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Ocean warming is expected to occur due to anthropogenic climate change bringing a spatial shift of marine communities. Experimental data that characterize the aerobic power budget via an aerobic scope, thermal metabolic scope, or thermal preferences have been proposed as tools that can describe species distribution since they characterize species fitness or performance under different temperatures. This study tested the potential relationship between observed occurrences and different physiological studies in the Americas for 11 commercially important species in Mexico. Projections were also developed for Mexico's exclusive economic zone under different climate warming scenarios. The physiological data were fitted from optimum up to pejus temperatures and projected to sea surface temperatures for present (2003-2014) and Representative Concentration Pathway (RCP) scenarios (RCP 2.6, RCP 4.5, RCP 6.0, and RCP 8.5) for the period 2040-2050 and 2090-2100. For species with wide distributions in the Americas, the number of occurrences reported decreases at higher latitudes related to the decrease in species performance calculated from laboratory experiments. In addition, higher species occurrences are usually reported around optimum temperatures. Overall, the results suggest that pejus temperatures likely restrict latitudinal distribution, at least for widely distributed taxons. Regarding Mexican projections, the results varied widely by species. For example, in the Atlantic Ocean, Octopus maya and Panulirus argus are vulnerable to warming scenarios, while Centropomus undecimalis is not. Interestingly, northern Campeche Bank, the Gulf of California, and Western Baja California may act as thermal refugia for marine species indicating they could be assigned as protected areas to support fisheries throughout the Mexican exclusive economic zone. This research adds to the increasing evidence of the relationship between thermal niche and wild population distribution.

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This study comprises two complementary experiments with athymic Balb/c (Nu/Nu) mice. In experiment 1, the aim was to verify the reproducibility of the peak velocity (VPeak) determined from the incremental test. The second experiment aimed to assess the VPeak sensitivity to prescribe and detect modulations of the physical training in athymic nude mice. Sixteen mice were submitted to two incremental treadmill tests separated by 48-h (Experiment 1). The test consisted of an initial warm-up of 5 minutes. Subsequently, animals initiated the tests at 8 m min-1 with increments of 2 m min-1 every 3 minutes. The VPeak was determined as the highest velocity attained during the protocol. In experiment 2, these animals were randomly allocated to an exercise group (EG) or a control group (CG). The training protocol consisted of 30-min of treadmill running at 70% of the VPeak five times a week for 4 weeks. High indexes of reproducibility were obtained for VPeak (Test = 19.7 ± 3.6 m min-1; Retest = 19.2 ± 3.4 m min-1; p = 0.171; effect size = 0.142; r = 0.90). Animals from the EG had a significant increase of VPeak (Before = 18.4 ± 2.7 m min-1; After = 24.2 ± 6.0 m min-1; p = 0.023). Conversely, a significant decrease was observed for the CG (Before = 21.1 ± 3.9 m min-1; After = 15.9 ± 2.7 m min-1; p = 0.038). The VPeak is a valid parameter for exercise prescription in studies involving athymic nude mice.

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The purpose of this study was to explore the association of the MCT1 gene Glu490Asp polymorphism (rs1049434) with athletic status and performance of endurance athletes. A total of 1,208 Brazilians (318 endurance athletes and 890 non-athletes) and 867 Europeans (315 endurance athletes and 552 non-athletes) were evaluated in a case-control approach. Brazilian participants were classified based on self-declared ethnicity to test whether the polymorphism was different between Caucasians and Afro-descendants. Moreover, 66 Hungarian athletes underwent an incremental test until exhaustion to assess blood lactate levels, while 46 Russian athletes had their maximum oxygen uptake ( V ⋅ O 2 max ) compared between genotypes. In the Brazilian cohort, the major T-allele was more frequent in Caucasian top-level competitors compared to their counterparts of lower competitive level (P = 0.039), and in Afro-descendant athletes compared to non-athletes (P = 0.015). Similarly, the T-allele was more frequent in European athletes (P = 0.029). Meta-analysis of the Brazilian and European cohorts confirmed that the T-allele is over-represented in endurance athletes (OR: 1.48, P = 0.03), especially when Afro-descendant athletes were included in the meta-analysis (OR: 1.58, P = 0.005). Furthermore, carriers of the T/T genotype accumulated less blood lactate in response to intense effort (P < 0.01) and exhibited higher V ⋅ O 2 max (P = 0.04). In conclusion, the Glu490Asp polymorphism was associated with endurance athletic status and performance. Our findings suggest that, although ethnic differences may exist, the presence of the major T-allele (i.e., the Glu-490 allele) favours endurance performance more than the mutant A-allele (i.e., the 490-Asp allele).

