The purpose with this study was to investigate the effect of a carbohydrate (CHO) mouth rinse protocol on simulated cross country (XC) sprint. The primaryaim was to investigate ifa 10 secCHO solutionmouth rinsingprotocolimprovedthe finish timein a simulated cross country (XC) sprint(800 meters for female and 1000 meters for male) compared with control (CON).The second aim was to examif post-finish blood lactateconcentrationwouldbe lowercompared with CONwith mouth rinsing. Seven participants(four males and three females)completed four simulated sprints, two CON and two experimentalrinse protocols, CHO solution and placebo (PLA).Time to completion was not different with CHO compared with CON or PLA (203.0 ±16.5 sec, 202.3 ± 15.7 sec, 203.3 ± 14.6respectively.p >.05).Mean power output was CON 264 ± 73, PLA 258 ± 65, CHO 261± 70.Blood lactateat 15 minweresimilar between CHO, CON and and PLA(9.9 ± 3.9 mmol 7.6 ± 4.0 mmol, 10.1 ± 3.7 mmol respectively.p >.05).We concludethat mouth rinsing a CHO solutionfor 10 sechave no effect on high intensity exercise with duration lasting between 3 and 4 minutes.

Title of the thesis: Current concepts of double poling by classic technique in cross-country skiing Object of the thesis: The spatial-temporal analysis of node points and kinetic phases of the kick double poling and double poling of selected competitors at the FIS Nordic World Ski Championships in Liberec 2009. Method: A case study in which we used the kinematographic method for the analysis of the kick double poling and double poling of selected competitors. We analyzed the video of the 15-km classic in the FIS Nordic World Ski Championships in Liberec 2009. For the analysis we used the software APAS. Results: We performed spatial-temporal description of node points and kinetic phases of the kick double poling and double poling of selected competitors. We characterized current concepts of kick double poling technique, because selected competitors were relatively homogeneous set. By double poling we found out flexion-extension pattern in elbow, hip joints of slipping lower limb and partly in knee and ankle joints of slipping lower limb which results in generation of great propulsive force. Double poling becomes more significant driving element than push-off. Keywords: cross-country skiing, kick double poling, double poling, kinematic analysis, top competitors

KRATKY, Jakub. Monitoring the activation of selected muscle groups of clients with spinal cord injuries. Prague: Charles University, Faculty of Physical Education and Sport, 2013. 82 pages. Supervisor Doc. PaedDr. Karel Jelen, CSc The aim of this thesis is to monitor the activation of selected muscle groups (musculus deltoideus pars anterior, musculus deltoideus pars posterior, musculus triceps brachii caput laterale and musculus trapezius pars descendus) during double poling ergometry. Nine subjects with different spinal cord lesions volunteered to participate in the study. The surface electromyography is used to detect the musculus activation. The monitoring of four muscle groups is devided into three phases. Firstly, all the participants double-poled for one minute at moderate intensity according to the Borg scale. Each participant underwent a 10-minute intervention to correct the posture. In the last phase the volunteers exercised again for one minute at moderate intensity. The aim of the intervention is to decrease muscle activation of musculus deltoideus pars anterior and musculus trapezius pars descendus (muscles with a tendency to hypertonia during wheelchair propulsion and activity of daily living) and to increase muscle activation of musculus deltoideus pars posterior and musculus triceps...

