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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
111

Betydelsefulla faktorer för framgångsrika idrottskarriärer inom längdskidåkning och skidskytte

Bergström, Max, Glader, David January 2018 (has links)
Längdskidåkning är en av de mest krävande uthållighetsidrotterna där tävlingstiderna kan variera mellan tre minuter till närmare fyra timmar. Om en idrottsutövare ska nå toppen av sin förmåga krävs det vanligtvis att denne avsätter 20 till 30 timmar per vecka åt träning och tävling under flera års tid. Inom skidskytte behöver utövarna, utöver att vara duktiga längdskidåkare, dessutom bära ett gevär på ryggen och skjuta på måltavlor under högintensiv belastning. Syftet med studien var att kartlägga utövares upplevelser av avgörande och betydelsefulla faktorer för långa framgångsrika idrottskarriärer inom längdskidåkning och skidskytte. I studien användes en kvalitativ metod med semistrukturerade intervjuer, där totalt nio individer deltog. Deltagarna hade tävlat på nationell eller internationell nivå inom längdskidåkning eller skidskytte under minst en tio årsperiod som seniorer. Ett antal övergripande betydelsefulla och avgörande faktorer för framgångsrika idrottskarriärer inom längdskidåkning kunde identifieras. Dessa var: träning och organisation, socioekonomiska faktorer, talang och genetisk potential samt återhämtning. För att nå nationella och internationella framgångar och bedriva en elitsatsning krävs inte bara många års träning, utan även stöd från omgivning i form av familj, tillgång till rätt kompetens och ekonomiskt bidrag eller lön. / Cross country skiing is one of the most demanding endurance sports where the duration of physical effort during a competitive event usually lasts from three minutes up to four hours, or sometimes even longer. To reach national or international elite level, an athlete generally needs to invest 20 to 30 hours of training a week over many years. In biathlon, an athlete not only has to be a good skier, but also be able to carry a rifle and shoot on targets during high intense work load. The aim of this study was to identify athletes' own experiences of the crucial factors that allow for long and successful sport careers in cross country skiing. The study was qualitatively orientated, where semi-structured interviews were used to collect the athlete's perceptions. In total, nine individuals with at least 10 years of competitive cross country skiing or biathlon experience as adults at national or internationallevel participated. The interviews revealed several factors that athletes believe are crucial for achieving long and successful careers. These factors were: 1. Training and organization, 2. Socioeconomic factors, 3. Talent and genetic potential and 4. Recovery. To maintain long and successful careers in cross country skiing, athletes perceive that in addition to factors associated with the training process, support from family, their team and sponsors play important roles.
112

Att tävla eller inte tävla, det är frågan : En studie om varför unga längdskidåkare i Dalarna slutar tävla