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BACKGROUND: Minimum cardiorespiratory fitness (CRF) has been recommended for firefighters due to job requirements. Thus, it is important to identify accurate and readily available methods to assess CRF in this population. Non-exercise CRF estimates (NEx-CRF) have been proposed but this approach requires validation in this population. OBJECTIVE: To evaluate the accuracy of a NEx-CRF, as compared to a field maximum exercise test, among career military firefighters of both genders using a comprehensive agreement analysis. METHODS: We evaluated the accuracy of a NEx-CRF estimate compared to the Cooper 12 min running test among 702 males and 106 female firefighters. RESULTS: Cooper and NEx-CRF tests yielded similar CRF in both genders (differences <1.8±4.7 ml/kg-1.min-1; effect size <0.34). However, NEx-CRF underestimated Cooper-derived CRF among the fittest firefighters. NEx-CRF showed moderate to high sensitivity/specificity to detect fit or unfit firefighters (71.9% among men and 100% among women). Among men, the NEx-CRF method correctly identified most firefighters with less than 11 METs or greater than 13 METs, but showed lower precision to discriminate those with CRF between 11-13 METs. CONCLUSIONS: The NEx-CRF method to estimate firefighters' CRF may be considered as an alternative method when an exercise-based method is not available or may be used to identify those who require more traditional testing (CRF 11-13 METs).

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This study investigated the effects of concurrent training performed either with repetitions to failure or not to failure in muscle power, muscle quality (MQ), peak oxygen uptake (VO2peak), and visceral fat in older men. This is an ancillary analysis of a randomized controlled trial. 36 older men (mean age ± SD; 67.1 ± 5.1 years) were randomized into three groups: one performing repetitions to failure (RFG, n = 13), another performing repetitions not to failure and 50% of the repetitions of the RFG (NFG, n = 12), and third performing repetitions not to failure with equal training volume of the RFG (ENFG, n = 11). The training was performed twice a week for 20 weeks at intensities ranging from 65 to 80% of maximal strength. In each session, the individuals started with strengthening exercises and then performed aerobic exercise (i.e., walking) on a treadmill. The primary endpoint was change from baseline to post-20 wk of absolute and relative muscle power output during squat and countermovement jump, ultrasound measurements for MQ using quadriceps echo intensity, and visceral fat thickness, as well as their VO2peak through a maximal incremental test on a treadmill. All training groups improved similarly and significantly jump height (ranging from 9 to 16%) and all their muscle power outcomes (mean change ranging from 2 to 7%) (P < .001). In addition, all groups significantly decreased visceral fat thickness (ranging from -11 to -21%) (P < .001), and significantly increased VO2peak (ranging from 4 to 8%) (P < .01), with no differences between groups. No changes were observed in the MQ outcomes. Concurrent training performed using repetitions to failure or not to failure promoted similar gains in the muscle power output, aerobic capacity, and visceral fat in healthy older men.

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The aim of this study was to investigate the physiological responses during the time limit at the intensity of the peak velocity of the Carminatti's test (T-CAR). Ten professional futsal players (age, 27.4 ± 5.8 years, body mass, 78.8 ± 8.5 kg, body height, 175.8 ± 6.8 cm, body fat mass, 14.1 ± 2.6%) took part in the study. The players performed three tests, with an interval of at least 48 hours, as follows: the T-CAR to determine the peak velocity and the maximal heart rate; an incremental treadmill protocol to determine the maximal physiological responses; and a time limit running test at the peak velocity reached in the T-CAR. During the last two tests, a portable gas analyzer was used for direct measurement of cardiorespiratory variables. It was shown that the peak velocity was not significantly different from the maximal aerobic speed achieved in the laboratory (p = 0.213). All athletes reached their maximum oxygen uptake during the time limit test. The maximum oxygen uptake achieved during the time limit test was not different from that observed in the laboratory condition (51.1 ± 4.7 vs. 49.6 ± 4.7 ml·kg-1·min-1, respectively, p = 0.100). In addition, Bland and Altman plots evidenced acceptable agreement between them. On average, athletes took ~140 s to achieve maximum oxygen uptake and maintained it for ~180 s. Therefore, the peak velocity intensity can be used as an indicator of maximal aerobic power of futsal athletes and the time limit can be used as a reference for training prescription.

