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Umetnostno kotalkanje je tekmovalna športna panoga, pri kateri tekmovalci uporabljajo posebne čevlje s pritrjenimi majhnimi kolesci z zavoro spredaj, s katerimi se premikajo v športnih dvoranah ali zunaj na betonskih površinah. Športniki lahko tekmujejo v različnih disciplinah, osredotočili pa smo se na disciplino prostega kotalkanja v starostni kategoriji kadetov. Značilnost te discipline je izpopolnjeno znanje določenih tehničnih elementov, ki so skoki, piruete in koraki. Ti elementi se povezujejo v tekmovalni program, njihova izvedba pa se mora skladati z ritmom in temo individualno izbrane glasbo. Kadeti spadajo v obdobje mladostništva in pubertete, ki ima svojevrstne značilnosti in potrebe v procesu načrtovanja programa za izboljšanje telesne pripravljenosti v določeni športni panogi. Temeljni namen magistrskega dela je bil z deskriptivno metodo dela temeljito raziskati sodobni model umetnostnega kotalkarja in področja njegove telesne priprave v kadetski kategoriji. Oblikovani cilji so bili opredelitev gibalnih in aerobnih sposobnosti, ki jih je treba razvijati v umetnostnem kotalkanju in jih umestiti v kontekst discipline prostega kotalkanja v omenjeni starostni kategoriji ter oblikovati periodizacijo trenažnega procesa tekom sezone. Kadeti morajo v tem obdobju izboljševati predvsem razvoj odrivne moči, specifične vzdržljivosti, specifične koordinacije in gibljivosti. S proučevanjem domače in tuje literature na področju razvoja človeškega organizma, programiranja telesne priprave ter raziskav s področja umetnostnega kotalkanja in umetnostnega drsanja smo tako pripravili letni načrt za izboljšanje telesne priprave v kadetski kategoriji. To delo naj bi bilo v pomoč trenerjem, ki stremijo h kakovostnemu delu z mladimi. Artistic roller skating is a competitive sports discipline in which the competitors are using specific skating shoes, attached to a plate with small wheels and with a break in the front for movement in sports halls or outside on concrete surfaces. Skaters can compete in different disciplines but the focus of the thesis is the discipline of free skating in cadet category. The main feature of free skating is improved proficiency of certain technical elements which are jumps, spins and steps. These elements are connected into a programme while their execution has to match with the rhythm and theme of the individually chosen music. Cadets belong in the phase of adolescence and puberty which has its own characteristics and needs in the process of planning a programme for improvement of physical preperation in particular sports discipline. The fundamental purpose of the thesis, with the use of a descriptive method, was a thorough research of a profound model of an artistic roller skater and areas of their physical preperation in cadet category. Formed goals were definitions of motor and aerobic abilities which need to be developed in artistic roller skating and inducted to context of free skating discipline in mentioned category and design of periodization of sport program during the season. Cadets should strive to improve predominantly development of take-off power, specific endurance, specific coordination and flexibility. Based on the domestic and foreign literature in the field of human development, physical preperation planning and research in the field of artistic roller skating and figure skating, we prepared an annual plan for improvement of physical preperation in cadet category. The programme is designed for all coaches who aim at high-quality work with the youth.

Educators and health professionals need to gain knowledge of the special needs of artistic roller skaters if they seek effective training and preventing physical complaints or injuries. In the absence of epidemiological studies on artistic roller skaters, it is useful to characterize the participants, their participation habits, and the occurrence of physical complaints or injuries. A web-based survey was designed to collect epidemiological information on female artistic roller skaters. The self-report questionnaire included information about the participant, her participation habits, injury history, and physical complaints in the past 12 months. A total of 143 female artistic roller skaters were included in the study. Sixty-seven [46.9%] of the participants had 175 physical complaints in the past 12 months, for an average of 2.61 complaints per skater. The physical complaints mainly affected the lower limbs (53.1%), followed by the trunk (24.0%) and upper limbs (22.9%). The most affected sites were the knee (16.6%), back (10.9%) and wrist (10.3%). Our results suggest that physical complaints are common in artistic roller skating. It becomes crucial to study the etiology of physical complaints and/or injuries. Preventing physical complaints and injuries is crucial for athletes’ well-being. Our study results may draw attention and help coaches and educators implement adequate preventive measures. Los educadores y profesionales de la salud deben conocer