright seated press tests and one simulated poling test to evaluate trunk strength. They were also subjected to unpredictable bal…
Take-off analysis of the Olympic ski jumping competition (HS-106m).
2007
Abstract The take-off phase (approximately 6 m) of the jumps of all athletes participating in the individual HS-106 m hill ski jumping competition at the Torino Olympics was filmed with two high-speed cameras. The high altitude of the Pragelato ski jumping venue (1600 m) and slight tail wind in the final jumping round were expected to affect the results of this competition. The most significant correlation with the length of the jump was found in the in-run velocity ( r =0.628, p n =50). This was a surprise in Olympic level ski jumping, and suggests that good jumpers simply had smaller friction between their skis and the in-run tracks and/or the aerodynamic quality of their in-run position …
Is it still important to be light in ski jumping?
2019
In ski jumping low body weight development resulted in some serious underweight problems and therefore the International Ski Federation (FIS) decided to solve the problem by relating maximum ski length to Body Mass Index (BMI) in 2004. The present study examined the current relationship between body weight, ski length and performance (jumping distance) in ski jumping. By adopting the BMI regulation to specifications for competition equipment, the FIS succeeded in stopping the alarming development of underweight problems in ski jumping. However, as the results of the present study show, the BMI regulation adopted by the FIS has reduced the advantage of being light, but despite the use of sho…
Arm swing during skating at different skiing speeds affects skiing mechanics and performance
2018
Arm swing has been shown to lead to greater maximal speed and movement economy in cross -country skiing. The current study aimed to investigate how arm swing alters skiing mechanics and contributes to performance and acceleration of the athlete’s centre of mass (COM). While skiing on snow seven highly skilled cross -country skiers simulated V2 -alternate skating without using ski poles and with double or single arm swing and without arm swing . During leg push -off the linear momentum of the body increased due to arm swing. Simultaneously, linear momentum of the arm(s) decreased in arm swing trials, indicating a transfer of momentum from arms to the rest of the body and being more prevalent…
Speed control of the V2 skating technique in elite cross-country skiers
2016
The aim was to examine how skiers control skiing speed using V2-skating. Subjects skied with three submaximal and maximal speeds on 100 m 4° uphill. Cycle variables and force parameters form the arms and legs were analysed. Cycle rate increased up to the maximum speed. Cycle length increased from the slowest speed to the all other speeds. Pole force and delta leg force increased up to the maximum speed. Ranges of motions and angular velocities of kick flexion and extension with knee and hip joints increased till highest submaximal speed. Speed was regulated with cycle length and rate while the latter was dominant after ∼5.0 m/s. Higher speed was reached with higher forces from arms and leg…
Contribution and effectiveness of ski and pole forces in selected roller skiing techniques on treadmill at moderate inclines
2023
BackgroundMost of the studies about the effects of incline on cross-country skiing are related to the metabolic efficiency. The effective skiing biomechanics has also been indicated to be among the key factors that may promote good performance. The aims of this study were to provide biomechanical characteristics and investigate the relative contribution and effectiveness of ski and pole forces in overcoming the total external resistance with double poling (DP) and Gear 3 (G3) techniques at varying moderate uphill inclines.Methods10 male cross-country skiers participated in this study. Custom-made force measurement bindings, pole force sensors, and an 8-camera Vicon system were used to colle…
Propulsion Calculated by Force and Displacement of Center of Mass in Treadmill Cross-Country Skiing
2022
This study evaluated two approaches for estimating the total propulsive force on a skier’s center of mass (COM) with double-poling (DP) and V2-skating (V2) skiing techniques. We also assessed the accuracy and the stability of each approach by changing the speed and the incline of the treadmill. A total of 10 cross-country skiers participated in this study. Force measurement bindings, pole force sensors, and an eight-camera Vicon system were used for data collection. The coefficient of multiple correlation (CMC) was calculated to evaluate the similarity between the force curves. Mean absolute force differences between the estimated values and the reference value were computed to evalua…
Effects of Individual Changes in Training Distribution on Maximal Aerobic Capacity in Well-Trained Cross-Country Skiers: A Follow-Up Study
2021
The purpose of this study was to evaluate individual changes in training distribution and the subsequent effects on maximal oxygen uptake (VO2max). The participants were well-trained cross-country skiers who had performed a year with no substantial changes in training prior to this study. Six cross-country skiers, who were participants in a larger previous study, volunteered for a follow-up study. All skiers performed self-motivated changes in training distribution for a new preparation period in this follow-up, generally by more high-intensity training (HIT). All training characteristics were registered from training diaries. During the follow-up period, all skiers performed an incremental…