RESUMO
O objetivo do estudo foi comparar a Potência anaeróbia máxima (Pmáx); Potência Anaeróbia Média (Pmed) e índice de fadiga (IF) entre atletas de diferentes posições táticas no futebol. Para isso, 248 atletas profissionais de futebol de campo (25,8±1,72 anos, 77,52±4,90 Kg e 178,48±5,63 cm), pertencentes a 1ª e 2ª divisão do estado do Rio Grande do Sul, avaliados durante o período de 1999-2010, divididos em cinco posições táticas: goleiros (GO) (n=28), laterais (LA) (n=35), zagueiros (ZA) (n=54), meio-campistas (MC) (n=81) e atacantes (AT) (n=50). Os atletas executaram o RAST test para determinar a Pmáx, Pmed e IF. Foi utilizada a ANOVA one way e post hoc de Tukey adotando-se o valor de significância de p<0,05. Diferenças significativas para a Pmáx (p<0,05) dos LA comparadas aos GO, ZA e MC; da Pmed dos LA para os GO, ZA e MC e dos AT e MC em relação aos GO (p<0,05). Na potência relativa de cada sprint, houve manutenção durante o 1º e 2º sprint entre as posições, exceto os MC e durante o 5º e 6º sprint, independente da posição, não houve decréscimo do desempenho de potência. Visto que foram encontradas diferenças significativas de Pmáx e da Pmed, dos LA em relação aos GO, ZA e MC, concluímos que esta evidência confirma que atletas de diferentes posições táticas apresentam variação quanto às características de suas ações.
This study aimed to compare the maximal anaerobic power (Pmáx), mean anaerobic power (Pm) and fatigue index (FI) among soccer players of different tactical positions. For this purpose, 248 professional soccer players (25.8±1.72 years old, 77.52±4.90 kg and 178.48±5.63 cm) from the 1st and 2nd division of the Rio Grande do Sul State, Brazil, participated in this study. They were evaluated between 1999 and 2010 and divided into five positions: goalkeepers (GK) (n=28), external defenders (ED) (n=35), central defenders (CD) (n=54), midfielders (MF) (n=81), and forwards (F) (n=50). The RAST test was performed to evaluate their Pmáx, Pmed, and FI. ANOVA one-way and Tukey's post hoc were used to evaluate the relationship between the variables; significant level was p<0.05. Significant differences (p<0.05) were found for Pmáx of ED compared to GK, CD and MF. Similarly, Pm of ED also presented significant difference when compared to GK, CD and MF, as well as of F and MF compared to GK (p<0.05). In the relative power of each sprint, the athletes maintained the velocity during the 1st and 2nd sprint regardless of their positions, except for MF, and during the 5th and 6th sprint. There was no decrease in power performance for all positions. Since significant differences were found in Pmáx and Pm of ED compared to GK, CD and MF, we conclude that athletes of different tactical positions presented variation regarding the characteristics of their actions.
RESUMO
The intensity of training might be influenced by exercise mode and type of terrain. Thus, the objective of this study was a) to compare the physiological indices determined in the TCAR test carried out on natural grass (NG) and sandy ground (SG), and b) to analyze heart rate (HR) and blood lactate responses during constant exercise on SG and NG. Ten soccer players (15.11 ± 1.1 years, 168 ± 4.0 cm, 60 ± 4.0 kg) were submitted to the TCAR test to determine peak velocity (PV) and the intensity corresponding to 80.4% PV (V80.4) on NG and SG. The second evaluation consisted of two constant load tests (CLT) (80.4% PV on NG and SG) with a duration of 27 min. The paired Student t-test was used to compare the tests carried out on NG and SG. ANOVA (two-way), complemented by the Tukey test, was used to compare lactate concentrations [La] at 9, 18 and 27 min between the two types of terrain. A p value <0.05 was adopted. PV and V80.4 (15.3±1.0 and 12.3±0.6 km/h) were significantly higher on grass than on sand (14.3±1.0 and 11.5±0.4 km/h). Lactate concentration during the CLT [LaV80.4] was significantly higher on sand (4.1±0.9 mmol/L) than on grass (2.8±0.7 mmol/L). In the CLT, no significant difference in mean HR was observed between the two terrains, whereas there was a difference in [La]. In conclusion, the type of terrain interferes with indicators associated with aerobic power and capacity obtained by the TCAR test.
The intensity of training might be influenced by exercise mode and type of terrain. Thus, the objective of this study was a) to compare the physiological indices determined in the TCAR test carried out on natural grass (NG) and sandy ground (SG), and b) to analyze heart rate (HR) and blood lactate responses during constant exercise on SG and NG. Ten soccer players (15.11 ± 1.1 years, 168 ± 4.0 cm, 60 ± 4.0 kg) were submitted to the TCAR test to determine peak velocity (PV) and the intensity corresponding to 80.4% PV (V80.4) on NG and SG. The second evaluation consisted of two constant load tests (CLT) (80.4% PV on NG and SG) with a duration of 27 min. The paired Student t-test was used to compare the tests carried out on NG and SG. ANOVA (two-way), complemented by the Tukey test, was used to compare lactate concentrations [La] at 9, 18 and 27 min between the two types of terrain. A p value <0.05 was adopted. PV and V80.4 (15.3±1.0 and 12.3±0.6 km/h) were significantly higher on grass than on sand (14.3±1.0 and 11.5±0.4 km/h). Lactate concentration during the CLT [LaV80.4] was significantly higher on sand (4.1±0.9 mmol/L) than on grass (2.8±0.7 mmol/L). In the CLT, no significant difference in mean HR was observed between the two terrains, whereas there was a difference in [La]. In conclusion, the type of terrain interferes with indicators associated with aerobic power and capacity obtained by the TCAR test.
RESUMO
O objetivo deste estudo foi determinar o comportamento da freqüência cardíaca (FC) em teste progressivo máximo em esteira rolante. Vinte universitários foram submetidos a um teste progressivo máximo, à velocidade inicial de 5km.h-1 e incrementos de 0,3 km.h-1 a cada minuto. A identificação dos pontos de transição da FC (PTFC) foi realizada através de modelos matemáticos. Os PTFCs foram observados em todos os sujeitos, com identificação de ponto de inflexão da FC nas fases iniciais (n=3) e finais (n=6) da curva, enquanto o ponto de deflexão da FC foi encontrado em todos os indivíduos, com identificações no início (n=6), final (n=3) e isolado (n=11) na curva. Em concordância com a literatura recente, a partir dos resultados obtidos, verificou-se um comportamento curvilinear da FC em relação à intensidade de trabalho, sendo possível observar a existência de PTFCs em fases iniciais e finais da curva, restando a necessidade da verificação do significado fisiológico destes pontos.
The objective of this study was to determine the heart frequency conduct in a treadmill maximum progressive test. Twenty college students were submitted to a maximum progressive test, with initial speed of 5 km.h-1 and increments of 0,3 km.h-1 each minute. The identification of the heart frequency transition points (HRTP) was done through mathematical models. The HRTP were observed in all subjects, with identification of the heart frequency inflection point in the initial (n=3) and final (n=6) periods of the curve, while the heart frequency deflection point was founded in all subjects, with identifications in the beginning (n=6), in the end (n=3), and isolated (n=11) in the curve. In agreement with recent literature, from the results obtained, a curvilinear behavior of heart frequency related to work intensity was found, allowing the observation of HRDP in initial and final periods of the curve, remaining a necessity of the verification of physiological meanings of these points.