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The aim of this study was to investigate the maximal oxygen uptake (VO2MAX) determined using the incremental phase of the lactate minimum test (LM) on a cycle ergometer. Fifteen trained men were submitted to a graded exercise test (GXT) to evaluate the VO2MAX and LM. The total durations of the GXT and LM were 11.2±1.8 minutes (CI95%:10.2-12.3 minutes) and 25.3±3.2 minutes (CI95%:23.5-27.0), respectively. For the variables measured at exhaustion in both the GXT and LM, the oxygen uptake (54.6 ± 8.1 ml·kg(-1)·min(-1) vs 50.0 ± 7.7 ml·kg(-1)·min(-1)), carbon dioxide production (66.1 ± 7.5 ml·kg(-1)·min(-1) vs 50.4 ± 8.0 ml·kg(-1)·min(-1)), ventilation (153.9 ± 19.0 L·min(-1) vs 129.9 ± 22.9 L·min(-1)), respiratory exchange ratio (1.22 ± 0.10 vs1.01 ± 0.05), maximal power output achieved (331.6 ± 45.8 W vs 242.4 ± 41.0 W), heart rate (183.1 ± 6.9 bpm vs175.9 ± 10.6 bpm) and lactate (10.5 ± 2.3 mmol·L(-1) vs 6.6 ± 2.2 mmol·L(-1)) were statistically lower in the LM (p < 0.05). However, the values of rating of perceived exertion (17.6 ± 2.5 for GXT and 17.2 ± 2.3 for LM) did not differ (ES = 0.12 and CV = 7.8%). There was no good agreement between the values of the VO2MAX from the GXT and VO2PEAK from the LM, as evidenced in the Bland-Altman plot (4.7 ml·kg(-1)·min(-1) and 0.34 L·min(-1) of mean differences, respectively), as well as the high values of the upper and lower limits of agreement. We conclude that the VO2PEAK values obtained in the incremental phase of the LM underestimate the VO2MAX. Key pointsThe VO2MAX is not attained during the incremental phase of the lactate minimum test;The physiological responses at exhaustion during LM are not similar to physiological responses measured during GXT;There is a weak agreement between the peak VO2 measured at exhaustion during LM and the VO2MAX measured during GXT.

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The aims of the present study were to investigate the relationship of aerobic and anaerobic parameters with 400 m performance, and establish which variable better explains long distance performance in swimming. Twenty-two swimmers (19.1±1.5 years, height 173.9±10.0 cm, body mass 71.2±10.2 kg; 76.6±5.3% of 400 m world record) underwent a lactate minimum test to determine lactate minimum speed (LMS) (i.e., aerobic capacity index). Moreover, the swimmers performed a 400 m maximal effort to determine mean speed (S400m), peak oxygen uptake ([Formula: see text]) and total anaerobic contribution (CANA). The CANA was assumed as the sum of alactic and lactic contributions. Physiological parameters of 400 m were determined using the backward extrapolation technique ([Formula: see text] and alactic contributions of CANA) and blood lactate concentration analysis (lactic anaerobic contributions of CANA). The Pearson correlation test and backward multiple regression analysis were used to verify the possible correlations between the physiological indices (predictor factors) and S400m (independent variable) (p < 0.05). Values are presented as mean ± standard deviation. Significant correlations were observed between S400m (1.4±0.1 m·s-1) and LMS (1.3±0.1 m·s-1; r = 0.80), [Formula: see text] (4.5±3.9 L·min-1; r = 0.72) and CANA (4.7±1.5 L·O2; r= 0.44). The best model constructed using multiple regression analysis demonstrated that LMS and [Formula: see text] explained 85% of the 400 m performance variance. When backward multiple regression analysis was performed, CANA lost significance. Thus, the results demonstrated that both aerobic parameters (capacity and power) can be used to predict 400 m swimming performance.

