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Uzturs Veselības aprūpe Nutrition Health Care Bakalaura darba nosaukums: Kreatīna monohidrāta un beta alanīna akūto devu ietekme uz Latvijas sprinta distanču peldētāju rezultātiem. Bakalaura darba autors: Reinis Eduards Paulis, Rīgas Stradiņa universitātes, Rehabilitācijas fakultātes, profesionālās bakalaura studiju programmas “Uzturs” students. Pētījuma mērķis: noskaidrot kreatīna monohidrāta un beta alanīna akūto ietekmi uz Latvijas sprinta distanču peldētāju rezultātiem. Pētījuma aktualitāte: Reālas atšķirības sportiskajā sniegumā sacensībās lielākoties ir nenozīmīgas, un tas veicina sporta uztura bagātinātāju izmantošanu. Kreatīns ir viens no visbiežāk lietotajiem uztura bagātinātājiem, jo ir pierādīts, ka tas ir labvēlīgs veiktspējas uzlabošanai atkārtotas augstas intensitātes anaerobās aktivitātes laikā. Kā arī pētījumi par beta alanīna uzņemšanu liecina par ietekmi uz vielmaiņas (aerobās un anaerobās) līdzdalību un peldēšanas veiktspējas uzlabošanu. Lai gan ir veikti vairāki pētījumi par kreatīna monohidrāta un beta alanīna izolēto iedarbību peldēšanā, nav skaidrs, kāda ir to ietekme, ja tos apvieno. Pētījuma metodes: Pētījums veikts Rīgas Ķīpsalas peldēšanas klubā (Ķīpsalas iela 5, Rīga). Tika iesaistīti Latvijas Peldēšanas federācijas peldētāji, kuri piedalās sprinta distancēs (50 m, 100 m). Divdesmit četri peldētāji, vīrieši, vecumā no 19 līdz 26 gadiem aizpildīja aptaujas anketas. Tajās tika ietverti dati par respondentu, izpratne par uztura bagātinātājiem un to lietošanas paradumiem. Pētījuma dalībnieki piedalījās četros fiziskajos peldēšanas testos, kuros akūti uzņēma kreatīna monohidrāta un beta alanīna uztura bagātinātājus un veica četrus atkārtotus peldējumus pa 25 metriem, kuros tika fiksēts laiks. Fiziskos peldēšanas testus atkārtoja četras reizes ar vienas nedēļas intervālu starp tiem. Datu salīdzināšanai tika izmantotas neparametriskās statistikas metodes. Vērtības tika uzskatītas par statistiski ticamām, ja p < 0,05. Rezultāti un secinājumi: Veicot atkārtotus sprinta fizikālos peldēšanas testus, tika novērota pozitīva ietekme kreatīna monohidrāta un beta alanīna akūto devu papildināšanai uz sprinta distanču peldētāju rezultātiem, kur uzlabojums rezultātā bija redzams visās trijās dalībnieku grupās. Var pieņemt, ka abu uztura bagātinātāju kombinācija samazināja pienskābes veidošanos muskuļos un nodrošināja papildu enerģiju fizikālo peldēšanas testu laikā. Rezultātu praktiskā pielietojamība: Pētījuma rezultāti sniegs informāciju par kreatīna monohidrāta un beta alanīna akūto devu ietekmi uz Latvijas sprinta distanču peldētāju rezultātiem. Iegūtos rezultātus varēs izmantot Latvijas Peldēšanas federācija, t. sk., Latvijā esošās sporta skolas un klubi, lai uzlabotu peldētāju rezultātus. Title: Effects of acute doses of creatine monohydrate and beta-alanine on the performance of sprint distance swimmers. Author: Reinis Eduards Paulis, student of professional study programme “Nutrition”, Faculty of Rehabilitation, Riga Stradiņš university. Aim of research: to find out the acute effects of creatine monohydrate and beta-alanine on the performance of Latvian sprint distance swimmers. Topicality of research: Real-world differences in athletic performance in competition are largely insignificant, this encourages the use of sports supplements. Creatine is one of the most commonly used nutritional supplements, it has been shown to benefit performance during repetitive high-intensity anaerobic activity. Also, studies on beta-alanine intake show effects on metabolic (aerobic and anaerobic) participation and improved swimming performance. Although there have been several studies on the isolated effects of creatine monohydrate and beta-alanine in swimming, it is not clear what their effects are when combined. Methods: The research was carried out in the Riga Ķipsalas swimming club (Ķipsalas iela 5, Riga). In this study were involved swimmers of Latvian Swimming Federation who participate in sprint distances (50 m, 100 m). A survey was conducted, which was completed by 24 swimmers (men; age: 19 - 26 years). A questionnaire was used to survey the athletes. It was compiled using questionnaires by other authors, validating the questions for this study. Study participants participated in four physical swimming tests in which they acutely ingested creatine monohydrate and beta-alanine supplements and performed four repeated 25-meter swims that were timed. Physical swimming tests were repeated four times with an interval of one week between them. Non-parametric statistical methods were used to compare the data. Values were considered statistically significant at p < 0.05. Results and conclusions: During sprint physical swimming test, a positive effect of acute creatine monohydrate and beta-alanine supplementation on the performance of sprint distance swimmers was observed, where the resulting improvement was evident in all three participant groups. It can be assumed that the combination of both supplements reduced the production of lactic acid in the muscles and provided additional energy during physical swimming tests. Practical use of results: The results of the study will provide information about the effect of acute doses of creatine monohydrate and beta alanine on the results of Latvian sprint distance swimmers. The obtained results will be able to be used by the Latvian Swimming Federation, including sports schools and clubs in Latvia, to improve the results of swimmers.

