Acute Responses of Youth Elite Players to a Football Match in Terms of Blood Markers.

The current study verified the acute responses of participants to a football match in terms of blood markers. Sixteen elite U-18 male football players were divided into two groups: experimental (EG, n = 10), who played a friendly football match; and control (CG), who were not exposed to any physical exertion. Intravenous blood samples were collected from both groups at baseline, pre-match, half-time, and post-match. The blood analysis consisted of four groups: immunological (leukocytes, platelets, and cortisol), muscle damage (creatine kinase and lactate dehydrogenase), metabolic (lactate, glucose, erythrocytes, hematocrit, hemoglobin, and urea), and electrolytic (sodium, calcium, and potassium). Edwards' training impulse demonstrated that the first half was more demanding than the second half (p = 0.020). Significant changes between time points and groups were observed for leukocytes (pre-match: 6920 ± 1949; post-match: 13,890 ± 3292; p ≤ 0.05) and cortisol (pre-match: 10.78 ± 3.63; post-match: 19.15 ± 7.40; p ≤ 0.05). CK (pre-match: 516.50 ± 248.38; post-match: 713.70 ± 308.20; p ≤ 0.05) and LDH (pre-match: 348.80 ± 36.49; post-match: 414.80 ± 26.55; p ≤ 0.05) increased significantly across the time points for the EG, with no difference between the groups, however. Raised lactate (pre-match: 1.05 ± 0.32; post-match: 3.24 ± 1.60; p ≤ 0.05) and glucose (pre-match: 72.54 ± 9.76; post-match: 101.42 ± 19.87; p ≤ 0.05) differences between the groups at half-time were also observed. These current findings provide helpful information to better understand football match demands regarding physiological effects.

Relationship Between Body Size and Skeletal Age with Muscle Damage in Young Soccer Players.

This study verified the relationship between body size and skeletal age (SA) with the behavior of blood markers of muscle damage and delayed onset muscle soreness (DOMS) after a soccer match in the U-13 and U-15 categories. The sample consisted of 28 soccer players in the U-13 and 16 in the U-15 categories. Creatine kinase (CK), lactate dehydrogenase (LDH), and DOMS were evaluated up to 72 h after the match. Muscle damage was elevated at 0 h in U-13, and from 0 h to 24 h in U-15. DOMS increased from 0 h to 72 h in U-13 and from 0 h to 48 h in U-15. Significant associations of SA and fat-free mass (FFM) with muscle damage markers and DOMS were observed only in U-13, specifically at time 0 h, when SA explained 56% of CK and 48% of DOMS and FFM explained 48% of DOMS. We concluded that in the U-13 category, higher SA is significantly associated with muscle damage markers, and increase in FFM is associated with muscle damage markers and DOMS. Furthermore, U-13 players need 24 h to recover pre-match muscle damage markers and more than 72 h to recover DOMS. In contrast, the U-15 category needs 48 h to recover muscle damage markers and 72 h to recover DOMS.

The physical exercise-induced oxidative/inflammatory response in peripheral blood mononuclear cells: Signaling cellular energetic stress situations.

Peripheral blood mononuclear cells (PBMCs) are a variety of specialized immune cells produced in the bone marrow from hematopoietic stem cells (HSCs) that work together to protect our bodies from harmful pathogens. From a metabolic point of view, these cells can serve as sentinel tissue source for distinguishing multiple types of whole-body physiological perturbations. The significant interaction of PBMCs with systemic physiology makes these cells an attractive target for several interventions such as physical exercise. Analyses of oxidative/inflammatory and metabolic markers of PBMCs obtained from unhealthy and healthy humans have been used in monitoring immune response in different exercise conditions. It is already a common consensus that regular practice of physical exercise, that is planned, structured, and repetitive, influences personal health by altering the metabolic state and the immune system. However, the role of distinct metabolic processes responsible for maintaining metabolic balance during physical exercise in PBMCs is not fully understood. Furthermore, a complete dose-response analysis between different exercise protocols and biomarkers capable of predicting physical performance needs to be better elucidated. The absence of published reviews on this topic compromises the understanding of the crosstalk between the metabolic adaptations of PBMCs and exercise-induced changes in the immune system. Given the above, this review highlights the main findings in the literature involving the responses of PBMCs in the inflammatory/oxidative stress induced by physical exercise. The present review also highlights how distinct phenotypes and functional diversity of PBMCs make these cells an accessible alternative for assessing exercise-induced metabolic adaptations.

Panax ginseng Supplementation Increases Muscle Recruitment, Attenuates Perceived Effort, and Accelerates Muscle Force Recovery After an Eccentric-Based Exercise in Athletes.