Syfte Studien syftar till att klarlägga hur stavisättningen och stakfasen påverkas vid användandet av en böjd jämfört med en rak stavdesign vid stakning i hög hastighet på rullskidor på rullband. Följande frågeställningar har undersökts:  Leder en böjd stavdesign till att stavisättningen sker längre fram?  Leder en böjd stavdesign till att stakfasens absoluta längd förändras?  Leder en böjd stavdesign till att stakfasens relativa längd förändras? Metod Tio manliga längdskidåkare (ålder 25,3 ± 5,1 år, kroppslängd 182,1 ± 8,6 cm, kroppsvikt 78 ± 6,5 kg) deltog i studien. Forskningspersonerna genomförde ett Vmax-protokoll stakning på rullskidor på rullband, med rak såväl som med böjd stavdesign. Rörelsedata samlades in och analyserades för att fastställa eventuella skillnader i stavisättning, stakfas, återförandefas och total cykeltid. Resultat En signifikant skillnad kan påvisas gällande stavisättning, där en böjd stavdesign leder till en stavisättning längre framför bindningen jämfört med en rak stavdesign. Ingen signifikant skillnad kan påvisas rörande stakfasen, återförandefasen eller total cykeltid. Slutsatser Studiens visar att stavspetsens rörelsebana flyttas vid nyttjande av en böjd stavdesign i riktning framåt. Dock påverkas inte stakfasen, återförandefasen eller total cykeltid, vilket innebär att stakfasens längd, i absoluta såväl som relativa termer, är densamma vid stakning med rak och böjd stavdesign. / Purpose statement The purpose of the study is to examine how the pole plant and pole phase are affected by using a pole of curved, compared to straight, design for double poling at high speed on roller skis at a treadmill. The following research questions have been examined:  Does a curved pole design result in a pole plant further forward?  Does a curved pole design result in a change in the absolute length of the pole phase?  Does a curved pole design result in a change in the relative length of the pole phase? Methodology Ten male cross country skiers (age 25,3 ± 5,1 years, height 182,1 ± 8,6 cm, BW 78 ± 6,5 kg) took part in the study. The test subjects performed a Vmax-test double poling on roller skis on a treadmill, with straight and curved poles. Movement data was collected and analysed to examine potential differences regarding pole plant, pole phase, recovery phase and total cycle time. Results A significant difference was found regarding the pole plant, as a curved pole design resulted in a pole plant further forward compared to a straight design. No significant difference was found related to the pole phase, recovery phase or total cycle time. Conclusion The study shows that the path of the pole tip is moved forward when using poles of a curved design. There is no change in the pole phase, the recovery phase or the total cycle time, thus the length of the pole phase, absolute as well as relative, is unaffected by pole design when double poling.

Introduction Researchers have, for decades, contributed to an increased collective understanding of the physiological demands in cross-country skiing; however, almost all of these studies have used either non-elite subjects and/or performances that emulate cross-country skiing. To establish the physiological demands of cross-country skiing, it is important to relate the investigated physiological variables to the competitive performance of elite skiers. The overall aim of this doctoral thesis was, therefore, to investigate the external validity of physiological test variables to determine the physiological demands in competitive elite cross-country skiing. Methods The subjects in Study I – IV were elite male (I – III) and female (III – IV) cross-country skiers. In all studies, the relationship between test variables (general and ski-specific) and competitive performances (i.e. the results from competitions or the overall ski-ranking points of the International Ski Federation (FIS) for sprint (FISsprint) and distance (FISdist) races) were analysed. Test variables reflecting the subject’s general strength, upper-body and whole-body oxygen uptake, oxygen uptake and work intensity at the lactate threshold, mean upper-body power, lean mass, and maximal double-poling speed were investigated. Results The ability to maintain a high work rate without accumulating lactate is an indicator of distance performance, independent of sex (I, IV). Independent of sex, high oxygen uptake in whole-body and upper-body exercise was important for both sprint (II, IV) and distance (I, IV) performance. The maximal double-poling speed and 60-s double-poling mean power output were indicators of sprint (IV) and distance performance (I), respectively. Lean mass was correlated with distance performance for women (III), whereas correlations were found between lean mass and sprint performance among both male and female skiers (III). Moreover, no correlations between distance performance and test variables were derived from tests of knee-extension peak torque, vertical jumps, or double poling on a ski-ergometer with 20-s and 360-s durations (I), whereas gross efficiency while treadmill roller skiing showed no correlation with either distance or sprint performance in cross-country skiing (IV). Conclusion The results in this thesis show that, depending on discipline and sex, maximal and peak oxygen uptake, work intensity at the lactate threshold, lean mass, double-poling mean power output, and double-poling maximal speed are all externally valid physiological test variables for evaluation of performance capability among elite cross-country skiers; however, to optimally indicate performance capability different test-variable expressions should be used; in general, the absolute expression appears to be a better indicator of competitive sprint performance whereas the influence of body mass should be considered when evaluating competitive distance performance capability of elite cross-country skiers.