Prior research suggests interorganizational collaboration faces temporal challenges and also opportunities yet is scarce on the role of time enabling—more often deterring—collaboration for collective benefit. Our contribution is highlighting how a large industry–academic research network developed temporally complex collaboration through varying temporal rules and relationships. The three network-developed collaborative repertoires, with their particular temporal rules and relationships, complemented the externally imposed calendar repertoire: (1) sprint repertoire, following a familiar agile method for joint research, (2) narrative time repertoire, enabling sharing research results across various events at the program level, and (3) “right” time repertoire that turned research results into action in emerging business ecosystems. With these collaborative repertoires, both the temporal diversities of home organizations and the asynchronies of the network activities were resolved for collective benefit. We contribute to the intersection of the literatures on interorganizational network collaboration and temporality.

The industrial development of technology, with appropriate adaptation, enables us to discover possibilities in sport training control. Therefore, we have developed a new approach to linear running analysis. This study aims to determine the measurement possibilities using an LDM301A laser system in obtaining basic kinematic parameters. The second goal is the application of specialized computer programs based on appropriate algorithms to calculate a vast number of variables that can be used to adjust the training and the rivalry. It is a non-invasive, non-contact measurement method. We can also determine the influence of both subjective and objective external factors. In this way, we can also conduct training with real-time scientific feedback. This method is easy to use and requires very little time to set up and use. The efficiency and running economy can be calculated with various time, speed, acceleration, and length indexes. Calculating the symmetries between the left and right leg in velocity, stride lengths, support phase times, flight phase times, and step frequency are possible. Using the laser measurement method and detailed kinematic analysis may constitute a new chapter in measuring speed. However, it still has to compete with classic photocell measurement methods. This is mainly due to their high frequency of measurement used, despite some reservations about the scale of measurement errors.