ABSTRACT: Cristina-Souza, G, Santos-Mariano, AC, Lima-Silva, AE, Costa, PL, Domingos, PR, Silva, SF, Abreu, WC, De-Oliveira, FR, and Osiecki, R. Panax Ginseng supplementation increases muscle recruitment, attenuates perceived effort, and accelerates muscle force recovery after an eccentric-based exercise in athletes. J Strength Cond Res 36(4): 991-997, 2022-The effect of Panax ginseng during and after an eccentric-based exercise is underexplored. In this study, we investigated the effect of Panax ginseng on muscle force and muscle excitation during an eccentric-based exercise and on subsequent muscle damage and delayed-onset muscle soreness (DOMS). Using a randomized, double-blind, crossover design, 10 male track and field athletes consumed Panax ginseng or placebo for 8 days. At the fifth day, they performed 4 sets until concentric failure of a half-squat exercise, with eccentric action increased by using an eccentric-inductor device attached to their knees. The rating of perceived exertion (RPE) and vastus lateralis electromyographic (EMG) activity was measured during the half-squat. Plasma lactate dehydrogenase (LDH) and creatine kinase (CK) concentrations, DOMS, and maximal isometric voluntary contractions (MIVCs) with EMG recording were measured at 24, 48, and 72 hours after the half-squat. Panax ginseng attenuated RPE and increased EMG during the sets. The MIVC remained reduced 48 hours after exercise in the placebo but returned to baseline 24 hours after exercise in the Panax ginseng, with values at 24 and 48 hours after exercise significantly higher in the Panax ginseng than in the placebo. The EMG during MIVC was higher in the Panax ginseng than in the placebo over the time points. No significant effect of Panax ginseng on LDH, CK, and DOMS was observed. These findings suggest that Panax ginseng increases muscle excitation and attenuates perceived effort during an eccentric-based exercise as well as accelerates the recovery of muscle force in well-trained athletes.

Could physical, technical, and tactical variables differentiate the top players of the 2018 FIFA World Cup?

Abstract Aim: This study aimed to analyze the difference between tactical, technical, and physical variables in selected and unselected top players of the 2018 FIFA World Cup. Methods: A sample data of 1049 soccer players were collected by the multiple-camera computerised tracking system. Subsequently, data were analyzed and divided into two groups: selected (man of the match and top 10 players of the World Cup) and unselected players (other players). Twenty-six performance variables were used to assess tactical (passing), technical (goals, assist, shots, and fouls), and physical variables (height, distance covered, distance with and without the ball, number of sprints, maximal speed, and intensities zone 1 [low] to 5 [high]). Results: The selected players had more tactical (performed and completed more long, middle, and short pass), technical (goal for, assist, shots, shots on goal, fouls committed on them), and physical variables (covered more distance and distance with the ball, more sprints, greater speed and distance in low intensity [zone 1]). However, they were shorter in height and covered less distance in moderate intensity [zones 2 and 3] when compared to unselected players (p < 0.05). Conclusion: This study suggests that the selected players have more tactical, technical, and physical variables than the unselected players. Our findings could be used as a trustworthy tool (performance variables) to characterize the top players of the World Cup.

Can a genetic profile be related to performance in young talent track and field athletes? A pilot study

Abstract Aim: This study analyzed the influences of ACE and ACTN3 gene variants in sprinters, jumpers, and endurance young athletes of track and field. Methods: 36 school-level competitors of both sex (15 girls and 21 boys; aged 16.4 ± 1.2 years; training experience 4 ± 1.2 years) practitioners of different sport disciplines (i.e., sprint, jump, and endurance athletes) participated in the study. The deoxyribonucleic acid (DNA) was extracted from peripheral blood using a standard protocol. Anthropometric measurements, 30 m sprint, squat jump (SJ), and maximal oxygen uptake (VO2max) tests were measured. Results: Genotype distribution of the ACE and ACTN3 genes did not differ between groups. In ACE DD and ACTN3 RX genotypes, the SJ test was bigger in sprinters and jumpers than in the endurance runners. In contrast, when analyzing the ACE ID genotype, sprinters had higher SJ than endurance athletes. Moreover, in the ACE DD genotype, the sprinters and jumpers' athletes had lower time in 30 m tests compared to endurance runners. However, the ACE ID and ACTN3 RX genotypes was greater aerobic fitness in endurance runners than in jumpers' athletes. Conclusion: Although the genetic profile is not a unique factor for determining athletic performance, the ACE DD and ACTN3 RX genotypes seem to favor athletic performance in power and sprint versus endurance sports. Thus, this study evidenced that assessing genetic variants could be used as an auxiliary way to predict a favorable profile for the identification of young talents of track and field.

Associated Determinants Between Evidence of Burnout, Physical Activity, and Health Behaviors of University Students.

