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- Lindinger, Stefan J, et al.
(författare)
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Biomechanical pole and leg characteristics during uphill diagonal rollerskiing
- 2009
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Ingår i: Sports Biomechanics. - : Informa UK Limited. - 1476-3141 .- 1752-6116. ; 8:4, s. 318-333
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Tidskriftsartikel (refereegranskat)abstract
- Diagonal skiing as a major classical technique has hardly been investigated over the last two decades, although technique and racing velocities have developed substantially. The aims of the present study were to 1) analyse pole and leg kinetics and kinematics during submaximal uphill diagonal roller skiing and 2) identify biomechanical factors related to performance. Twelve elite skiers performed a time to exhaustion (performance) test on a treadmill. Joint kinematics and pole/plantar forces were recorded separately during diagonal roller skiing (98; 11 km/h). Performance was correlated to cycle length (r ¼ 0.77; P , 0.05), relative leg swing (r ¼ 0.71), and gliding time (r ¼ 0.74), hip flexion range of motion (ROM) during swing (r ¼ 0.73) and knee extension ROM during gliding (r ¼ 0.71). Push-off demonstrated performance correlations for impulse of leg force (r ¼ 0.84), relative duration (r ¼ 20.76) and knee flexion (r ¼ 0.73) and extension ROM (r ¼ 0.74). Relative time to peak pole force was associated with performance (r ¼ 0.73). In summary, diagonal roller skiing performance was linked to 1) longer cycle length, 2) greater impulse of force during a shorter push-off with larger flexion/extension ROMs in leg joints, 3) longer leg swing, and 4) later peak pole force, demonstrating the major key characteristics to be emphasised in training.
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| 3. |
- Stoeggl, Thomas Leonhard, et al.
(författare)
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Double-Poling Biomechanics of Elite Cross-country Skiers : Flat versus Uphill Terrain
- 2016
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Ingår i: Medicine & Science in Sports & Exercise. - 0195-9131 .- 1530-0315. ; 48:8, s. 1580-1589
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Tidskriftsartikel (refereegranskat)abstract
- Introduction: In light of the recent revolutionary change in the use of the doublepoling (DP) technique in cross-country skiing, our purpose was to compare the associated kinetics and kinematics on flat (DPflat) and uphill terrain (DPup), as well as to identify factors that determine performance. Methods: Thirteen elite male cross-country skiers completed two incremental speed tests (V-peak) involving roller skiing with the DP technique at moderate (13 and 24 km.h(-1)) and high speed (15 and 28.5 km.h(-1)) on a treadmill that was flat (1 degrees) or tilted uphill (7 degrees). Pole forces and three-dimensional whole-body kinematics were monitored simultaneously. Results: In comparison to DPflat, during DPup, swing times were much shorter (-48%) and peak pole forces greater (+13%) and generated later during the poling phase (+68%), with higher impulses for all force components (+87%-123%). Furthermore, pole forces were 18% more effectively oriented for propulsion. During DPup, the skiers demonstrated more flexed elbows, as well as shoulder angles that were less flexed in the forward direction and less abducted throughout the poling phase, together with more highly flexed knee and ankle joints, a more upright thorax, less flexed hips, and a shortened backward swing after pole off. With DPup, the skiers raised their center of mass 25% more, attaining maximal heel raise and maximal vertical position at a timepoint closer to pole plant compared with flat. On the uphill incline, the magnitude of V-peak was positively related to body mass, relative pole length (% body height), and magnitude of heel raise. Conclusions: The present findings provide novel insights into the coordination, kinetics and kinematics of elite skiers while DP on flat and uphill terrain.
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| 4. |
- Stoeggl, Thomas L., et al.
(författare)
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Pacing, Exercise Intensity, and Technique by Performance Level in Long-Distance Cross-Country Skiing
- 2020
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Ingår i: Frontiers in Physiology. - : Frontiers Media SA. - 1664-042X. ; 11
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Tidskriftsartikel (refereegranskat)abstract
- Introduction Long-distance cross-country skiing (XCS) has gained increased popularity within the past decades. However, research about long-distance XCS is limited; therefore, the aim of this study was to analyze the intensity distribution, technique application, and pacing strategies during long-distance XCS racing. Methods Heart rate (HR) and section skiing speeds of 9 elite (ranked 1-100) and 10 amateur skiers (ranked 101-1,500) during the 90-km Vasaloppet race were collected. In addition, during the first uphill, the first 1,000 skiers were video-recorded to analyze the applied skiing strategy (e.g. grip-waxed skis versus exclusive double poling). Results Mean race intensity was 82% of maximal HR and was not different between performance groups even though elite skiers skied similar to 15% faster than amateurs. There was an interaction effect of section x group with a pronounced decrease in HR in amateurs compared with more even pacing in elite skiers (0.13 vs. 0.04% decrease/km) and skiing at higher percentage in the high-intensity zones in elite compared with amateurs (46 vs. 24%). Ninety-eight percent of the top 100 skiers and 59% of the first 1,000 skiers used exclusively double poling. Conclusion Elite and amateur skiers ski at comparable mean race exercise intensity, but they have clear differences in skiing speed. The difference in the pacing profiles between elite and amateur skiers (more even vs. distinct positive pacing) demonstrate the greater capacity of the former with respect to physiological capacity and highlights that amateurs seem to start too fast according to their capacities. The exclusive application of the double poling technique is no longer a phenomenon of elite skiers but is widely used among the top 1,000 ranked skiers.
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| 5. |
- Stoeggl, Thomas, et al.
(författare)
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Pacing and predictors of performance during cross-country skiing races : A systematic review
- 2018
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Ingår i: Journal of Sport and Health Science. - : Elsevier BV. - 2095-2546 .- 2213-2961. ; 7:4, s. 381-393
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Forskningsöversikt (refereegranskat)abstract
- Background: Cross-country skiing (XCS) racing, a popular international winter sport, is complex and challenging from physical, technical, and tactical perspectives. Despite the vast amount of research focusing on this sport, no review has yet addressed the pacing strategies of elite XCS racers or the factors that influence their performance. The aim was to review the scientific literature in an attempt to determine the effects of pacing strategy on the performance of elite XCS racers. Methods: Four electronic databases were searched using relevant subject headings and keywords. Only original research articles published in peer-reviewed journals and the English language and addressing performance, biomechanics, physiology, and anthropometry of XCS racers were reviewed. Results: All 27 included articles applied correlative designs to study the effectiveness of different pacing strategies. None of the articles involved the use of an experimental design. Furthermore, potential changes in external conditions (e.g.,weather, ski properties) were not taken into consideration. A comparable number of studies focused on the skating or classical technique. In most cases, positive pacing was observed, with certain indications that higher-level athletes and those with more endurance and strength utilized a more even pacing strategy. The ability to achieve and maintain a long cycle length on all types of terrain was an important determinant of performance in all of the included studies, which was not the case for cycle rate. In general, uphill performance was closely related to overall race performance, with uphill performance being most closely correlated to the success of female skiers and performance on flat terrain being more important for male skiers. Moreover, pacing was coupled to the selection and distribution of technique during a race, with faster skiers employing more double poling and kick double poling, less diagonal stride, and more V2 (double dance) than V1 (single dance) skating across a race. Conclusion: We propose that skiers at all levels can improve their performance with more specific training in techniques (i.e., maintaining long cycles without compromising cycle rate and selecting appropriate techniques) in combination with training for endurance and more strength. Furthermore, we would advise less experienced skiers and/or those with lower levels of performance to apply a more even pacing strategy rather than a positive one (i.e., starting the race too fast).
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