The present study attempts to assess changes in soccer players’ physical and technical activity profiles due to thermal stress, measured with the Universal Thermal Climate Index (UTCI), in training centres and during matches of the 2018 FIFA World Cup in Russia. The study also verifies the theoretical models of soccer players’ physiological parameters. The study sample consisted of 945 observations of 340 players of national teams taking part in the World Cup in Russia. The measured variables included physical activities: total distance covered, distances covered with an intensity of 20–25 km/h, number of sprints; technical activities: number of shots, number of passes, pass accuracy and physiological indicators: evaporative water loss and heart rate. In addition, the final ranking places of each national team were also used in the study. The UTCI was calculated based on meteorological data recorded at training centres and during matches. The UTCI records were then classified into two ranges: NTS—no thermal stress (UTCI 9–26 °C) and TS—thermal stress (UTCI > 26 °C). Climatic conditions at soccer training centres assessed as involving “no thermal stress” are found to be more beneficial for increasing the total distance covered and the number of sprints performed by players during a match. The theoretical models for determining soccer players’ physiological parameters used in the study reduce the players’ heart rate effort and evaporative water loss, which is in line with findings in studies by other authors. The climatic conditions at soccer training centres and during tournament matches should be taken into account in planning preparations for future World Cup tournaments, especially those in hotter countries.

The aim of the present study is to compare the effects of a (i) repeated sprint protocol on the sprint performance, hamstrings shear modulus pattern, and neuromuscular parameters between players with and without previous hamstring strain injury (HSI); and (ii) between limbs with HSI and their healthy contralateral limbs on the hamstrings shear modulus pattern and neuromuscular parameters. One-hundred-and-five professional and semiprofessional football field players were invited to participate in this study during the pre-season 2021/2022 (June–July), resulting in a sample size of 210 limbs with 46 sustaining HSI in the previous 2 years. No differences were seen between previously injured and healthy control players regarding their sprint performance, hamstrings shear modulus pattern, and neuromuscular parameters, except for the early rate of torque development (0–50 ms) with previously injured limbs in the biceps femoris long head (BFlh) displaying higher rates than their contralateral muscle (injured: 496.93 ± 234.22 Nm/s; contralateral 422.72 ± 208.29 Nm/s; p = 0.005; η2p = 0.469). Overall, the present study provides evidence for no differences regarding sprint performance, hamstrings load sharing pattern, and major neuromuscular parameters between players with previous HSI in the last 2 years and healthy control players. Therefore, the results can possibly suggest that the duration between injury and screening could recover the differences between injured-control and injured-contralateral groups.

Simple Summary Caffeine is a stimulant of the central nervous system widely utilized by many athletes to enhance endurance, strength, and power-based sports performances. Whether ergogenic enhancements following caffeine ingestion result in improvements in sports-specific skills performance has received less attention. In basketball, the ability to execute certain tasks with accuracy, such as shooting and passing, are key factors affecting the outcome of the sport. Besides being able to excel in accuracy-based tasks, the possession of strong physical attributes, including vertical jump height, sprint speed and agility, are also key components to basketball performance. In this review, an overview of the effects of caffeine on basketball-related skill tasks and physical aspects of performance deemed important for the game is provided. One of the key focal points is that the efficacy of caffeine is influenced by a multitude of determinants that have an overall impact on the ergogenic capacity of caffeine. Proper awareness of these determinants allows basketball players, coaches, and trainers to have better insights and knowledge in applying caffeine to improve basketball-related performances. Abstract Caffeine is an ergogenic aid in many sports, including basketball. This systematic review examines the effects of caffeine on basketball-related skill tasks along with physical aspects of performance deemed important for the game. A systematic search was conducted across three databases (PubMed, SPORTDiscus and Web of Science) to identify randomized-controlled trials which examined the effect of caffeine on basketball performance outcomes including: free-throw, 3-point shooting accuracy, dribbling speed, vertical jump height, and linear and repeated sprints. Forty-six articles were identified of which 10 met the inclusion criteria. Improvements in vertical jump were identified in four of five studies, agility in two of four studies, and in linear and repeated sprints in two of three studies. No deterioration in basketball skills performance was observed in any studies. It is suggested that caffeine is useful for basketball players to improve the physical aspects of their game-play performance but there is little evidence of any change in skill-based performance at present. Further research should clarify the effects of caffeine on basketball performance in women and the role of individual genetic variation on caffeine metabolism. Basketball players and coaches should be aware of the properties of caffeine before ingesting it as an ergogenic supplement.