Risk behaviors and signs of burnout are associated with substantial health losses and university dropouts. Physical activity can be an effective approach to reduce these factors. The objective of this study was to analyze aspects related to health behaviors, physical activity, and signs of burnout in university students and their association with physical activity. The probabilistic cluster sample consisted of 3,578 regularly enrolled undergraduate students from UFPR in Curitiba, based on a population sample of 24,032 university students. The students completed the MBI-SS and NCHA II instruments. Descriptive statistics were used to identify demographic indicators and characteristics of the university environment. For the proportion of subjects with respective confidence intervals (CI = 95%), contingency tables involving the chi-square test (χ2) were used. The prevalence of signs of burnout was estimated in punctual proportions accompanied by the respective confidence intervals (CI = 95%). To analyze the associations between the independent variables and signs of burnout, the Hierarchical Logistic Regression was used through an analysis adjusted by the other independent variables involved in the models (CI = 95%). Results showed that the prevalence of individuals who showed signs of burnout was 40.4%. The hierarchical multiple regression model pointed to: female sex (OR = 1.30; 1.11-1.51); age between 20-24 years (OR = 1.51; 1.25-1.83); and 25-29 years (OR = 1.69; 1.27-2.24); being single (OR = 2.67; 1.01-7.10); presenting regular/poor health perception (OR = 1.59; 1.13-2.22), belonging to Human Sciences courses (OR = 1.37; 1.14-1.64); attending 2nd or 3rd year (OR = 1.34; 1.12-1.61); poor academic performance (OR = 5.35; 4.11-6.96); mean (OR = 2.08; 1.78-2.43). We conclude that academics showed a high prevalence of health risk behaviors and correlate and diagnose emotional problems and signs of burnout. Signs of burnout were significantly associated with the practice of physical activity in its three dimensions; however, in the adjusted analysis for demographic indicators, the characteristics of the university environment, and health behaviors, physical activity was not significant for the model.

Predicting Lactate Threshold With Rate of Perceived Exertion in Young Competitive Male Swimmers.

The purpose of this study was to verify the effectiveness of the rate of perceived exertion threshold (RPET) for predicting young competitive swimmers' lactate threshold (LT) during incremental testing. We enrolled 13 male athletes (M age = 16, SD = 0.6 years) in an incremental test protocol consisting of eight repetitions of a 100-meter crawl with 2-minute intervals between each repetition. We collected data for blood lactate concentration ([La]) and Borg scale rate of perceived exertion (RPE) at the end of each repetition. The results obtained were: M RPET = 4.98, SD = 1.12 arbitrary units (A.U.) and M lactate threshold = 4.24, SD = 1.12 mmol.L-1, with [La] and RPE identified by the maximal deviation (Dmax) method without a significant difference (p > 0.05) and large correlations between DmaxLa and DmaxRPE at variables for time (r = 0.64), velocity (r = 0.67) and percentage of personal best time (PB) (r = 0.60). These results suggest that RPET is a good predictor of LT in young competitive swimmers.

Determinant Factors of the Match-Based Internal Load in Elite Soccer Players.

Purpose: To analyze the contribution of physical measures and external load in the match-based internal load of elite soccer players. Methods: Twenty-three elite soccer players (n = 23, age 26.69 ± 3.93 years, body mass 78.04 ± 5.03 kg, height 178.04 ± 5.19 cm, body fat 10.98 ± 1.25%) from a first division soccer team of the Brazilian Championship were evaluated first with anthropometric and physical measures (flexibility and muscle power of lower limbs), and after 24 hrs they were asked to perform an incremental treadmill test (VO2max and ventilatory thresholds). Subsequently, athletes were monitored for 6 weeks during nine official matches of a regional championship. On match days, the external load data (e.g., player load) were collected by triaxial accelerometers with GPS systems and post 30 min after the end of the match the internal load was assessed with the Session Rating of Perceived Exertion method (Session-RPE). Results: Our main findings showed significant contributions of the Player Load (r = .62, p < .001; 42.3%) and Anaerobic Threshold (r = - .199, p = .05, 17%) for the predictive model of Session-RPE. Conclusions: Physical measures and external load have a significant influence on the internal load in elite soccer players. Our findings suggest that sport scientists can use the Session-RPE as a low-cost method for prescribing and monitoring training loads, by the influence of physical measures and external load on the match-based internal load, in order to optimize athletes' performance.