Title: Individualization of pre-race microcycle for cross-country skiers Objectives: The aim of the thesis was to estimate the appropriate load of selected competitors before the competition. Methods: The work is conceived as a case study. It is a quantitative research based on measured values obtained from the trainer Ercolina Upper Body Power. We estimated the appropriate load in pre-race microcycle of five elite cross-country skiers. Results: Collected data have prevented the pre-race microcycle to be identical for all competitors. We achieved microcycle individualization for each competitor, which lead to better physical and psychological preparedness. Keywords: cross-country skiing, double poling, load, simulator, heart rate

Syfte Undersöka biomekaniska och fysiologiska skillnader mellan modern och gammeldags stakteknik vid konstant submaximalt arbete på rullskidor. Metod Tolv manliga elitskidåkare rekryterades till studien (ålder: 21 ± 4 år, längd: 183,6 ± 9,3 cm, och vikt: 77,8 ± 10,3 kg). Efter en standardiserad uppvärmning genomfördes två deltester, om fyra minuter vardera, i modern och gammeldags stakning med en individanpassad hastighet och lutningen 2,5°. Syreförbrukningen och ventilation analyserades under testen och efter varje deltest togs ett laktatprov och skattning av ansträngning utifrån Borgs RPE. Testerna filmades, där vinklar sedan plockades ut i ett videoanalysprogram. De olika testvärdena analyserade sedan med Paired samples t-test samt Paired samples Wilcoxon signed-ranked test. Resultat Ingen signifikant skillnad påvisades mellan modern och gammeldags stakning för syreförbrukning, energiförbrukning, rörelseekonomi, andningsfrekvens samt laktathalt. Signifikanta skillnader påvisades för hjärtfrekvens, ventilation, respiratory exchange ratio (RER) samt Borg RPE, där gammeldags stakning uppvisade högre värden för samtliga variabler förutom RER. Även i en del ledvinklar samt för tiden i den kraftskapande- och återhämtningsfasen stakcyklerna och tyngdpunktsförflyttningen. Slutsatser Studien visar inga signifikanta skillnader i energikostnad, syrekonsumtion, rörelseekonomi samt blodlaktatskoncentration mellan modern och gammeldags stakning vid submaximalt arbete. Däremot finns signifikanta skillnader i hjärtfrekvens, ventilation samt den skattade tröttheten som tyder på att gammeldags stakning upplevs något mer ansträngande. Framtida forskning behövsför att avgöra om detta skiljer sig i annan lutning och hastighet. / Purpose Examine whether biomechanical and physiological variables differ between modern and old-fashioned double poling technique (OFDP) at a constant submaximal work rate during roller skiing. Methods Twelve male elite cross-country skiers were recruited (age: 21 ± 4 years, length: 183,6 ± 9,3 cm, and weight: 77,8 ± 10,3 kg). After a standardized two subtests followed, in modern and OFDP technique at an individual velocity and the incline 2,5°. Oxygen consumption and ventilation were measured during the testand lactate concentration as well as estimation of Borg RPE were measuredafter every subtest. The test was recorded and angles were analysed. Test values were analysed using Paired samples t-test as well as Paired samples Wilcoxon signed-ranked test. Results No significant difference in energy expenditure (EE), O2 consumption, gross efficiency (GE), breathing frequency (BF) and lactate were shown. Significant differences were shown between heart rate (HR), ventilation, RER and Borg RPE, where higher values were shown for OFDP at all variables except RER. Significant differences were shown in some joint angles as well as the time of the power creating phase,returning phase of the pole stroke and the centre of mass (COM) displacement. Conclusions No significant difference in EE, O2 consumption, GE and lactate between modern and OFDP during a submaximal work rate. Differences in HR and estimated exhaustion gives a hint of the OFDP being more exhausting. Future research is required to determine if this differs in other inclines and velocities.

