| 1. |
- Rosso, V., et al.
(författare)
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Balance Perturbations as a Measurement Tool for Trunk Impairment in Cross-Country Sit Skiing
- 2019
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Ingår i: Adapted Physical Activity Quarterly. - : Human Kinetics. - 0736-5829 .- 1543-2777. ; 36:1, s. 61-76
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Tidskriftsartikel (refereegranskat)abstract
- In cross-country sit-skiing, the trunk plays a crucial role in propulsion generation and balance maintenance. Trunk stability is evaluated by automatic responses to unpredictable perturbations; however, electromyography is challenging. The aim of this study was to identify a measure to group sit-skiers according to their ability to control the trunk. Seated in their competitive sit-ski, 10 male and 5 female Paralympic sit-skiers received 6 forward and 6 backward unpredictable perturbations in random order. k-means clustered trunk position at rest, delay to invert the trunk motion, and trunk range of motion significantly into 2 groups. In conclusion, unpredictable perturbations might quantify trunk impairment and may become an important tool in the development of an evidence-based classification system for cross-country sit-skiers.
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| 2. |
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| 3. |
- Rosso, V., et al.
(författare)
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Evaluating objective measures of impairment to trunk strength and control for cross-country sit skiing
- 2021
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Ingår i: Sports Engineering. - : Springer Science and Business Media LLC. - 1369-7072 .- 1460-2687. ; 24:6
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Tidskriftsartikel (refereegranskat)abstract
- In 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 perfor-mance. 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 balance perturbations to measure trunk control. Tests were repeated on two separate days and test–retest reliability of trunk strength and trunk control measures was evaluated. A cluster analysis was run and correlation was evaluated, including all strength and control measures, to identify the measures that contributed most to clustering participants. Intraclass correlations coefficients (ICC) were 0.71 < ICC < 0.98 and 0.83 < ICC < 0.99 for upright seated press and perturbations, respectively. Cluster analysis identified three clusters with relevance for strength and balance control measures. For strength, in upright seated press peak anterior pushing force without backrest (effect size = 0.77) and ratio of peak anterior pushing force without and with backrest (effect size = 0.72) were significant. For balance control measures, trunk range of motion in forward (effect size = 0.81) and backward (effect size = 0.75) perturbations also contributed. High correlations (− 0.76 < r < − 0.53) were found between strength and control measures. The new testing device, protocol, and the cluster analysis show promising results in assessing impairment of trunk strength and control to empower an evidence-based classification.
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| 4. |
- Rosso, V, et al.
(författare)
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Measures of impairment in cross-country sit skiing
- 2019
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Ingår i: 8th International Congress on Science and Skiing (ICSS) - Abstract book. Vuokatti, Finland, March 11th - 15th, 2019. - 9789513976835
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Konferensbidrag (refereegranskat)
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| 5. |
- Rosso, V., et al.
(författare)
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Simulated skiing as a measurement tool for performance in cross-country sit-skiing
- 2019
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Ingår i: Proceedings of the Institution of Mechanical Engineers Part P-Journal of Sports Engineering and Technology. - : SAGE Publications. - 1754-3371 .- 1754-338X. ; 233:4, s. 455-466
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Tidskriftsartikel (refereegranskat)abstract
- The International Paralympic Committee mandates the development of an evidence-based classification system, which requires a measure of performance. Performance in cross-country sit-skiing is mainly dependent on force generated during the poling phase and is enhanced by trunk flexion-extension movements. Since all sit-skiers have neuromuscular impairment, but different ability to control the trunk, this study aimed to verify if simulated action of poling on an adapted ergometer, together with a cluster analysis, could be used for grouping participants with different impairments according to their performance. On the ergometer, eight male and five female participants performed seven poling cycles at maximal speed, while sitting on personal sit-ski. Based on maximal speed, generated force, cycle characteristics, and trunk kinematics, cluster analysis divided participants into three groups showing good accuracy, sensitivity, and precision. Although a validation of this exploratory study is necessary, skiing on the ergometer could be considered as sport-specific measure of performance and may become an interesting tool in the development of an evidence-based classification system for cross-country sit-skiing.
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| 6. |
- Ainegren, M, et al.
(författare)
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Effects of drafting on VO2 in double poling XC-skiing
- 2019
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Ingår i: 8th International Congress on Science and Skiing (ICSS) - Abstract book. Vuokatti, Finland, March 11th - 15th, 2019, s. 41. - 9789513976835
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Konferensbidrag (refereegranskat)
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| 7. |
- Karczewska-Lindinger, Magdalena, 1986, et al.
(författare)
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Race and split time analysis in para nordic sit-skiing
- 2019
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Ingår i: 8th International Congress on Science and Skiing (ICSS) - Abstract book. Vuokatti, Finland, March 11th - 15th, 2019, s. 69. - 9789513976835
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Konferensbidrag (refereegranskat)
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| 8. |
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| 9. |
- Lemmettylä, T., et al.
(författare)
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The Development and Precision of a Custom-Made Skitester
- 2021
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Ingår i: Frontiers in Mechanical Engineering. - : Frontiers Media SA. - 2297-3079. ; 7
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Tidskriftsartikel (refereegranskat)abstract
- In the sport of cross-country skiing, equipment has a direct influence on results. Ski teams do extensive testing of different ski base grinds and products on a yearly basis. To achieve reliable results, the quality of methods used for testing skis needs to be taken in to account in addition to factors including the physical characteristics of testing personnel and changes in weather conditions. The aim of this study was to introduce a custom-made skitester, that was developed for testing skis on real snow, in laboratory conditions, and to evaluate its precision. The current skitester is capable of glide testing both classic and skate skis as well as kick simulation for the testing of grip waxes. In the present study, glide testing precision was completed in three different conditions. Velocity and pressure of skis were evaluated in three different temperature conditions. During kick simulation, precision was determined in one temperature condition. For glide testing, the precision of the measurement unit was able to distinguish the differences between skis with a relative variation of 0.6–1.1%. However, the track preparation process caused variation. For kick simulation, precision of the measurement unit was slightly higher (2.5%), and track preparation caused less variation. The skitester is capable of distinguishing the differences between both skate and classic cross-country skis with certain limitations.
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| 10. |
- Lindinger, Stefan, 1968, et al.
(författare)
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Air drag and aerodynamics in skiing
- 2019
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Ingår i: 8th International Congress on Science and Skiing (ICSS) - Abstract book. Vuokatti, Finland, March 11th - 15th, 2019, s. 88. - 9789513976835
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Konferensbidrag (refereegranskat)
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