Acute effect of three different warm-up protocols on maximal isokinetic strength in young men / Efecto agudo de tres diferentes protocolos de calentamiento previo en la fuerza isocinética máxima en hombres jóvenes / Efeito agudo de três diferentes protocolos de aquecimento prévio sobre a força isocinética máxima em homens jovens

OBJECTIVE: To investigate the acute effect of three different warm-up protocols on a maximal isokinetic strength test. METHODS: Twenty-two male, recreational athletes involved in regular resistance training were evaluated. Subjects performed a maximal isokinetic strength test of the knee extensors in an isokinetic dynamometer after completing a control session or one of the following warm-up protocols using a randomized design: a general warm-up, stretching warm-up, or specific warm-up. The comparison between treatments was completed through Repeated-Measures Analysis of Variance, followed by a Bonferroni "post hoc" test (p < 0.05). RESULTS: The only difference found was the concentric peak moment following the application of the specific warm-up protocol, which was lower than the control session (12.94%; p < 0.05). No other differences were noted in eccentric peak movement or total work (concentric + eccentric) parameter after application of any the warm-up protocols within control condition (p > 0.05). CONCLUSION: The finding of this investigation showed that none of warm-up protocols applied were able to change the total work of maximal isokinetic strength. Thus, our investigation suggests that the general warm-up, stretching warm-up and specific warm-up have had no adverse or improved effectiveness on acute muscle strength capacity

OBJETIVO: investigar el efecto agudo de tres diferentes protocolos de calentamiento previo en una prueba de fuerza isocinética máxima. MÉTODOS: Fueron evaluados veintidós hombres, atletas recreacionales de entrenamiento resistido. Los individuos realizaron una prueba de fuerza isocinética máxima de los extensores de la rodilla en un dinamómetro isocinético después de una sesión de control o completar uno de los siguientes protocolos de calentamiento previo de forma aleatoria: calentamiento general, calentamiento a través de estiramiento, o calentamiento específico. La comparación, entre los tratamientos, fue realizada a través de un análisis de varianza de medidas repetidas, seguidas por la prueba de "post hoc" de Bonferroni (p <0.05). RESULTADOS: La única diferencia encontrada fue en el pico de torque concéntrico después de la aplicación del calentamiento específico, donde se mostró menor que la sesión control (12.94%; p <0.05). No se observaron otras diferencias en los datos en los parámetros de pico de torque excéntrico o en el trabajo total (concéntrico + excéntrico) después de la aplicación de cualquier protocolo de calentamiento comparando con la sesión de control (p> 0.05). CONCLUSIÓN: Los hallazgos de este estudio mostraron que ninguno de los protocolos de calentamiento utilizados fueron capaces de alterar el trabajo total en la fuerza isocinética máxima. Así, nuestra investigación sugiere que el calentamiento general, calentamiento a través de estiramiento, o calentamiento específico no tuvieron efecto adverso o de mejora en la capacidad de la fuerza muscular máxima de forma aguda

OBJETIVO: investigar o efeito agudo de três diferentes protocolos de aquecimento prévio em um teste força isocinética máxima. MÉTODOS: Foram avaliados vinte e dois homens atletas recreacionais de treinamento resistido. Os indivíduos realizaram um teste força isocinética máxima dos extensores do joelho em um dinamômetro isocinético após uma sessão controle ou completar um dos seguintes protocolos de aquecimento prévio de forma randomizada: aquecimento geral, aquecimento através de alongamento, ou aquecimento específico. A comparação, entre os tratamentos, foi realizada através de uma análise de variância de medidas repetidas, seguidas pelo teste de "post hoc" de Bonferroni (p < 0.05). RESULTADOS: A única diferença encontrada foi no pico de torque concêntrico após a aplicação do aquecimento específico, onde se mostrou menor do que a sessão controle (12.94%; p <0.05). Não foram observadas outras diferenças nos dados nos parâmetros de pico de torque excêntrico ou no trabalho total (concêntrico + excêntrico) após a aplicação de qualquer protocolo de aquecimento comparando com a sessão controle (p> 0.05). CONCLUSÃO: Os achados deste estudo mostraram que nenhum dos protocolos de aquecimento aplicados foram capazes de alterar o trabalho total na força isocinética máxima. Assim, a nossa investigação sugere que o aquecimento geral, aquecimento por alongamento e o aquecimento específico não tiveram efeito adverso ou de melhora na capacidade da força muscular máxima de forma aguda

Pre-planned Vs. Executed Real-Time Pacing Strategies during 3-km Race: Role of Rating Perceived Exertion.

Purpose: The aim of the study was to verify the agreement between preplanned and executed pacing during a 3-km race and determine whether adjustments are mediated by the rating of perceived exertion (RPE). Method: Thirteen young runners (eight males and five females, 17.5 ± 2.1 and 17.0 ± 1.6 years old, respectively) with national and international experience participated in the study. Before the simulated competition, the athletes informed of their preplanned pacing for the distance through a dashboard with the most common pacing profiles and were also asked to complete a questionnaire communicating their preplanned RPE for each lap of race. During 3-km, heart rate (HR), executed RPE and lap time were recorded. Results: Our results showed no significant association between preplanned and executed pacing (p = .631). Moreover, no significant difference between preplanned and executed RPE was found, including the analysis by laps and phases. RPE and HR increased over time during the race (p < .001). Conclusions: The athletes changed from their preplanned pacing, however, their RPE were similar in the preplanned and executed during the 3-km race. These findings indicate that the RPE could be responsible for adjustments in the pacing strategy.