The purpose of this study was to examine how the four best teams in the 2018 Football Men's World Cup rotate by squad and how this impact the physical activity of the teams in consecutive rounds. The study sample consisted of the 31 players of the 4 best teams, who played in every tournament match, except for the third game of the group stage. The analysis included 186 observations and was carried out on the most exploited players (MEP) excluding goalkeepers, who played at least 450 mins (5 full matches) in the tournament. The analysis was conducted using data collected by an advanced motion analysis system known as STATS®. The selected physical activity parameters analyzed included: total distance covered (m/min), distance covered at various intensity ranges (m/min), top speed (km/h), and number of sprints performed. It was found that all four teams in the third match of the group stage have performed the largest number of rotations with most exploited players and introduced the highest number of rested players (7.75 ± 2.06). A significant increase was observed between the second and fourth match in the 0–7 km/h distance covered (37.99 ± 3.19–39.23 ± 3.35 m/min) and the top speed (28.12 ± 2.22–29.21 ± 2.64 km/h)—p < 0.05. Furthermore, MEPs in the knockout stage, used pacing strategies by increasing the amount of low-intensity running to maintain high intensity during the game. From a practical point of view, this investigation shows that squad rotation can be a valuable support to a pacing strategy by players.

Orientador: Denise Vaz de Macedo Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Educação Física Resumo: O objetivo do presente estudo foi observar as adaptações promovidas pelo treinamento intervalado (TI) com diferentes tempos de pausas passivas. Vinte indivíduos fisicamente ativos, estudantes de Educação Física, foram divididos em dois grupos (G1 e G2) e submetidos a 14 sessões de TI. O protocolo de treino consistiu de sprints de 40 segundos em intensidade áxima, com pausa de 2 minutos entre os mesmos para o G1 e 5 para o G2. O volume dos sprints foi gradativamente incrementado ao longo das sessões seguindo o seguinte padrão: 4 sprints da 1ª a 3ª, 6 da 4ª a 6ª, e 8 da 7ª a 14ª sessão. Foram avaliados desempenho no teste 40 segundos (40s), as velocidades de limiar ventilatório (vLV), ponto de compensação respiratória (vPCR), e de consumo máximo de oxigênio (vVO2máx.), o consumo máximo de oxigênio (VO2máx.), composição corporal (CC), séries branca e vermelha, e a cinética de remoção do lactato frente ao 40s (CRL). A CC, CRL, série vermelha e branca foram acessadas na semana anterior ao início do programa, e uma semana após o término do mesmo (7D). A vLV, vPCR, vVO2máx, o VO2máx, e o 40s também foram acessados 14 dias após o término do programa de treinamento (14D). Como resultados observamos que os dois grupos aumentaram significativamente o desempenho no 40s em 7D e 14D; Não houve alterações significantes nas séries vermelha e branca; Três sujeitos do G1 aumentaram significantemente a vLV em 7D, enquanto que quatro não apresentaram alteração, e um diminuiu; Cinco sujeitos no G2 aumentaram significantemente a vLV no momento 7D, mas três não, sendo que um diminuiu sua vLV; Para a vPCR quatro sujeitos do G1 exibiram aumento significante, um sujeito diminuiu, e três não sofreram alterações em 7D.; Seis sujeitos no G2 exibiram maior vPCR, dois não exibiram alteração, e um diminuiu no momento 7D; A vVO2max aumentou em apenas um sujeito do G1 e não se alterou nos demais; Três sujeitos no G2 exibiram aumento na vVO2max e seis mantiveram em 7D. Levando-se em comparação os valores de erro típico inerente ao protocolo para vLV (ET=0,62km/h), vPCR (ET=0,35km/h) e vVO2max (ET=0,43km/h), podemos observar que o número de sujeitos com aumento significativo na resposta no momento 14D aumentou em todas as variáveis, sugerindo uma supercompensação dos efeitos do treino intervalado de alta intensidade nesses parâmetros após duas semanas de descanso. Não observamos alterações significantes no Tmax para G1 e G2, sem nenhuma alteração significante para o Lacmax. Nossos resultados sugerem que a manipulação no tempo de pausa em treinamentos intervalados de alta intensidade pode influenciar na magnitude das adaptações ao treinamento Abstract: The aim of this study was to observe the adaptations promoted by the interval training with different rest intervals. Twenty individuals physically active and physical education students were divided into two groups (G1 and G2) and underwent into 14 interval training sessions. Training protocol consisted of sprints of 40 seconds at maximum intensity, with 2 minutes of rest interval for G1 and 5 