Barkegren, Hanna, Sunesson, Minna January 2018 (has links)
Aim This study aimed to investigate at what age young adolescence in Dalarna stops competing in cross-country skiing. Furthermore, to explore possible reasons to why they decide to stop competing. Method To answer the aim a mixed-method was applied. The data collection comprised a quantitative statistical study of when young adolescence from five different teams stopped competing. Additionally, 10 qualitative interviews were conducted with six young adolescence, three coaches and Dalarnas ski associations head of management training. Results The results show that most young adolescents in Dalarnas association stops competing when they reach the age of 12-13. Furthermore, the results suggest that there isn’t just one specific reason to why young adolescence in Dalarnas stops competing. Instead five reoccurring themes: performance, other sports, parents, interpersonal relationships and physical prerequisites were found. Conclusion The results show that the age where most young adolescents stops competing is 12-13 years. Additionally that here is no simple answer to why young adolescent in Dalarna stops competing. Instead the reasons why they decide to stop competing consists of many different factors. With background from the result a conclusion can be made that there is need of improvement, from the association as well as the teams, concerning how to make competition more attractive to youth in Dalarna. The two most common areas to talk about amongst the interview subjects were performance and interpersonal relationships. Therefore those two areas might be a good starting point in the process of keeping youth in competition context. / Syfte Syftet med studien var att undersöka vid vilken ålder barn och ungdomar inom Dalarnas Skidförbund slutar att delta i längdskidtävlingar. Vidare att undersöka möjliga bakomliggande orsaker till att barn och ungdomar slutat tävla. Metod För att besvara syftet med studien applicerades en blandad metod. Delstudie ett är av kvantitativ karaktär och innehåller data gällande vid vilken ålder som unga längdskidåkare inom Dalarnas Skidförbund slutar tävla. Delstudie 2 är av kvalitativ karaktär och består av tio intervjuer. Sex av dessa var med ungdomar som valt att sluta, tre var med aktiva ledare och den sista intervjun var med den utbildningsansvariga i Dalarnas Skidförbund. Resultat Resultatet visar på att barn- och ungdomar inom Dalarnas Skidförbund slutar tävla när de når 12- 13 års ålder. Vidare tyder resultatet på att det inte finns någon specifik enskild anledning till att barn och ungdomar inom Dalarnas Skidförbund slutar att tävla på längdskidor. Istället identifierades fem återkommande teman: Prestation/resultat, andra idrotter, föräldrar, social samhörighet och fysiska förutsättningar. Slutsatser Resultatet visar att de flesta barn och ungdomar inom Dalarnas Skidförbund slutar vid 12-13 års ålder. Vidare att det inte finns något enkelt svar på varför barn och ungdomar i Dalarnas Skidförbund slutar att tävla på längdskidor. Istället grundas deras beslut att sluta tävla på ett flertal olika faktorer. Utifrån studiens resultat går det att dra slutsatsen att det finns förbättringspotential både inom klubbarna men även hos förbundet när det gäller arbetet för att behålla tävlingsaktiva längdskidåkare i distriktet. Det som intervjudeltagarna pratade mest om var prestation/resultat och social samhörighet. Därför kan dessa två områden vara en bra startpunkt att utgå från i arbetet för att behålla tävlingsaktiva inom distriktet.
113

Delkropp- eller helkroppsarbete som återhämtningsstrategi efter upprepade högintensiva arbetsbelastningar på stakergometer hos svenska elitlängdskidåkare. : En kvantitativ studie om återhämtningsstrategier

Tynell, Rikard January 2018 (has links)
Syfte: Studiens syfte var att undersöka skillnaden mellan två olika återhämtningsstrategier, delkroppsarbete (cykelergometer) och helkroppsarbete (rullskidor), avseende effektutveckling vid upprepade högintensiva arbeten på stakergometer. Vidare syftar studien till att undersöka om hjärtfrekvensen och blodlaktatkoncentrationen skiljer sig åt mellan återhämtningsstrategierna. Metod: Sju elitaktiva manliga skidåkare på nationell nivå rekryterades till studien där en crossovermetod tillämpades. En prolog och tre heat med tre minuter högintensivt arbete genomfördes under varje prestationstillfälle. Återhämtningsstrategierna genomfördes med 16 min arbete på en arbetsbelastning vid ≈ 55% av VO2max. De testvariabler som samlades in var laktatkoncentration, effektutveckling samt hjärtfrekvens. Resultat: En signifikant lägre laktatkoncentration påvisades efter helkroppsarbete som återhämtningsstrategi. Dock kunde ingen skillnad mellan strategierna påvisas avseende effektutveckling under heaten. Det kunde heller inte påvisas någon skillnad i hjärtfrekvens före eller under heaten. Slutsatser: Ingen utav de undersökta återhämtningsstrategierna kan rekommenderas framför den andra avseende att optimera sprintprestationsförmågan i längdskidåkning. Däremot visade det sig att helkroppsarbete medförde en lägre blodlaktatkoncentration inför nästkommande heat jämfört mot delkroppsarbete som återhämtningsstrategi. / Purpose: The purpose of the study was to investigate the difference between two recovery strategies, lower-body work (cycle) and whole-body work (roller skiing), regarding to power development in repeated maximum workout on double-poling ergometer. Moreover, the study also aims to investigating whether the heart rate and the blood-lactate concentration differ between the recovery strategies. Method: Seven elite-active male skiers at national level were recruited to the study where a crossover method was applied. A prologue and three heats with three minutes of high-intensity work were performed during each performance. Recovery strategies were carried out with 16 min work at a workload for ≈ 55% of VO2max. The collected test variables in this study were lactate concentration, effect development, and heart rate. Results: A significant difference was found in the lactate concentration after whole-body work as a recovery strategy. However, there was no difference between the strategies in power development during the heats. Furthermore, no difference in heartrates was detected before or during the heats. Conclusions: None of the investigated recovery strategies can be recommended above the other in order to optimize the sprint performance in cross-country skiing. However, whole-body work resulted in a lower blood-lactate concentration prior to next heat compared to lower-body work as recovery strategy.
114