Menstrual cycle alters training strain, monotony, and technical training length in young.

The menstrual cycle (MC) phases carry to several psychophysiological alterations; however, no study has investigated the impact of MC phases on training load or technical training. In the present study, we investigated the effect of the follicular phase (FP), ovulatory phase (OP), and luteal phase (LP) on training load and technical training in young athletes. Twelve female athletes performed regular daily training sessions with the rating of perceived exertion (RPE) and duration being registered every session. Training impulse (TRIMP), monotony and strain were calculated. MC symptoms, RPE, and duration were also measured during technical training, which was carried out on a specific day during each phase. The TRIMP was not affected by MC phases during regular training (p > .05), but training monotony and strain were higher in FP compared to OP (p < .05). During the technical training, MC phases did not affect RPE (p > .05), but the session was longer in both FP and LP, compared to OP (p < .05). MC symptoms were exacerbated in FP compared to both OP and LP (p < .05). These findings suggest that MC disorders were elevated during FP, which indicate that monitoring MC phases might provide important feedbacks for programming training and expected results during competitions.

Limiar anaeróbio em atletas de natação: uma revisão sistemática / Anaerobic threshold in swimming athletes: a systematic review / Umbral anaerobio en atletas de natación: una revisión sistemática

Este artigo objetivou realizar uma revisão sistemática, relatando os métodos utilizados na literatura para a identificação do limiar anaeróbio em nadadores e, além disso, verifi-car a existência de possíveis lacunas que justifiquem a realização de novos estudos. Para isso, buscou-se artigos nas bases de dados eletrônicas Pubmed, Web Of Science, Sci-ELO e Science Direct.O Protocolo de 200 m mostrou-se o mais utilizado, indicando ser o mais adequado para grupos de provas distintas. Porém, constatou-se que a literatura carece de delineamentos adequados para cada estilo de nado, assim como para a especi-alidade de cada atleta. Conclui-se que é possível utilizar diferentes métodos para identi-ficação do limiar anaeróbio e empregá-los na prescrição e controle do treinamento de nadadores.

The objective of this systematic review was to report the methods used in the literature for the identification of the anaerobic threshold in swimmers and to verify the existence of possible gaps that justify the realization of new studies. Articles were searched in the electronic databases of Pubmed, Web Of Science, SciELOeScience Direct.The 200m Protocol is the most used, indicating that it is the most appropriate for different test groups. However, we found that the literature lacks adequate designs for each style of swimming, as well as forthe specialty of each athlete. It is concluded that it is possible to use different methods to identify the anaerobic threshold, providing its use for the prescription and control of training of swimmers.

El objetivo de esta revisión sistemática fue describirlos métodos utilizados en la literatu-ra para la identificación del umbral anaeróbico en nadadores y, verificar la existencia de posibles lagunas que justifiquen la realización de nuevos estudios.Se buscaronartículos en las bases de datos electrónicasPubmed, Web of Science, SciELOyScience Direct. El protocolo de 200 m fue el más utilizado, lo que indica que es el más adecuado para grupos de pruebas distintas.Se constató que la literatura carece de delineamientos para cada estilo de nado, así como para la especialidad de los atletas.Se concluye que es pos-sible utilizar diferentes métodos para identificar el umbral anaeróbico, proporcionando el uso de es te para la prescripción y control del entrenamiento de nadadores.

Physiological, Perceptual, and Affective Responses to Six High-Intensity Interval Training Protocols.

This study examined the extent to which different high-intensity interval training (HIIT) and sprint interval training (SIT) protocols could influence psychophysiological responses in moderately active young men. Fourteen participants completed, in a randomized order, three cycling protocols (SIT: 4 × 30-second all-out sprints; Tabata: 7 × 20 seconds at 170% ⋮O2max; and HIIT: 10 × 60 seconds at 90% HRmax) and three running HIIT protocols (4 × 4 minutes at 90%-95% HRmax, 5 × at v⋮O2max, and 4 × 1,000 meters at a rating of perceived exertion (RPE) of 8, from the OMNI-Walk/Run scale). Oxygen uptake (⋮O2), heart rate, and RPE were recorded during each interval. Affective responses were assessed before and after each trial. The Tabata protocol elicited the highest ⋮O2 and RPE responses, and the least pleasant session-affect among the cycling trials. The v⋮O2max elicited the highest ⋮O2 and RPE responses and the lowest mean session-affect among the running trials. Findings highlight the limited application of SIT and some HIIT protocols to individuals with low fitness levels.