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The objective of this study was to evaluate the genetic and environmental contribution to variation in aerobic power in monozygotic (MZ) and dizygotic (DZ) twins. The sample consisted of 20 MZ individuals (12 females and 8 males) and 16 DZ individuals (12 females and 4 males), aged from 8 to 26 years, residents in Natal, Rio Grande do Norte. The twins were assessed by a multistage fitness test. The rate of heritability found for aerobic power was 77%. Based on the results, the estimated heritability was largely responsible for the differences in aerobic power. This implies that such measures are under strong genetic influence.

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The aim of this study was to examine the relationships among physical fitness of professional Bosnian basketball players (n = 38) and shooting accuracy during one basketball season. A related, secondary aim was to examine relationships between basketball shooting assessments and competitive shooting accuracy during game play. Physical fitness components included: muscular endurance and aerobic endurance, lower and upper-body power, speed, agility, anaerobic capacity and anaerobic power. The specific basketball shooting accuracy was assessed by stationary and dynamic shooting assessments. Competitive shooting accuracy was represented by data collected during one basketball season for each player (free throw, field goal, and three-point %). Results of the regression analyses showed that there were significant positive relationships among shooting assessments and competitive shooting accuracy during game play. The relationship was stronger when the dynamic shooting tests were applied compared to the stationary tests. However, few or weak relationships existed among physical fitness components and competitive shooting accuracy. Only the power tests showed to be good predictors for shooting over longer distances. The findings support the inclusion of the dynamic basketball shooting accuracy tests in regular basketball assessment procedures as a valuable testing instrument.

"A relação entre aptidão física e precisão de arremesso dos jogadores profissionais de basquetebol." O objetivo do presente estudo foi identificar a relação entre a condição física de basquetebolistas profissionais bósnios (n=38) na precisão de arremesso no decorrer de uma temporada competitiva. Adicionalmente, pretendeu-se verificar a relação entre a avaliação específica e a precisão de arremessos durante os jogos. As variáveis de condição física foram as seguintes: resistência de força, resistência aeróbia, potência dos membros inferiores e superiores, velocidade, agilidade, capacidade e potência anaeróbia. A avaliação específica do arremesso foi testada através da utilização de arremessos estáticos e dinâmicos. A precisão dos arremessos durante os jogos foi realizada no decorrer da temporada competitiva mediante análise das seguintes variáveis: lance-livre, arremessos de quadra, e percentagem de arremessos de três pontos. As análises de regressão indicaram a existência de uma relação positiva entre as avaliações específicas dos arremessos e a precisão durante os jogos, a qual foi mais forte nas situações de arremessos dinâmicos comparados aos estáticos. Contudo, as relações existentes entre as variáveis de condição física e a precisão de arremesso durante os jogos foram menores e pouco significativas. Apenas os testes de potência mostraram ser bons preditores para os arremessos efetuados a longas distâncias. Os resultados obtidos apoiam a inclusão de testes de avaliação da precisão de arremessosrealizados de forma dinâmica em procedimentos regulares de avaliação no basquetebol, constituindo-se como instrumentos valiosos para ocontrole do rendimento.