Analýza věku běžců na lyžích na MS a OH v klasickém lyžování v letech 1970 - 2007\\ / Age Analysis of Cross-country Skiing Racers Who Participated in World Championship and Olympic Games in Years 1970-2007.\\

JONÁKOVÁ, Šárka January 2009 (has links)
This thesis is focused on evaluating age structure of cross-country skiing racers who participate in World Championship and Olympic Games. The work shall show if the age of sportsmen can be determined as one of the factors of success, what is the optimal age limit and how is this age limit changed in the course of time or if it stays the same. After studying available literature and after looking up certain data on the internet, the results were evaluated in Excel, the graphs were created and the final report was written. The results showed: the average age often oscillates among 24 and 36 years in the majority of disciplines, it has been rather decreasing mostly in the discipline od women - cross-countra skiing for 5 km both at the World Championship and at the Olympic Games. The age decreases at shorter distance and a little higher age increases or predominates at disciplines for longer distance. The total arithmetic mean of the age of the maximum performance is 27.99 years in cross-country skiing at World Championship and at winter Olympic Games from 1970 to 2007. The arithmetic mean of the age of winners in World Championship is 27.75 years. The arithmetic mean of the age of racers participated in winter Olympic Games is 28.33 years in that time. Average age of women is 27.78 years, average age of men is 28.19 years.
115

SIMULATION OF HORSE-FENCE CONTACT AND INTERACTION AFFECTING ROTATIONAL FALLS IN THE SPORT OF EVENTING

Vega, Gregorio Robles 01 January 2017 (has links)
Rotational falls, or somersault falls, have led to serious and fatal injuries during the cross-country phase of Eventing competitions. Research to improve the safety of the sport began in 2000 after five fatal injuries occurred in the 1999 Eventing season. These efforts led to safety devices such as air jackets, improved helmets, and frangible/deformable fences. The focus of this thesis is to develop a more complete understanding of the horse-fence interaction as the approach motion transitions to a rotational fall. To achieve this, a large distribution of inertial properties was compiled through the development of a cylinder-based inertia approximation and a citizen science effort to gather equine geometrical measurements through a survey distributed by the United States Eventing Association (USEA). Furthermore, fundamental kinematic properties of the horse and rider were gathered from the literature. These distributions were used to conduct a Monte Carlo analysis to examine if the approach conditions of the horse and rider would result in a transition to a rotational fall upon horse-fence contact. Through the analysis the sensitivity of the main control parameters was explored to determine the dominant variables in the transition.
116

App based ski management with performance predictions

Nelson, Lars January 2018 (has links)
This report aims to solve a problem for the   waxers in the Swedish National Cross-country Ski Team, which hereafter will   be referred to as the national team. The problem in hand is that currently,   the national team lacks a system for book-keeping of ski pairs and ski tests.   Also, the project intends to provide a tool for predicting the best ski pairs   in given conditions. The report describes cross-country skis and factors that   affect the performance of these skis. Moreover, this report presents the   testing procedure of the national team. The project provides a solution to   the problem in hand by developing a web service based on Django and Django   REST Framework and an iOS application to handle the user interaction. The app   was tested and approved by the waxers of the national team. To predict the   best performing skis in given conditions, the three Machine Learning   algorithms Support Vector Machine (SVM), Decision Tree, and Artificial Neural   Network (ANN) is implemented and evaluated. Experimental results indicate   that the ANN algorithm has better accuracy than the Decision Tree, and that   the SVM algorithms and that the SVM was performing slightly worse than the   other two, when applied on test data which is artificially generated based on   the experience of the national team. All three Machine Learning algorithms   perform better in terms of mean accuracy which is significantly higher   compared to the accuracy of a baseline algorithm. The report suggests that   the accuracy of the ANN algorithm is high enough to be useful for the   national team.
117