Analysis of psychological variables associated with the burnout syndrome and performance in adult athletes through the athlete burnout questionnaire - abq / Variáveis psicológicas associadas à síndrome de burnout e desempenho em atletas adultos através do athlete burnout questionnaire - abq

ABSTRACT Recently, scholars have been sought to deepen research on a psycho-physiological phenomenon that can lead athletes to quit sports, known in the literature as sport-related burnout. The aim of the present integrative review study was to analyze psychological and performance variables associated with the burnout syndrome in adult athletes. Articles were searched on Pubmed, Web of Science, Scielo, Science Direct, Scopus and Apapsycnet electronic databases, using the following descriptors: burnout, sports and athletes, in both English and Portuguese. From the 15 selected studies, there was predominance of psychological variables associated with burnout over performance aspects. Negative correlations were found between burnout and basic psychological needs, intrinsic motivation and coping strategies. Positive correlations were found between burnout and competitive level, training volume, years of training, perfectionism and overtraining. There were no data on performance increase or decrease related to burnout in adult high-performance athletes, which shows a gap in the literature and encourages new investigations.

RESUMO Recentemente, têm-se procurado aprofundar os estudos sobre o fenômeno psicofisiológico que pode levar atletas ao abandono de sua atividade esportiva conhecido na literatura como burnout no contexto esportivo. O objetivo do presente estudo de revisão integrativa foi analisar as variáveis psicológicas e de desempenho associadas à síndrome de burnout em atletas adultos. Buscaram-se artigos nas bases de dados eletrônicas Pubmed, Web Of Science, Scielo, Science Direct, Scopus, Apapsycnet através dos descritores burnout (burnout), sports (esportes) e athletes (atletas). Constatou-se que houve uma predominância das variáveis psicológicas associadas ao burnout em relação a aspectos de desempenho. Foram encontradas correlações negativas entre necessidades básicas psicológicas, motivação intrínseca, estratégias de coping e burnout, e correlações positivas com nível competitivo, volume de treinamento, tempo de treino, perfeccionismo, overtraining e burnout. Não foram encontrados resultados que inferissem aumento ou queda de desempenho em atletas de alto rendimento relacionados ao burnout, o que sucinta uma lacuna na literatura para novas investigações.

Comparisons of recovery, external and internal load by playing position and match outcome in professional soccer

AIMS: To compare the internal and external load and the recovery by playing position and the match outcome (wins, losses or draws) in professional soccer. METHODS: 23 male professional soccer athletes from a team of the first division of the Brazilian Championship took part into the study (age 26.1 ± 3.8 years old, weight 77.5 ± 5.0 kg, height 177.6 ± 5.1 cm). During the games, athletes were monitored by GPS and the variables of external loads were taken. Additionally, the session rating of perceived exertion (session RPE) and the perceived recovery scale (PRS) were collected 30 minutes and 40h after the end of the matches, respectively. RESULTS: The external load was greater on full-backs and defense midfielders (p<0.05). The full-backs cover higher total distances compared to attackers, and, compared to all the others positions, they have more stimuli > 20 km/h, covering higher distances >20 km/h; these stimuli makes them to perceive less recovered than defenders, defense and attack midfielders (p<0.05). Moreover, the defenders are those who cover lower distances by the minute and the defense midfielders are those who present the lower Peak Velocity (p<0.05). There were no significant differences between GPS variables, internal load and recovery. In addition, it was found a correlation between the external and the internal load (r=0.66; p=0.001). CONCLUSIONS: The GPS variables and the perceived recovery are influenced by the playing position, but not by the match outcome.(AU)

Physiological transition threshold in mountain runners: a systematic review / Limiares de transição fisiológica em corredores de montanhas: uma revisão sistemática

Abstract The identification of physiological transition thresholds (TT) is commonly used for prescribing and evaluating the performance of endurance athletes; however, the methods need further investigation in mountain runner athletes. The aim of the present review was to analyze the different methods used to determine TT in mountain runners. After analyzing 1,176 articles found in different databases, 4 articles that presented a relationship with the theme were selected. Varied proposals were observed, in which the surveys searched for physical and/or cardiorespiratory performance, as well as the effect of acclimatization and training at different altitudes in mountain runners. All studies used spirometry to identify the anaerobic threshold through visual methods and a relative mean intensity in thresholds occurred at 80 - 90% of VO2max. The results of studies analyzed evidenced the limited use of methodologies in the identification of exercises for training evaluation and prescription, as well as the use of effective and low-cost alternative methods to determine these thresholds in mountain runners.