"La relación entre la aptitud física y precisión de tiro de los jugadores profesionales de baloncesto." El objetivo de este estudio fue examinar la relación entre la condición física de los jugadores profesionales de baloncesto de Bosnia (n=38) y la precisión de tiro durante una temporada de baloncesto. Paralelamente, el objetivo secundario fue examinar las relaciones entre las evaluaciones de lanzamiento de baloncesto y la precisión de tiro durante el partido. Los componentes de la aptitud física incluían: la resistencia muscular y la resistencia aeróbica, la potencia de los miembros inferiores y superiores del cuerpo, la velocidad, la agilidad, la capacidad anaeróbica y la potencia anaeróbica. La precisión específica de tiro de baloncesto se evaluó mediante lanzamiento estático y evaluaciones de tiro en movimiento. La precisión de tiro en competición estuvo representada por los datos recogidos durante una temporada de baloncesto para cada jugador (tiro libre, tiro de campo y triple %). Posteriores análisis de los resultados mostraron que había una significativa relación positiva entre las evaluaciones de tiro y la precisión de tiro durante el partido. La relación era más fuerte cuando las pruebas de tiro en movimiento se compararon con las pruebas de tiro estático. Sin embargo, existían pocas o débiles relaciones entre los componentes de la aptitud física y la precisión de tiro en competición. Sólo las pruebas de potencia mostraron ser buenas predictoras para lanzamientos de mayor distancia. Los resultados apoyan la inclusión de los entrenamientos de precisión de tiro en movimiento en los procedimientos habituales de evaluación de baloncesto, como un valioso instrumento de prueba.

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BACKGROUND: Wrestling was an important part of the ancient Olympic Games and is still one of the most popular events of the modern Olympic Games. Studies indicate that general physiologic profile of successful wrestlers is high anaerobic power and capacity, muscular strength, above average aerobic power, exceptional flexibility, fat free mass, and a mesomorphic somatotype. OBJECTIVES: The objective of the present study was to evaluate anthropometric characteristics and physical performance of elite male wrestlers. PATIENTS AND METHODS: The Colombian Wrestling Team was evaluated while in preparation for the Olympic Games (n = 21; age, 27.9 ± 6.7 years). Athletes were tested on anthropometric and fitness parameters: body composition, somatotype distribution according to Heath-Carter, aerobic capacity, vertical jump, and anaerobic power. RESULTS: The evaluations showed a mean body fat percentage of 13.6% ± 3.0% (95% CI, 12.2%-15%), muscle mass of 46.4% ± 2.2% (95% CI, 45.4%-47.4%), Ponderal index of 41.0 ± 1.8 (95% CI, 40.2-41.8), body adiposity index (BAI) 25.1 ± 3.6 (95% CI, 23.5-26.8), and somatotype distribution mesomorphic-ectomorph (5.3-1.6-3.8). Mean aerobic capacity was 45.9 ± 6.6 mL/kg/min (95% CI, 42.8-48.9), vertical jump was 36.4 ± 6.6 cm (95% CI, 11.8-16.6), and anaerobic power was 92.6 ± 19.5 kg/s (95% CI, 83.7-101.5). CONCLUSIONS: These results provided a profile of elite wrestlers that could be used as training targets for developing athletes. The results may also provide information for training and tactical planning.

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O treinamento físico é capaz de proporcionar melhoras dos componentes fisiológicos, metabólicos e neuromusculares em indivíduos com LME cervical, dessa forma, o objetivo do estudo foi de analisar a influência do treinamento de rúgbi em cadeira de rodas nos aspectos fisiológicos e na capacidade funcional dos indivíduos com Lesão da Medula Espinhal. Foram avaliados sete atletas de RCR do sexo masculino com LME cervical (média do grupo de 28,57±6,52anos e tempo de lesão de 7±4,96 anos). Os sujeitos realizaram o Teste de Campo de corrida 12 minutos adaptado em dois momentos distintos, o primeiro antes de realizar a prática esportiva e o segundo momento, após intervenções do treinamento do RCR. Foram observadas diferenças significativas entre as médias da amostra referentes aos valores de Consumo Máximo de Oxigênio (VO2max), número de voltas realizadas (Voltas) e distância percorrida (D) (p?0.05), que inicialmente eram de 10,09 ± 6,91 ml(kg.min)-1, 15 ± 4,95voltas e 1151,3 ± 373,4 metros, respectivamente. Enquanto que, os valores obtidos no final do programa foram de 18,23 ± 8,21 ml(kg.min)-1, 21,14 ± 5,92 voltas e 1592,5 ± 446,5 metros. Conclui-se que a prática de forma regular no RCR gera adaptações e melhoras sobre os componentes fisiológicos e neuromusculares em atletas com LME.