minutes for G2. The sprints volume was gradually increased throughout the sessions as follow: 4 sprints from 1ª to 3ª, 6 from 4ª to 6ª, and 8 from 7ª to 14ª session. We have evaluated the performance in the 40 seconds test (40s), the velocities of the ventilatory threshold (VLV) and respiratory compensation point (VPCR), and of maximal oxygen consumption (vVO2max.), the maximum oxygen consumption itself (VO2max), body composition (CC), hematological markers, and the kinetics of lactate removal in the 40s (CRL). CC, CRL, and blood samples were accessed one week before the beginning training (Pre), and one week after the end of the program (7D). The vLV, vPCR, vVO2máx, o VO2máx, and 40s were also accessed 14 days after the completion of the training program (14D). Our main findings were: significant changes in 40s performance were observed at 7D and 14D for both groups, however the magnitude of the increase for the G2 at 14D was significantly higher than the G1; No significant changes were observed in red and white cells number; three subjects in G1 increased significantly the vLV at 7D, however four do not present changes for this variable, and one decreased; five subjects in G2 increased significantly the vLV at 7D, however three did not present changes for this variable, and one decreased; four subjects in G1 increased significantly the vPCR at 7D, one decreased and three did not presented any significant change; six subjects in G2 increased significantly the vPCR at 7D, but two did not present any significant change and one decreased; only one subject of G1 increased the vVO2max, meanwhile in G2 three subjects increased significantly and six remained at 7D; taking into consideration the typical error for the vLV protocol (ET=0,62km/h), vPCR (ET=0,35km/h) and vVO2max(ET=0,43km/h), we observed that the number of subjects with significant increases at 14D was greater for a all variables analyzed, suggesting a supercompensation effect of the high intensity interval training after two weeks of rest; No significant changes were observed in Tmax for G1 and G2, with no significant changes were observed for Lacmax in both groups. Our results suggest that rest interval manipulations during high intensity can influence the magnitude of training adaptations Doutorado Biodinâmica do Movimento Humano Doutor em Educação Física

El projecte desenvolupat neix de la necessitat de voler crear un eina capaç de recopilar informació acadèmica i professional d'un usuari, amb un perfil més tècnic, per poder acabar generant un currículum vitae o un porfoli online. Una de les funcionalitats principals de l'eina és la capacitat de sincronització amb fonts de dades de tercers, APIs. Aquestes APIs ens permeten accedir a grans fonts d'informació de manera gratuïta. Principalment s'ha treballat amb les APIs públiques de Github i Linkedin per acabar extraient projectes en els que ha treballat l'usuari, experiència laboral i acadèmica respectivament. El treball s'ha desenvolupat seguint un paradigma incremental, organitzat en iteracions de dues setmanes i organitzant les tasques a desenvolupar mitjançant un tauler kanban. The project developed stems from the need to create a tool capable of collecting academic and professional information from a user, with a more technical profile, in order to end up generating a resume or an online portfolio. One of the main features of the tool is the ability to synchronize with third-party data sources, APIs. These APIs allow us to access large sources of information for free. We have mainly worked with the public APIs of Github and Linkedin to end up extracting projects in which the user has worked, work experience and academic respectively. The work has been developed following an incremental paradigma, organising it in iterations (sprints) of two weeks and organizing the tasks to be performed using a kanban board. El proyecto desarrollado nace de la necesidad de querer crear un herramienta capaz de recopilar información académica y profesional de un usuario, con un perfil más técnico, para poder acabar generando un curriculum vitae o un porfolio online. Una de las funcionalidades de la herramienta es la capacidad de sincronización con fuentes de datos de terceros, APIs. Estas APIs nos permiten acceder a grandes fuentes de información de manera gratuita. Principalmente se ha trabajado con las APIs públicas de Github y Linkedin para terminar extrayendo proyectos en los que ha trabajado el usuario, experiencia laboral y académica respectivamente. El trabajo se ha desarrollado siguiendo un paradigma incremental, organizado en iteraciones de dos semanas y organizando las tareas a desarrollar mediante un tablero kanban.