Resumo A identificação dos limiares de transição fisiológica (LT) é comumente utilizada para prescrição e avaliação do desempenho de atletas de endurance, no entanto, os métodos precisam de maiores investigações em atletas corredores de montanhas. O objetivo da presente revisão foi analisar os diferentes métodos utilizados para a determinação dos LT em corredores de montanhas. Após a análise de 1176 artigos encontrados em diferentes bases de dados, foram selecionados 4 artigos que apresentaram relação com o tema. Pode-se observar propostas variadas, nas quais as pesquisas buscaram investigar o desempenho físico e/ou cardiorrespiratório, bem como o efeito da aclimatização e treinamento em diferentes altitudes nos corredores de montanhas. Todos os artigos utilizaram a espirometria para a identificação do limiar anaeróbio, através de métodos visuais e a intensidade média relativa nos limiares ocorreu próxima a valores de 80 - 90% VO2máx. Os resultados dos estudos analisados evidenciam o uso limitado de metodologias na identificação dos LT para a avaliação e prescrição de treinamento, bem como a utilização de métodos alternativos eficazes e de baixo custo para a determinação destes limares em atletas corredores de montanhas.

Pontos de transição da frequência cardíaca na marcha atlética / Transition points of heart rate at race walking / Puntos de transición de la frecuencia cardíaca en la marcha atlética

RESUMO Introdução: A frequência cardíaca fornece informações úteis para os treinamentos de marcha atlética. Objetivo: O objetivo do estudo foi analisar o comportamento da frequência cardíaca (FC) e seus pontos de inflexão (PIFC) e deflexão (PDFC) em teste progressivo de marcha atlética (TPMA) antes e depois de 20 sessões de treinamento. Métodos: Participaram 13 jovens atletas (12,46 ± 1,61 anos, 44,29 ± 10,25 kg, 157,93 ± 12,03 cm, 24,39 ± 7,60 %G). O TPMA foi realizado em uma pista oficial de atletismo, antes e depois do treinamento. Os dados de FC e carga foram plotados a cada minuto para identificação dos PIFC e PDFC. Resultados: A FC apresentou comportamento sigmoide, com identificação dos pontos de transição (PT), sendo no pré-treinamento: a) oito sujeitos PIFC (5,31 km·h-1; 125 bpm) e PDFC (7,63 km·h-1; 169 bpm); b) um sujeito somente PIFC (7,00 km·h-1; 149 bpm); c) um sujeito somente PDFC (8,00 km·h-1; 170 bpm); d) três sujeitos sem detecção de PT e no pós-treinamento: a) em 12 sujeitos PIFC (5,46 km·h-1; 125 bpm) e PDFC (7,75 km·h-1; 168 bpm); b) um sujeito somente PDFC (7,50 km·h-1; 184 bpm). O PIFC foi encontrado em carga significativamente inferior ao PDFC no pré (p < 0,001) e no pós-treinamento (p < 0,001). Quando comparamos o PIFC e o PDFC pré e pós, não encontramos diferença significativa, seja em relação à carga (p = 0,87 e p = 0,61) ou FC (p = 0,60 e p = 0,99). Conclusão: Conclui-se que a FC tem relação curvilínea com a carga, sendo possível detectar os seus pontos de transição em TPMA.

ABSTRACT Introduction: Heart rate provides useful information for race walking training. Objective: The objective of study was to analyze the behavior of heart rate (HR) and inflection points (HRIP) and deflection points (HRDP) in a progressive test of race walking (PTRW) before and after 20 training sessions. Methods: Participants were 13 young athletes (12.46 ± 1.61 years, 44.29 ± 10.25 kg, 157.93 ± 12.03 cm, 24.39 ± 7.60 F%). The PTRW was held at an official athletics track before and after training. The HR data and load were plotted every minute to identify the HRIP and HRDP. Results: The HR showed sigmoid behavior with the identification of transition points (TP), being in the pre-training: a) eight subjects HRIP (5.31 km·h-1; 125 bpm)and HRDP (7.63 km·h-1; 169 bpm); b) one subject only HRIP (7.00 km·h-1; 149 bpm); c) one subject only HRDP (8,00 km·h-1; 170 bpm); d) three subjects had no TP observed, and post-training: a) 12 subjects HRIP (5.46 km·h-1; 125 bpm) and HRDP (7.75 km·h-1; 168 bpm); b) one subject HRDP (7.50 km·h-1; 184 bpm). The HRIP was found to be significantly lower than the HRDP in pre-training (p<0.001) and post-training (p<0.001). When we compared HRIP and HRDP in the pre- and post-training we found no significant difference either in relation to the load (p=0.87 and p=0.61) or HR (p=0.60 and p=0.99). Conclusion: It is concluded that the HR has curvilinear relation with the load, and that it is possible to detect its transition points during PTRW.

