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2016
The purpose of this study was to measure the difference in normal force under both feet during alpine skiing giant slalom turns. Eleven experienced alpine skiers performed a giant slalom course at race intensity. All trials were recorded synchronously using a video camera and a plantar pressure measuring system. The mean force on the grouped two feet varied from 0.7 BW at the start of a turn to 1.5 BW during the steering phase of a turn performed in a steep slope condition. When skiing on FLAT slope condition, it reached only 1.3 BW. Results also showed that the outside foot receives significantly more pressure than the inside foot during the entire turn except the initiation phase. This last finding is not affected by slope steepness.
Sensors
Small differences in turn cycle structure, invisible to the naked eye, could be decisive in improving descent performance. The aim of this study was to assess the influence of turn cycle structure on the performance of elite alpine skiers using an inertial measurement unit (IMU) in different slalom (SL) course settings. Four SL courses were set: a flat-turned (FT), a steep-turned (ST), a flat-straighter (FS) and a steep-straighter (SS). Five elite alpine skiers (21.2 ± 3.3 years, 180.2 ± 5.6 cm, 72.8 ± 6.6 kg) completed several runs at maximum speed for each SL course. A total of 77 runs were obtained. Fast total times correlate with a longer initiation (INI) time in FT, a shorter steering time out of the turn (STEOUT) in the FT and FS and a shorter total steering time (STEIN+OUT) in the FT and SS courses. The linear mixed model used for the analysis revealed that in the FT-course for each second increase in the INI time, the total time is reduced by 0.45 s, and for every one-second...
Applied Sciences
Background: Although many of the movements of skiers are asymmetric, little is presently known about how such asymmetry influences performance. Here, our aim was to examine whether asymmetries in technique and the ground reaction forces associated with left and right turns influence the asymmetries in the performance of elite slalom skiers. Methods: As nine elite skiers completed a 20-gate slalom course, their three-dimensional full-body kinematics and ground reaction forces (GRF) were monitored with a global navigation satellite and inertial motion capture systems, in combination with pressure insoles. For multivariable regression models, 26 predictor skiing techniques and GRF variables and 8 predicted skiing performance variables were assessed, all of them determining asymmetries in terms of symmetry and Jaccard indices. Results: Asymmetries in instantaneous and sectional performance were found to have the largest predictor coefficients associated with asymmetries in shank angle a...
Frontiers in Physiology, 2021
The ground reaction forces (GRF) associated with competitive alpine skiing, which are relatively large, might be asymmetric during left and right turns due to asymmetries in the strength of the legs and torso and the present investigation was designed to evaluate this possibility. While skiing a symmetrical, 20-gate slalom course, the asymmetries of 9 elite alpine skiers were calculated on the basis of measurements provided by inertial motion units (IMU), a Global Navigation Satellite System and pressure insoles. In addition, specialized dynamometers were utilized to assess potential asymmetry in the strength of their legs and torso in the laboratory. In total, seven variables related to GRF were assessed on-snow and eight related to strength of the legs and torso in the laboratory. The asymmetries in these parameters between left and right turns on snow were expressed in terms of the symmetry (SI) and Jaccard indices (JI), while the asymmetries between the left and right sides of t...
Frontiers in Physiology, 2019
Alpine skiing has been an Olympic event since the first Winter Games in 1936. Nowadays, skiers compete in four main events: slalom, giant slalom, super-G and downhill. Here, we present an update on the biomechanics of alpine ski racers and their equipment. The technical and tactical ability of today’s world-class skiers have adapted substantially to changes in equipment, snow conditions and courses. The wide variety of terrain, slopes, gate setups and snow conditions involved in alpine skiing requires skiers to continuously adapt, alternating between the carving and skidding turning techniques. The technical complexity places a premium on minimizing energy dissipation, employing strategies and ski equipment that minimize ski-snow friction and aerodynamic drag. Access to multiple split times along the racing course, in combination with analysis of the trajectory and speed provide information that can be utilized to enhance performance. Peak ground reaction forces, which can be as hig...
Journal of Sports Sciences, 2003
International journal of exercise science, 2020
The purpose of this study was to investigate the magnitude of force a slopestyle skier is exposed to when landing either forward or switch in a big air jump. Ten male freeskiers (age 23 ± 6 years; height 179.2 ± 5.4 cm; body mass 72.5 ± 8.6 kg; mass of equipment 16.7 ± 1.4 kg; total mass 89.2 ± 8.6 kg) participated and each performed five 180 jumps and five switch 180 jumps in a randomized order. Forces were quantified using pressure insoles. The results showed a force of 1446 ± 367 N (2.04 ± 0.46 times body mass) for the 180 jump and a force of 1409 ± 257 N (1.99 ± 0.28 times body mass) for the switch 180 jump. There was no difference in force between the 180 jump and the switch 180 jump, p=0.582. There was a trend for the switch 180 for a correlation between a heavier body mass and a greater force (r = 0.604, r2 = 0.365, p = 0.064) as well as a heavier total mass and a greater force (r = 0.621, r2 = 0.385, p = 0.055). This study shows that the force when landing a big air jump is ...
Journal of applied biomechanics, 2010
Computational and Mathematical Methods in Medicine, 2014
Footwear Science, 2009
Journal of Sports Science and Medicine, 2015
Human Movement, 2008
Human Movement, 2008
Procedia Engineering, 2014
Sports Engineering, 2013
Frontiers in Physiology
Journal of neuroengineering and rehabilitation, 2015
British Journal of Sports Medicine, 2012
Journal of Science in Sport and Exercise
Sports Medicine International Open, 2021
Research quarterly for exercise and sport, 2011
Journal of sports science & medicine, 2015
Scientific journal of Kurdistan University of Medical Sciences, 2016
Journal of applied biomechanics, 2008
Scandinavian Journal of Medicine & Science in Sports, 2013
Medicine & Science in Sports & Exercise, 2000
Frontiers in Physiology
Sport-Orthopädie - Sport-Traumatologie - Sports Orthopaedics and Traumatology, 2013
Journal of Anatomy, 2014
Sports Technology, 2009
Facta universitatis. Series physical education and sport, 2016
Applied Sciences
Sport Mont Journal, 2013
IEEE Transactions on Instrumentation and Measurement, 2000
The Open Sports Sciences Journal
Medicine & Science in Sports & Exercise, 1999