Ett nytt isokinetiskt bålstyrketest för elitskidåkare / A new isokinetic core strength test for elite cross country skiers

Stenberg, Simon January 2021 (has links)
Bakgrund: I dagens längdskidåkning har stakningen utvecklats till att bli en avgörande komponent till att prestera framgångsrikt, framförallt inom sprintåkningen där de höga hastigheterna ställer stora krav på överkroppsstyrka. Bålens styrka bör därför testas för att planera och utvärdera träning vilket endast sker genom statiska och uthållighetbaserade övningar som inte är speciellt idrottsspecifika. Ett isokinetiskt bålstyrkettest för elitskidåkare saknas i dagsläget men med Biodex System 3 är det möjligt att utveckla. Syftet med studien var att ta fram ett testprotokoll för isokinetisk bålstyrka i Biodex och analysera sambandet mellan isokinetisk, isometrisk och explosiv bålstyrka samt ställa resultatet mot FIS-punkter i sprint. Metod: Elva elitskidåkare deltog i studien där de efter ett testbatteri med explosiva och statiska styrketester genomförde ett isokinetiskt bålstyrketest i Biodex. I testet skulle forskningspersonerna fastspända i sittande position producera maximal koncentrisk kraft i 50-90° höftflexion under sex repetitioner under en standardiserad hastighet på 60° per sekund. Datat analyserades med Spearmans korrelationskoefficient (r) och signifikansvärdet var: p <0,05.  Resultat: Ett starkt positivt samband (r=0,79, p <0,05) fanns mellan det isokinetiska bålstyrketestet (Biodexₘₐₓ) och det isometriska bålstyrketestet (Isobålₘₐₓ). För de manliga åkarna påvisades ett starkt positivt samband mellan Biodexₘₐₓ och FIS-punkter i sprint (r=0.89, p<0.05) samt Biodexₘₐₓ och vikt (r=0,92 p <0,05). Inga fler statistiskt signifikanta samband kunde påvisas. Konklusion: Studien visar att det finns ett tydligt samband mellan Biodexₘₐₓ och Isobålₘₐₓ samt Biodexₘₐₓ och vikt bland män. Ingen signifikant koppling mellan Biodexₘₐₓ och bollkastet samt Biodexₘₐₓ och längd bland män kunde hittas. Sambandet mellan Biodexₘₐₓ och FIS-punkter i sprint bland män visar att högt resultat i biodextestet tyder på sämre prestationsförmåga i sprint. Inga stora slutsatser kan dras från resultatet på grund av för lågt deltagarantal. Däremot kan isokinetisk bålstyrka nu testas i Biodex och bidra till framtida forskning. / Backgrund: Double poling has developed into a crucial component for cross country skiing performance, especially in sprint where high velocities place great demands on upper body strength. Core strength should therefore be tested to evaluate training which only occurs through static and endurance-based exercises that are not particularly sports-specific. An isokinetic core strength test for elite skiers is currently not available but the Biodex System 3 makes it possible to develop. The purpose of the present study was to develop a protocol for isokinetic core strength and analyze the relationship between isokinetic, isometric and explosive core strength and also compare the result to FIS-points in sprint.  Method: Eleven cross country skiers participated in the study where they after a set of explosive and static tests completed an isokinetic core strength test in the Biodex. The subjects were strapped to the Biodex into a sitting position where they produced maximum concentric force in 50-90° hip flexion during six repetitions at a standardized speed of 60° per second. The data was analysed with Spearman korrelationskoeffizient (r) och the level of significance was: p <0,05. Result: A strong positive relationship (r=0,79, p <0,05) was found between the isokinetic core strength test (Biodexₘₐₓ) and the isometric core strength test (Isobålₘₐₓ). For male skiers a strong positive relationship was found between Biodexₘₐₓ and FIS-point in sprint (r=0.89, p<0.05) and Biodexₘₐₓ and weight (r=0,92 p <0,05). No more statistically significant results were observed. Conclusion: This study shows a strong relationship between Biodexₘₐₓ against Isobålₘₐₓ and Biodexₘₐₓ and weight among men. No statistically significant connection was found between Biodexₘₐₓ and the ball throw and Biodexₘₐₓ and length among men. The relationship between Biodexₘₐₓ and FIS-points in sprint among men indicates that high values in the Biodex means a decreased performance in sprint. No major conclusions can be made from the results due to the low numbers of participants. However, isokinetic core strength can now be tested in the Biodex and contribute to future recherch.
118