Physical training is able to provide improved on physiological, metabolic and neuromuscular components in individuals with cervical SCI. Thus, the aim of this study was to analyze the influence of wheelchair rugby (WR) training on the physiological and functional capacity of individuals with spinal cord injury. A total of seven male athletes with cervical SCI (group average of 28.57 ± 6.52 years old and 7 ± 4.96 years injury time). The athletes performed the 12-minute adapted running Field Test at two different times; the first before practicing the sport and the second time after the WR training interventions. Significant differences were observed among the sample means regarding Maximum Oxygen Consumption (VO2max), number of laps (Laps) performed and distance (D) (p ? 0.05), which initially were 10.09 ± 6.91ml (kg.min) -1, 15 ± 4.95laps and 1151.3 ± 373.4m, respectively. The values obtained at the end of the program were 18.23 ± 8.21 ml(kg.min)-1, 21.14 ± 5.92laps and 1592.5 ± 446.5m. It can be concluded that regular practice in WR generates adaptations and improvements on the physiological and neuromuscular components in athletes with SCI.

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OBJECTIVE: The purpose of this study was to compare aerobic function [anaerobic threshold (%VO2-AT), respiratory compensation point (%VO2-RCP) and peak oxygen uptake (VO2peak)] between physically active patients with HIV/AIDS and matched controls and to examine associations between disease status, poor muscle strength, depression (as estimated by the profile of mood states questionnaire) and the aerobic performance of patients. METHODS: Progressive treadmill test data for %VO2-AT (V-slope method), RCP and (VO2peak) were compared between 39 male patients with HIV/AIDS (age 40.6±1.4 years) and 28 male controls (age 44.4±2.1 years) drawn from the same community and matched for habitual physical activity. Within-patient data were also examined in relation to CD4+ counts (nadir and current data) and peak isokinetic knee torque. RESULTS: AT, RCP and (VO2peak) values were generally similar for patients and controls.Within the patient sample, binary classification suggested that AT, RCP and (VO2peak) values were not associated with either the nadir or current CD4+ count, but treadmill test variables were positively associated with peak isokinetic knee torque. CONCLUSION: The aerobic performance of physically active patients with HIV/AIDS is generally well conserved. Nevertheless, poor muscle strength is observed in some HIV/AIDS patients, which is associated with lower anaerobic power and (VO2peak), suggesting the possibility of enhancing the aerobic performance of patients with weak muscles through appropriate muscle-strengthening activities.

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Os ajustes fisiológicos ao exercício têm sido extensivamente estudados. Apesar do consenso sobre a importância de testes de exercício para a avaliação do consumo máximo de oxigênio (O2máx), diferenças expressivas entre os protocolos utilizados podem comprometer a comparação de dados e sua utilização clínica ou funcional. A presente revisão analisou os principais protocolos correntemente utilizados na avaliação do O2máx, destacando suas vantagens e limitações. Além disso, compararam-se as características de protocolos escalonados em estágios com aquelas de modelos individualizados, conhecidos como protocolos em rampa. Foram revisados 102 estudos publicados entre os anos 1955 e 2009. Os resultados indicaram que, apesar de a maior parte dos estudos apontar vantagens dos protocolos em rampa sobre os mais tradicionais, há uma evidente carência de recomendações sobre diversos aspectos de sua elaboração. São raros os estudos que analisaram a influência de variáveis dos protocolos em rampa sobre os desfechos pretendidos, como o consumo máximo de oxigênio e limiares de transição metabólica. Há dúvidas acerca da melhor maneira de se determinar a capacidade máxima de exercício, velocidade inicial do teste, razão de incremento, interação velocidade/inclinação e tempo de teste. Em suma, os testes em rampa vêm sendo aplicados com base na experiência dos avaliadores, sem que haja realmente um 'protocolo' que norteie a sua montagem. Estudos que possam contribuir para o desenvolvimento de critérios mais formais e precisos para a elaboração de protocolos em rampa, portanto, fazem-se necessários.