las necesidades especiales de los patinadores artísticos sobre ruedas si buscan un entrenamiento eficaz y previenen quejas o lesiones físicas. En ausencia de estudios epidemiológicos sobre patinadores artísticos, es útil caracterizar a los participantes, sus hábitos de participación y la ocurrencia de quejas o lesiones físicas. Se diseñó una encuesta basada en la web para recopilar información epidemiológica sobre patinadoras artísticas femeninas. El cuestionario de autoinforme incluía información sobre la participante, sus hábitos de participación, historial de lesiones y quejas físicas en los últimos 12 meses. Se incluyeron en el estudio un total de 143 patinadoras artísticas femeninas. Sesenta y siete [46,9%] de los participantes tuvieron 175 quejas físicas en los últimos 12 meses, con un promedio de 2,61 quejas por patinador. Las quejas físicas afectaron principalmente a los miembros inferiores (53,1%), seguido del tronco (24,0%) y miembros superiores (22,9%). Los sitios más afectados fueron rodilla (16,6%), espalda (10,9%) y muñeca (10,3%). Nuestros resultados sugieren que las quejas físicas son comunes en el patinaje artístico sobre ruedas. Se vuelve crucial estudiar la etiología de las molestias y/o lesiones físicas. La prevención de molestias y lesiones físicas es crucial para el bienestar de los atletas. Los resultados de nuestro estudio pueden llamar la atención y ayudar a los entrenadores y educadores a implementar medidas preventivas adecuadas. Actividad Física y Deporte

Figure skating is an increasingly popular sport in Portugal, with a growing number of athletes involved. It is therefore imperative, to closely monitor any anomaly that may exist. The accumulation of data from the championship results and the fact that no studies have been done before with the results of Figure Skating on wheels, makes it an advantage to do it now. Since the Skating judging system is in a transition period, it is important to understand what was the comportment of the last few years, so that it can be compared later with the new system to be implemented. For the development of this dissertation, a problem was identified and analyzed through data mining techniques and statistical tests, in order to achieve results that prove if there is a problem with the current judging system. The overall problem identified was the final results obtained by athletes in European Championships of the last 8 years. As mentioned above, data mining techniques were used, more precisely a sensitivity analysis model was constructed. Data used as input to the sensitivity model and statistical tests were provided by the Federação de Patinagem de Portugal. To define some metrics such as when an athlete’s results are biased, the feedback was collected from coaches and judges. With this dissertation, it was possible to realize that there is a relationship between the final position of the athlete and the place where the championship takes place, as well as the nationality of the judge and the athlete. However, it is not possible to support the origin of the bias identified in the results once it can be unconscious. A patinagem artística é um desporto cada vez mais popular em Portugal, com cada vez mais atletas envolvidos. É, portanto, relevante acompanhar de perto qualquer eventual erro no processo de avaliação dos atletas nas competições internacionais. O acumular de dados dos resultados de campeonatos e o facto de até ao momento não ter sido feito nenhum estudo sobre as avaliações dos juízes em competições de Patinagem Artística sobre rodas, faz com que seja uma mais valia fazê-lo agora. Uma vez que o sistema de ajuizamento da patinagem se encontra em período de transição, é importante perceber qual foi o comportamento dos últimos anos, para mais tarde ser possível fazer uma comparação com o novo sistema a ser implementado. Para o desenvolvimento desta dissertação foi identificado um possível problema (enviesamento na atribuição de notas em competições internacionais), sendo este analisado através de técnicas de Data Mining e testes estatísticos. O objetivo é o de se encontrarem resultados que comprovem se se está realmente perante alguma falha no sistema de ajuizamento. Foram analisados os resultados finais obtidos pelos atletas em Campeonatos da Europa dos últimos 8 anos. Tal como referido acima, foram utilizadas técnicas de Data Mining, mais precisamente foi construído um modelo de análise de sensibilidade. Os dados utilizados como input do modelo de sensibilidade e dos testes estatísticos foram fornecidos pela Federação de Patinagem de Portugal. Para se definir algumas métricas tais como, quando é que se poderia considerar que um atleta teria o seu lugar enviesado, foram consultados treinadores e juízes. Com esta dissertação foi possível detetar que existe relação entre a posição final do atleta e o local onde decorre o campeonato, assim como a nacionalidade do juiz e do atleta. Contudo, não é possível afirmar a origem do enviesamento identificado nos resultados, isto é, se o enviesamento é intencional ou não.