Komparativní analýza vybraných bruslařských způsobů v běhu na lyžích / Comparative analysis of chosen skating techniques at cross-country skiing

Kmoch, Jan January 2011 (has links)
Author's first name and surname: Jan KMOCH Department: FTVS UK, Department of Outdoor Sports Supervisor: Mgr. Radka Bačáková Abstract Title: Comparative analysis of chosen skating techniques at cross-country skiing. Objective: Comparison of leg muscle coordination at different skating techniques in one locomotive cycle at cross-country skiing and free bipedal walk. Methods: Comparative analysis of electromyography records of muscle activation in combination with kinematography analysis of video record. Results: There were found similarities and differences in muscle activation timing at observed muscles. Keywords: skating at cross-country skiing, bipedal walk, surface electromyography
119

Komplexní zhodnocení lyžařských výcvikových kurzů na vybraných základních školách v ČR / Komplexní hodnocení lyžařských výcvikových kurzů na základních školách v ČR.

Hraško, Petr January 2014 (has links)
1 Abstract Name: Complex evaluation of the basic school ski courses in the Czech republic Objective: The objective of this diploma thesis is to evaluate complexly a chosen basic school ski school courses in the Czech republic according to five above mentioned criteria and to confirm or dismiss hypothesisses. Methodology: I created a non-standardized questionnare with open-ended, semi close-ended and close- ended questions to evaluate ski courses according to the above mentioned criteria. This questionnare was sended non-anonymously online via survio.com to randomly chosen basic schools in every single province of the Czech republic. Collected data were statistically analysed in the Survio and Microsoft EXCEL® programm and the results were eriched with graphs and commentary. Results: In this diploma thesis basic school ski courses were evaluated according to determined criteria, at least one hypothesis was related to every criterion. I could confirm that the majority of ski course leaders are ski instructors (50 hours training, no trade licence). I could confirm four other hypothesisses as well, i. e. cross-country skiing is an essential part of more than 50% ski courses, less than 50% of pupils attend basic school ski courses, the majority of ski course instructors are teaching in accordance with the...
120

Experimental test setups and simulations in skiing mechanics

Swarén, Mikael January 2014 (has links)
Product testing and development are essential parts in sports and for the athletes in their quest to reach the podium. Manufacturers of sports equipment often use basic test methods which do not test the equipment in a sports specific way. Much of the equipment used by world-class athletes is chosen based only on subjective tests and the athletes’ feelings. One short term aim was therefore to develop test methods for objective tests of sports equipment that also tested the equipment in a sports  specific  way.  Another  aim  was  to  integrate  mechanics  and  simulations  to  enhance  the understanding of the test results. The more long term aims are to contribute to increased theoretical knowledge regarding test methods for sports equipment and to contribute to the development of test  methods  to  create  new  and  better  sports  equipment.  Experimental  tests  combined  with simulations  can  give  valuable  information  to  improve  the  performance  and  safety  of  sports equipment. Three studies dealt with the issue of objective yet sport specific test methods for sports equipment. The main methodological advancement is the modification of established test methods together  with  conventional  mechanics  calculations.  New  test  devices  and  methodologies  are proposed for alpine ski helmets and cross-country ski poles. Suggestions are given for improved test setups as well as theoretical simulation are introduced for glide tests of skis. The results show how sport   specific   test   methodologies   together   with   theoretical   calculations   can   improve   the objectiveness and relevance when testing sports equipment. However, the collected and used data require high precision to obtain high accuracy in the simulations. High data accuracy can be an issue in field measurements but also due to manufacturers not disclosing key material data. Still, the used methods  and  calculations  in  this  thesis  produce  relevant  and  reliable  results  which  can  be implemented to accurate evaluations of different sports equipment. Even though it has not been a first priority aim in this work, the results from the alpine helmet study have been used by helmet manufacturers to design new helmets with increased safety properties. This further show how an objective and sport specific test approach together with theoretical simulation can improve sports equipment and in the longer perspective, also the athletes’ performances. / <p>QC 20140423</p>

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