RESUMEN Introducción: La frecuencia cardiaca proporciona información útil para los entrenamientos de marcha atlética. Objetivo: El objetivo del estudio fue analizar el comportamiento de la frecuencia cardiaca (FC) y sus puntos de inflexión (PIFC) y de deflexión (PDFC) en prueba progresiva de marcha atlética (PPMA) antes y después de 20 sesiones de entrenamiento. Métodos: Participaron 13 atletas jóvenes (12,46 ± 1,61 años, 44,29 ± 10,25 kg, 157,93 ± 12,03 cm, 24,39 ± 7,60 %G). El PPMA fue realizado en una pista oficial de atletismo antes y después del entrenamiento. Los datos de FC y carga fueron trazados cada minuto para identificación de PIFC y PDFC. Resultados: La FC presentó comportamiento sigmoideo, con identificación de los puntos de transición (PT), siendo en el pre-entrenamiento: a) ocho sujetos PIFC (5,31 km·h-1, 125 lpm) y PDFC (7,63 km·h-1; 169 lpm); b) un sujeto solamente PIFC (7,00 km·h-1; 149 lpm); c) un sujeto solamente PDFC (8,00 km·h-1, 170 lpm); d) tres sujetos sin detección de PT y post-entrenamiento: a) 12 sujetos PIFC (5,46 km·h-1, 125 lpm) y PDFC (7,75 Km·h-1; 168 lpm); b) un sujeto solamente PDFC (7,50 km·h-1, 184 lpm). El PIFC fue encontrado en carga significativamente inferior que el PDFC en el pre (p < 0,001) y en el post-entrenamiento (p < 0,001). Al comparar el PIFC y el PDFC pre y post-entrenamiento, no se encontró ninguna diferencia significativa, sea en relación a la carga (p = 0,87 y p = 0,61) o FC (p = 0,60; p = 0,99). Conclusión: Se concluye que la FC tiene relación curvilínea con la carga, siendo posible detectar sus puntos de transición en PPMA.

Influence of practice time on surfing injuries / Influência do tempo de prática sobre as lesões decorrentes do surf

Abstract Introduction: studying the influence of surfing on the prevalence of injuries may contribute to prevention. Objective: to analyze the influence of time practicing sports and the occurrence of previous surgery on the profile and prevalence of injuries caused by surfing. Methods: Sixty-six Brazilian surfers (26.16 ± 0.73 years old) participated in this study. Anthropometric data, physical activity level, surfing practice time and the prevalence of injuries (type of injury, anatomical region affected, and mechanism of injury) were evaluated. To assess which of the studied variables exerted significant influence on the mean number of injuries, a Poisson log-linear model was adjusted through R software (p < 0.05). Results: most surfers were classified as eutrophic (73%), very active (60.6%), had an average practice time of 10.1 ± 1 years, and were not members of a surfing federation (74%). It was also observed that 90.9% of participants reported injuries caused by surfing and 44.9% affected the lower limbs. The majority of these injuries affected the integumentary system (46.6%). The main mechanism of injury was impact with the board or seabed (40.4%). Furthermore, it was found that surfing federation members presented an average of 58.4% more injuries than non-members (p = 0.007). Surfers who had undergone previous surgeries showed an average number of injuries that was 56.9% higher than other surfers (p = 0.012). In addition, it was found that for each extra year of surfing, the average number of injuries increased by 2.5% (p = 0.0118). Conclusion: the average number of injuries increased with increment in time practicing the sport, previous surgery and membership in a surfing federation.

Resumo Introdução: estudar a influência da prática de surf sobre a prevalência de lesões pode contribuir para sua prevenção. Objetivo: analisar a influência do tempo de prática esportiva e realização de cirurgia prévia sobre o perfil e prevalência das lesões decorrentes do surf. Métodos: Participaram 66 surfistas brasileiros (26,16 ± 0,73 anos). Foram avaliados os dados antropométricos, o nível de atividade física, o tempo de prática de surf e a prevalência de lesões (tipo de lesão, região anatômica acometida e o mecanismo de lesão). Para avaliar quais das variáveis estudadas exerciam influência significativa na média de lesões foi ajustado um modelo log-linear de Poisson por meio do software R (p < 0,05). Resultados: A maior parte dos surfistas foi classificada como eutróficos (73%), muito ativos (60,6%), tempo médio de prática de 10,1 ± 1 anos e não federados (74%). Foi observado que 90,9% dos participantes reportaram lesões decorrentes do surf, sendo que 44,9% destas lesões acometeram os membros inferiores e a maioria atingiu o sistema tegumentar (46,6%). O principal mecanismo de lesão foi o choque com prancha/fundo do mar (40,4%). Ainda, verificou-se que surfistas federados apresentaram média estimada de lesões 58,4% maior que os não federados (p = 0,007). Surfistas submetidos a cirurgias prévias apresentaram média estimada de lesões 56,9% maior que os demais (p = 0,012). Além disso, constatou-se que para cada ano a mais de prática de surf, a média estimada de lesões cresceu 2,5% (p = 0,0118). Conclusão: A média estimada de lesões dos surfistas aumentou com o incremento do tempo de prática, realização de cirurgia pregressa e estar federado.