The purpose of this study was to ascertain the effect of playing three consecutive matches with extra time (ET) on the physical performance of selected Croatian players in their subsequent match, the final of the 2018 Men’s World Cup in Russia. The case study consisted of 4 players on the Croatian national team (16 observations) who had played in all three matches up to 120 min. The consecutive full time matches (90 minutes) and extra time (30 minutes) were compared. The analysis was conducted using data collected by an advanced motion analysis system known as STATS and from interviews with the strength and conditioning coach of the Croatian national team. The recorded variables used were: total distance covered [m], distances covered [m] at intensity ranges of 20–25 km/h and above 25 km/h, and number of sprints performed. All the studied parameters systematically increased in each match up to 90 minutes of play, reached their maximum values in the semi-final and then decreased in the final match. Compared to the first extra time period, in the third extra time period the players covered twice as much distance with an intensity of 20–25 km/h and above 25 km/h, and recorded twice as many sprints. This investigation shows that players in central positions on the pitch are able to maintain or even increase high and very high intensity activity in three consecutive matches with extra time. These data complement the developing body of literature relating to the influence of accumulation of match play with extra time periods on high level players.

Hypoxic training strategies to optimize physiological exercise responses have been extensively investigated, although often with limited performance benefits over the equivalent normoxic training (Roels et al., 2007). Recently, novel methods including intermittent hypoxic resistance training (IHRT) and repeat sprint training in hypoxia (RSH) have begun to receive research attention. Early results indicate that IHRT can augment muscle hypertrophy and strength compared to normoxic training (Nishimura et al., 2010; Manimmanakorn et al., 2013a,b), while RSH improves fatigue resistance, resulting in an increased capacity for repeated maximal efforts (Galvin et al., 2013; Faiss et al., 2013b). Although performing these high-intensity activities in hypoxia appears to provide some benefits for training adaptations, the mechanisms underpinning these responses are not fully understood. The beneficial responses to high-intensity exercise in hypoxia may result from a greater reliance on anaerobic metabolism, suggesting that increased metabolic stress may drive (or at least contribute to) these adaptations (Faiss et al., 2013b; Scott et al., 2015a). Considering the likely importance of metabolic stress on adaptation to IHRT and RSH strategies, the purpose of this paper is to briefly discuss the potential benefits of high-intensity training in hypoxia with reference to the role of anaerobic processes.