The physiological adjustments to exercise have been extensively investigated. Despite the agreement on the importance of cardiopulmonary exercise testing to assess the maximal oxygen uptake capacity (O2max), expressive differences within the available protocols may compromise the comparison between studies as well as their clinical or functional utilization. The present study analyzed the most frequently used exercise testing protocols to assess the O2max highlighting their pros and cons. Furthermore, the characteristics of staggered protocols were compared to those of individualized models, generally referred as ramp protocols. 102 studies published between 1955 and 2009 were revised. The available studies suggest that ramp protocols would produce better results compared to more traditional staggered tests. However, there is clearly a lack of recommendations regarding the application of such individualized protocols. Very few studies investigated the influence of the testing variables on the main expected results, as O2max and metabolic transition thresholds. It is not clear yet which is the best strategy to determine the maximal exercise capacity, the initial speed of the test, increment ratio, interaction between speed and treadmill inclination, and total duration of the protocol. In conclusion, exercise ramp protocols have been elaborated based on the evaluator experience, since precise recommendations that would define a real 'protocol' do not exist. Studies that contribute to the development of formal and precise criteria for exercise testing ramp protocols design are therefore necessary.

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Rugby is a very popular sport around the world and on the rise in Brazil. It is characterized by the existence of two basic tactics positions (forwards and backs), in which athletes have distinguishing functional demands and physical characteristics. Although the international literature presents a number of interesting data about the physiological and anthropometric profile of these athletes, little attention has been spent to Brazilian athletes. This study aimed to verify the performance of 20 amateur rugby players and to compare the aerobic power (VO2max), anaerobic endurance and isokinetic strength in backs (n = 10) and forwards (n = 10). A computerized gas analyzer (CPX-D - MGC) was used to determine VO2 and VCO2. A Wingate test was used to determine the anaerobic endurance. An isokinetic dynamometer (Cybex Norm) was used to measure isokinetic strength. The body composition was evaluated according to five components of ISAK. The data were compared through Student t test for independent samples (p < 0.05). Our results show a significant difference between backs and forwards in the variables VO2max (47.8 &± 4.5 and 38.8 &± 5.5 ml.kg-1.min-1); 2nd ventilatory threshold (38.3 &± 3.0 and 31.6 &± 4.2 ml.kg-1.min-1); average power (7.5 &± 0.6 and 6.3 &± 1.1 W.kg-1); total work (225.7 &± 18.4 and 187.9 &± 31.7 J.kg-1); body weight (78.5 &± 9.5 and 101.6 &± 12.6 kg); fat mass (24.7 &± 3 , 2 and 29.7 &± 4.6 percent) and muscle mass (48.7 &± 4.2 and 44.5 &± 3.4 percent) respectively (p < 0.05). Thus, there are significant differences, related to the tactic position and function, in Rugby athletes. Furthermore our results shows that even at the amateur level athletes, physiological and anthropometric characteristics are similar when compared to professional level players.

O "Rugby" é um esporte bastante popular internacionalmente e em franca ascensão no Brasil. É caracterizado pela existência de duas posições táticas básicas ("forwards" e "backs"), cujos atletas apresentam demandas funcionais e características físicas distintas. Embora a literatura internacional apresente um número interessante de referências acerca do perfil antropométrico e fisiológico destes atletas, pouca atenção tem sido despendida aos atletas brasileiros. Assim, este trabalho teve como objetivo verificar o desempenho de 20 jogadores amadores de "Rugby" submetidos à ergoespirometria, teste de Wingate e Dinamometria isocinética bem como a comparação entre "backs" (n = 10) e "forwards" (n = 10) para verificar possíveis diferenças entre as posições táticas. Para determinação dos valores de VO2 e VCO2 foi utilizado um analisador de gases computadorizado (CPX-D; MedGraphics Cardiorespiratory Diagnostic Systems) para variáveis de força um dinamômetro isocinético Cybex Norm (Lumex & Co., Ronkonkoma, USA) e para comparações de composição corporal foi aplicada a técnica de cinco componentes da ISAK. A comparação entre os dados foi verificada por meio do teste t de Student para amostras independentes, sendo que para todas as variáveis foi adotado um índice de significância de p < 0,05. Os nossos resultados mostram uma diferença significativa entre "backs" e "forwards' nas variáveis VO2max (47,8 ± 4,5 e 38,8 ± 5,5 ml.kg-1.min-1)...