Introduction Performance in cross-country skiing is influenced by the skier’s ability to continuously produce propelling forces and force magnitude in relation to the net external forces. A surrogate indicator of the “power supply” in cross-country skiing would be a physiological variable that reflects an important performance-related capability, whereas the body mass itself is an indicator of the “power demand” experienced by the skier. To adequately evaluate an elite skier’s performance capability, it is essential to establish the optimal ratio between the physiological variable and body mass. The overall aim of this doctoral thesis was to investigate the importance of body-mass exponent optimization for the evaluation of performance capability in cross-country skiing. Methods In total, 83 elite cross-country skiers (56 men and 27 women) volunteered to participate in the four studies. The physiological variables of maximal oxygen uptake (V̇O2max) and oxygen uptake corresponding to a blood-lactate concentration of 4 mmol∙l-1 (V̇O2obla) were determined while treadmill roller skiing using the diagonal-stride technique; mean oxygen uptake (V̇O2dp) and upper-body power output (Ẇ) were determined during double-poling tests using a ski-ergometer. Competitive performance data for elite male skiers were collected from two 15-km classical-technique skiing competitions and a 1.25-km sprint prologue; additionally, a 2-km double-poling roller-skiing time trial using the double-poling technique was used as an indicator of upper-body performance capability among elite male and female junior skiers. Power-function modelling was used to explain the race and time-trial speeds based on the physiological variables and body mass. Results The optimal V̇O2max-to-mass ratios to explain 15-km race speed were V̇O2max divided by body mass raised to the 0.48 and 0.53 power, and these models explained 68% and 69% of the variance in mean skiing speed, respectively; moreover, the 95% confidence intervals (CI) for the body-mass exponents did not include either 0 or 1. For the modelling of race speed in the sprint prologue, body mass failed to contribute to the models based on V̇O2max, V̇O2obla, and V̇O2dp. The upper-body power output-to-body mass ratio that optimally explained time-trial speed was Ẇ ∙ m-0.57 and the model explained 63% of the variance in speed. Conclusions The results in this thesis suggest that V̇O2max divided by the square root of body mass should be used as an indicator of performance in 15-km classical-technique races among elite male skiers rather than the absolute or simple ratio-standard scaled expression. To optimally explain an elite male skier’s performance capability in sprint prologues, power-function models based on oxygen-uptake variables expressed absolutely are recommended. Moreover, to evaluate elite junior skiers’ performance capabilities in 2-km double-poling roller-skiing time trials, it is recommended that Ẇ divided by the square root of body mass should be used rather than absolute or simple ratio-standard scaled expression of power output. / <p>Incorrect ISBN in printed thesis: 973-91-7601-270-3</p>