[ES] Durante pruebas cíclicas de larga duración ha sido probada que las estrategias para gestionar la fatiga pueden ser un factor determinante. A pesar de ello, este mismo fenómeno no está del todo probado que pueda darse en esfuerzos máximos de corta duración. Es por eso, que el objetivo de este trabajo ha sido analizar si variando el grado de conocimiento de los atletas durante este tipo de pruebas puede darse alguna alteración en su rendimiento. METODO: Siete deportistas varones completaron durante tres diferentes días un mismo protocolo (8 repeticiones máximas de 30 metros con un minuto de recuperación) en el que se varió la información que se les deba. Así, el primer día se les señaló que realizarían 4 repeticiones, pero cuando finalizaron se les indicó que realizarían 4 más (Prueba decepción). El segundo día, no se les informó del número de repeticiones a realizar (Prueba Suspense) y se les mandó parar al realizar la octava. Y por último, el tercer día se les señaló que realizarían 8 repeticiones (Prueba Control). RESULTADOS: Diferencias significativas (p>0.05) se encontraron en los tiempos de las cuatro primeras repeticiones entre la Prueba Suspense y Prueba Decepción. CONCLUSIÓN: Los resultados muestran como en pruebas máximas de corta duración las estrategias de gestión de la fatiga se pueden dar de manera anticipatoria al número de repeticiones a realizar. [EUS] Iraupen luzeko kirol ziklikoetan nekea kudeatzeko erabilitako estrategiak faktore determinante bat izan daitekeela frogatu da. Hala ere, iraupen motzeko esfortzu maximoetan ez dago argi fenomeno bera eman daitekeen. Hori dela eta, lan honen helburu nagusia, mota honetako frogetan parte hartzaileen ezagutza maila aldatuz hauen errendimenduan aldakuntzak eman litezkeen aztertzea izan da. METODOA: Gizonezko zazpi bolondres hartu zuten parte hiru egun ezberdinetan burututako protokoloa berean (8 errepikapen maximoak minutu bateko errekuperazioarekin) non emandako informazioa aldatzen joan zen. Honela, lehenengo egunean 4 errepikapen burutuko zituztela esan zitzaien, hauek bukatzean beste 4 bidaliz (Etsipen Froga). Bigarren egunean ez zitzaien esan zenbat errepikapen burutuko zituzten (Suspense Froga) eta behin zortzigarrena eginda gelditu zitzaien. Azkenik, hirugarren egunean 8 errepikapen burutuko zituztela agindu zitzaien (Kontrol Froga). EMAITZAK: Ezberdintasun adierazgarriak (p>0.05) aurkitu ziren lehenengo lau errepikapenen arteko emaitzetan Etsipen eta Suspense frogen artean. KONKLUSIOA: Emaitzei erreparatuz ondorioztatu daiteke iraupen motzeko esfortzu maximoetan, nekearen gestiorako estrategiak aurre hartzen direla burutuko diren errepikapen kopuruaren arabera [ENG] Pacing strategies have been proposed to occur during continuous cyclical exercise. However, it is not clear if this pacing take place during short maximal exercises. Therefore, the purpose of this study was to examine if changing the knowledge of endpoint in this type of activities, would affect athletes performance. METHOD: Seven male participants completed the same protocol during three days (8 maximal repetitions with a minute of recovery) where the information they received was changed. The first day participants were told to perform 4 repetitions, but after that, they complete 4 more (deception Trial). The second day they did not know the number of total repetition they would do (Unknown Trial) and they were stopped after the eighth. Finally, the third day they were informed to complete 8 repetitions (Control Trial). RESULTS: Significance differences were found (p>0.05) between Deception and Unknown trials during first four repetitions. CONCLUSION: The results propose that pacing strategy can occur during short repeated-sprint efforts in anticipation of the number of sprints that will be completed in the trial.

One of the challenges for sports scientists working in football is to balance the needs for routine fitness testing with daily fatigue and well-being monitoring to best manage the physical preparation of players. In this commentary, the authors examine contemporary issues of fitness testing in football to identify ways of improving the value of routine testing and monitoring. A testing program must be well planned and organized to ensure that the results are useful. Different tests can be employed for younger and older players. A rigorous approach to analysis and interpretation of results is desirable, and database management must address both short- and long-term requirements of players, staff, and programs.