2º limiar ventilatório (38,3 ± 3,0 e 31,6 ± 4,2 ml.kg-1.min-1) - potência média (7,5 ±0,6 e 6,3 ±1,1 W.kg-1) e trabalho total (225,7 ± 18,4 e 187,9 ± 31,7 J.kg-1) - massa corporal (78,5 ± 9,5 e 101,6 ± 12,6 kg) Massa Adiposa (24,7 ± 3,2 e 29,7 ± 4,6%) Massa Muscular (48,7 ± 4,2 e 44,5 ± 3,4%) respectivamente (p < 0,05). Sendo assim, evidenciamos a existência de diferenças significativas em algumas das variáveis medidas entre atletas de "Rugby' conforme sua função no jogo. Essa evidência mostra que mesmo os atletas sendo de nível amador, as características fisiológicas, antropométricas e mecânicas são semelhantes quando comparadas aos jogadores de nível profissional.

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O objetivo deste estudo foi avaliar a aptidão física das crianças de jogadores de futebol ao longo de um macro treinamento. A amostra foi composta por 16 atletas de futebol infantil, com altura média de 1,74 m (DP = 0,07) e peso corporal médio igual a 63 kg (DP = 6). Analisou-se a potência aeróbia (VO2max), velocidade (T30m), força explosiva de salto vertical (SV) em 4 diferentes tempos de macro (P1, P2, P3, P4). dados análise foi utilizada estatística descritiva e ANOVA de uma via com ajuste de Bonferroni. o principal os resultados foram os seguintes: o VO2max = 13% (P1xP3) e -3,8% (P3xP4); T30m = 4,1% (P1xP2), SV = 5,26% (P2xP3); Foi possível observar a consistência dos resultados com a metodologia proposta adotada, embora os resultados foram mostrados abaixo das expectativas.

The aim of this study was to evaluate children's physical fitness of footballers over a macro training. The sample consisted of 16 athletes from children's football, with average height of 1.74 m (SD = 0.07) and average body weight equal to 63 kg (SD = 6). We analyzed the aerobic power (VO2max), speed (T30m), explosive power of vertical jump (SV) in 4 different times of macro (P1, P2, P3, P4). Data analysis was used descriptive statistics and one-way ANOVA with Bonferroni adjustment. The main results were as follows: VO2max = 13% (P1xP3) and -3.8% (P3xP4); T30m = 4.1% (P1xP2), SV = 5.26% (P2xP3); It was possible to observe the consistency of results with the proposed methodology adopted, although the results have been shown below expectations.

Assuntos

RESUMO

Increased heart rate variability (HRV) and high-frequency content of the terminal region of the ventricular activation of signal-averaged ECG (SAECG) have been reported in athletes. The present study investigates HRV and SAECG parameters as predictors of maximal aerobic power (VO2max) in athletes. HRV, SAECG and VO2max were determined in 18 high-performance long-distance (25 ± 6 years; 17 males) runners 24 h after a training session. Clinical visits, ECG and VO2max determination were scheduled for all athletes during thew training period. A group of 18 untrained healthy volunteers matched for age, gender, and body surface area was included as controls. SAECG was acquired in the resting supine position for 15 min and processed to extract average RR interval (Mean-RR) and root mean squared standard deviation (RMSSD) of the difference of two consecutive normal RR intervals. SAECG variables analyzed in the vector magnitude with 40-250 Hz band-pass bi-directional filtering were: total and 40-æV terminal (LAS40) duration of ventricular activation, RMS voltage of total (RMST) and of the 40-ms terminal region of ventricular activation. Linear and multivariate stepwise logistic regressions oriented by inter-group comparisons were adjusted in significant variables in order to predict VO2max, with a P < 0.05 considered to be significant. VO2max correlated significantly (P < 0.05) with RMST (r = 0.77), Mean-RR (r = 0.62), RMSSD (r = 0.47), and LAS40 (r = -0.39). RMST was the independent predictor of VO2max. In athletes, HRV and high-frequency components of the SAECG correlate with VO2max and the high-frequency content of SAECG is an independent predictor of VO2max.

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