Introduction Researchers have, for decades, contributed to an increased collective understanding of the physiological demands in cross-country skiing; however, almost all of these studies have used either non-elite subjects and/or performances that emulate cross-country skiing. To establish the physiological demands of cross-country skiing, it is important to relate the investigated physiological variables to the competitive performance of elite skiers. The overall aim of this doctoral thesis was, therefore, to investigate the external validity of physiological test variables to determine the physiological demands in competitive elite cross-country skiing. Methods The subjects in Study I – IV were elite male (I – III) and female (III – IV) cross-country skiers. In all studies, the relationship between test variables (general and ski-specific) and competitive performances (i.e. the results from competitions or the overall ski-ranking points of the International Ski Federation (FIS) for sprint (FISsprint) and distance (FISdist) races) were analysed. Test variables reflecting the subject’s general strength, upper-body and whole-body oxygen uptake, oxygen uptake and work intensity at the lactate threshold, mean upper-body power, lean mass, and maximal double-poling speed were investigated. Results The ability to maintain a high work rate without accumulating lactate is an indicator of distance performance, independent of sex (I, IV). Independent of sex, high oxygen uptake in whole-body and upper-body exercise was important for both sprint (II, IV) and distance (I, IV) performance. The maximal double-poling speed and 60-s double-poling mean power output were indicators of sprint (IV) and distance performance (I), respectively. Lean mass was correlated with distance performance for women (III), whereas correlations were found between lean mass and sprint performance among both male and female skiers (III). Moreover, no correlations between distance performance and test variables were derived from tests of knee-extension peak torque, vertical jumps, or double poling on a ski-ergometer with 20-s and 360-s durations (I), whereas gross efficiency while treadmill roller skiing showed no correlation with either distance or sprint performance in cross-country skiing (IV). Conclusion The results in this thesis show that, depending on discipline and sex, maximal and peak oxygen uptake, work intensity at the lactate threshold, lean mass, double-poling mean power output, and double-poling maximal speed are all externally valid physiological test variables for evaluation of performance capability among elite cross-country skiers; however, to optimally indicate performance capability different test-variable expressions should be used; in general, the absolute expression appears to be a better indicator of competitive sprint performance whereas the influence of body mass should be considered when evaluating competitive distance performance capability of elite cross-country skiers.

Introduction Performance in cross-country skiing is influenced by the skier’s ability to continuously produce propelling forces and force magnitude in relation to the net external forces. A surrogate indicator of the “power supply” in cross-country skiing would be a physiological variable that reflects an important performance-related capability, whereas the body mass itself is an indicator of the “power demand” experienced by the skier. To adequately evaluate an elite skier’s performance capability, it is essential to establish the optimal ratio between the physiological variable and body mass. The overall aim of this doctoral thesis was to investigate the importance of body-mass exponent optimization for the evaluation of performance capability in cross-country skiing. Methods In total, 83 elite cross-country skiers (56 men and 27 women) volunteered to participate in the four studies. The physiological variables of maximal oxygen uptake (V̇O2max) and oxygen uptake corresponding to a blood-lactate concentration of 4 mmol∙l-1 (V̇O2obla) were determined while treadmill roller skiing using the diagonal-stride technique; mean oxygen uptake (V̇O2dp) and upper-body power output (Ẇ) were determined during double-poling tests using a ski-ergometer. Competitive performance data for elite male skiers were collected from two 15-km classical-technique skiing competitions and a 1.25-km sprint prologue; additionally, a 2-km double-poling roller-skiing time trial using the double-poling technique was used as an indicator of upper-body performance capability among elite male and female junior skiers. Power-function modelling was used to explain the race and time-trial speeds based on the physiological variables and body mass. Results The optimal V̇O2max-to-mass ratios to explain 15-km race speed were V̇O2max divided by body mass raised to the 0.48 and 0.53 power, and these models explained 68% and 69% of the variance in mean skiing speed, respectively; moreover, the 95% confidence intervals (CI) for the body-mass exponents did not include either 0 or 1. For the modelling of race speed in the sprint prologue, body mass failed to contribute to the models based on V̇O2max, V̇O2obla, and V̇O2dp. The upper-body power output-to-body mass ratio that optimally explained time-trial speed was Ẇ ∙ m-0.57 and the model explained 63% of the variance in speed. Conclusions The results in this thesis suggest that V̇O2max divided by the square root of body mass should be used as an indicator of performance in 15-km classical-technique races among elite male skiers rather than the absolute or simple ratio-standard scaled expression. To optimally explain an elite male skier’s performance capability in sprint prologues, power-function models based on oxygen-uptake variables expressed absolutely are recommended. Moreover, to evaluate elite junior skiers’ performance capabilities in 2-km double-poling roller-skiing time trials, it is recommended that Ẇ divided by the square root of body mass should be used rather than absolute or simple ratio-standard scaled expression of power output. / <p>Incorrect ISBN in printed thesis: 973-91-7601-270-3</p>