A maioria dos esportes coletivos (ex.: futebol, basquete, handebol) tem como característica a intermitência, flutuando entre breves períodos de esforços máximos ou próximos ao máximo seguidos de períodos e formas de recuperação. Alguns autores têm proposto diversos testes que tem por finalidade mensurar a capacidade desses atletas em realizar esforços repetidos máximos (RSA), a qual estaria diretamente relacionada aos momentos decisivos durante partida. Dessa forma, o presente estudo teve como objetivo descrever os diferentes protocolos de testes para avaliar a RSA em jogadores de futebol, com base em artigos originais e algumas revisões levantadas na base de dados Medline. Diante dos achados, sugerimos a utilização de quatro protocolos, dois envolvendo sprints lineares (AZIZ et al., 2008; REILLY, 2001) e dois utilizando sprints com mudanças de direção (BANGSBO, 2008; IMPELLIZZERI et al., 2008) para avaliação da RSA em jogadores de futebol, gerando importantes parâmetros de desempenho, que permitem ainda a elaboração de programas de treinamento para a melhora dessa capacidade. Recomendamos ainda, a utilização do tempo médio e/ou total como uma medida geral da capacidade de realizar sprints repetidos e as parciais de tempo de cada sprint para identificar possíveis pontos fortes e fraco de cada atleta. The most of team sports (soccer, basketball, handball) is characterized by intermittency, fluctuating between brief periods of maximum effort or near the maximum followed by periods and forms of recovery. Some authors have proposed several tests to measure the ability of these athletes to perform repeated sprints (repeated sprint ability - RSA), which would be directly related to the decisive moments during match. Then, this study aimed to describe the different test protocols to assess RSA in soccer players, based on original articles and reviews selected in some databases (Medline). Therefore, we suggest four protocols, two involving sprints linear (Aziz et al. 2008; Reilly, 2001) and two involving sprints with changes of direction (Bangsbo, 2008; Impellizzeri et al., 2008) to evaluate the RSA in soccer players, generating important performance parameters, which allow to develop training programs to improve that capacity. We also recommend the use of average and/or total time as a general measure of ability to perform repeated sprints and the partial duration of each sprint to identify strengths and weakness of each athlete.

This study aimed to investigate the relationships between high-intensity activities (HIA: speed, acceleration, Metabolic Power) and the outcomes of some technical-tactical skills in professional soccer players (n=610, age 26.8±7.0) during 50 games of the Italian “SERIE A” season 2013-2014. The analysis was carried out through a semi-automatic match analysis video-system. Each technical skill was automatically recognized and the number of events that overcame the threshold values we set as significant for high intensity activities, within 5s before the execution. Shots on goal showed that the HIA might be a discriminant factor in the outcomes (71.1% Success vs 61.5% Not Success, χ2 test, p

Mestrado em Treino de Alto Rendimento Poucos estudos analisaram a composição corporal e as qualidades biomotoras de atletas de alto rendimento masculinos portugueses de hóquei em patins. Objetivo: Descrever marcadores de composição corporal e fisiológicos de atletas de hóquei em patins da seleção nacional de juvenis, juniores e seniores, analisando as diferenças entre escalões. Metodologia: Foram analisados 63 atletas pertencentes aos escalões referidos. Avaliou-se a composição corporal, potência aeróbia (teste de vaivém), potência anaeróbia (teste de sprints), força isométrica (teste de preensão manual, digital e peso morto) e flexibilidade (teste de “senta e alcança modificado” e teste “alcança atrás das costas”). Resultados: Registou-se uma percentagem de massa gorda de 12,5% (juvenis), 13,2% (juniores) e 11,4% (seniores). No teste de vaivém registaram-se 127,8, 127,0 e 123,3 percursos, respetivamente. A força máxima (Fmáx) no peso morto sem patins foi de 1406,4N, 1711,4N e 1878,4N, respetivamente. Juvenis e juniores diferiram na prega subescapular, perímetros da cintura e braquial com flexão, massa isenta de gordura (MIG) e preensão manual. Juvenis e seniores diferiram na prega suprailíaca média, em todos os perímetros, na MIG, peso morto sem patins e preensão digital. Juniores e seniores diferiram nas pregas bicipital, suprailíaca anterior e MIG, na preensão manual e digital e no teste “senta e alcança”. Conclusões: Todos os escalões apresentaram valores similares de %MG e de percursos realizados no teste de vaivém. A Fmáx no peso morto diferiu apenas entre juvenis e juniores.