Introduction Knowing the biomechanical key factors of each jump is fundamental for figure skating coaches in order to more effectively teach triple jumps to their athletes. Notwithstanding the number of studies on ice skating (King et al., 2004), no biomechanical jump analysis, to the knowledge of the present authors, performed on roller skating. The purpose of the present study was to compare some kinematic characteristics of double and triple Lutz jumps in roller skating. Methods 5 elite male skaters performing a series of double and triple Lutz were acquired using 10 infrared cameras (Smart-D, BTS, Milan, Italy, 250 Hz). For the trunk, the upper limbs and the foot segments, markers were attached directly on specific anatomical landmarks. For the thigh and the shank segments, the calibrated anatomical system technique was exploited (Cappozzo et al., 1995). The resultant velocity angle was also considered. Five key events were identified for each jump: toe-pick (instant in which the toe-pick impacted the ground), end of gliding (last contact of the left foot), take-off (last contact of the right foot), maximum height (top of the flight phase), and landing (instant of contact with the ground). Results The hip and the knee were flexed at the toe-pick, whereas the flexion was clearly lower at the take-off. On the contrary, the ankle at toe-pick was in the neutral position, and plantarflexed at the take-off, but differently depending on the skater. The skaters’ horizontal velocities at take-off for the triple Lutz (mean: 2.69 m/s) were lower than those for the double one (mean: 3.17 m/s). Vertical velocities at take-off showed slightly higher values for the triple (mean: 2.90 m/s) compared to the double (mean: 2.72 m/s) Lutz. The average resultant velocity angle in the 5 athletes was 40° in the double and 47° in the triple Lutz, at the take-off. The greatest difference between the double and triple jumps was the rotational velocity during the flight estimated from the rotation of the pelvis segment. The pelvis rotation velocity was higher in the triple Lutz already during the toe pick (means: 0.84 rev/s for double and 1.75 rev/s for triple one). Jumping height and flight time were higher for the triple jump for three skaters. Discussion For the first time a biomechanical comparison between the double and the triple Lutz in roller skating was performed. Some of these findings were already roughly known to coaches and skaters, but only in the present study some specific descriptors of the jump were characterized and quantified. References King D, Smith S, Higginson B, Muncasy B, Scheirman G. (2004). Sports Biomechanics, 3, 109-123. Cappozzo A, Catani F, Della Croce U, Leardini A. (1995). Clinical Biomechanics, 10, 171-178.

In artistic roller skating, there are no quantitative biomechanical studies analysing the Lutz. Therefore, the aim of this research was to analyse the kinematic of the Triple Lutz in world-class athletes. Five subjects were analysed. A motion analysis system was used to reconstruct the position of apposite markers placed on the athlete’s body and on the skate. Relevant biomechanical indices representing linear and angular displacements, angular velocities were analysed in different phases of the considered movement. The pelvis centre raised on average of 25.4 cm at the take-off (range: 19.5 – 34.8 cm). The mean height of the flight trajectory was of 50.5 cm (range: 42.2 – 57.8 cm). The absolute distance between the pelvis centre and the right foot centre at the toe assist was 50.1 cm, whereas at the take-off it was 13.5 cm, i.e. definitely lower, with very wide oscillations between the minimum (2.6 cm) and the maximum (23.6 cm) value. The left knee and the ankle, at the toe assist, were clearly flexed (knee: 62° and ankle: 24° of dorsiflexion). Then, the knee showed the maximum extension in correspondence with the take-off of the left skate (12°). In the same instant, the left ankle showed a moderate plantarflexion of 19°. At the take-off of the right foot, the left knee showed a slight flexion (24°), whereas the ankle showed a little flexion (21°). The inclination of the trunk was more pronounced at the toe assist (37°), and less marked in the following phases (end of the gliding: 32°, and take-off: 28°). The peak velocity varied from 4.72 m/s (recorded before the toe assist) to 4.18 m/s. Then, the velocity further reduced at the take-off of the gliding skate (2.71 m/s), and at the take-off of the jump it is 2.69 m/s. Therefore, the horizontal speed at the end of the gliding was almost equal to that at the take-off. It is possible to explain what described about the pelvis motion by analysing the lower limbs kinematics. The toe assisting leg joints showed a loading action just after the toe assist, that was very little for the hip, moderate for the knee (6°), more pronounced for the ankle (21°). The loading time was the shortest for the knee (0.027 s) and the longest for the ankle (0.09 s). Considering the falling time of the pelvis (0.04 s), it can be concluded that the fall is related to the loading of all the three joints of the toe assisting leg. The gliding leg, at the toe assist, was in the neutral position on the frontal plane, whereas it was markedly flexed such as the knee and the ankle. Then, the three joints made an extension movement, continuing up to the end of the gliding phase. The latero-lateral movements (adduction – abduction) of the hips were less evident in the initial phase for the gliding. Concerning the trunk movements, the subjects showed different strategies about the hip and shoulder movements in the toe assist and take-off points. The upper limbs movements in the toe assist and take-off phases were very different amongst the examined subjects. Therefore, it is not possible to individuate a reference model that can provide useful for a general analysis. In the future, a qualitative analysis of the arms movements will be carried out to understand the different strategies adopted by the various athletes.