The aim of this study was to establish the validity of the anaerobic threshold (AT) determined on the soccer-specific Hoff circuit (ATHoff) to predict the maximal lactate steady-state exercise intensity (MLSSHoff) with the ball. Sixteen soccer players (age: 16.0 ± 0.5 years; body mass: 63.7 ± 9.0 kg; and height: 169.4 ± 5.3 cm) were submitted to 5 progressive efforts (7.0-11.0 km·h) with ball dribbling. Thereafter, 11 players were submitted to 3 efforts of 30 minutes at 100, 105, and 110% of ATHoff. The ATHoff corresponded to the speed relative to 3.5 mmol·L lactate concentration. The speed relative to 4.0 mmol·L was assumed to be ATHoff4.0, and the ATHoffBI was determined through bisegmented adjustment. For comparisons, Student's t-test, intraclass correlation coefficient (ICC), and Bland and Altman analyses were used. For reproducibility, ICC, typical error, and coefficient of variation were used. No significant difference was found between AT test and retest determined using different methods. A positive correlation was observed between ATHoff and ATHoff4.0. The MLSSHoff (10.6 ± 1.3 km·h) was significantly different compared with ATHoff (10.2 ± 1.2 km·h) and ATHoffBI (9.5 ± 0.4 km·h) but did not show any difference from LAnHoff4.0 (10.7 ± 1.4 km·h). The MLSSHoff presented high ICCs with ATHoff and ATHoff4.0 (ICC = 0.94; and ICC = 0.89; p ≤ 0.05, respectively), without significant correlation with ATHoffBI. The results suggest that AT determined on the Hoff circuit is reproducible and capable of predicting MLSS. The ATHoff4.0 was the method that presented a better approximation to MLSS. Therefore, it is possible to assess submaximal physiological variables through a specific circuit performed with the ball in young soccer players.

The assessment of aerobic endurance is important for training prescription in soccer, and is usually measured by straight running without the ball on a track or treadmill. Due to the ball control and technical demands during a specific soccer test, the running speeds are likely to be lower compared to a continuous incremental test. The aim of the present study was to compare the heart rate (HR), rating of perceived exertion (RPE) and speeds corresponding to 2.0 mmol∙L-1, 3.5 mmol∙L-1, lactate threshold (Dmax method) and peak lactate determined in the laboratory and in the Hoff circuit soccer-specific test. Sixteen soccer players (16±1 years) underwent two incremental tests (laboratory and Hoff circuit tests). The speeds were significantly higher in the treadmill test than on the Hoff circuit (2.0 mmol∙L-1: 9.5±1.2 and 8.1±1.0 km∙h-1; 3.5 mmol∙L-1: 12.0±1.2 and 10.2±1.1 km∙h-1; Dmax: 11.4±1.4 and 9.3±0.4 km∙h-1; peak lactate: 14.9±1.6 and 10.9±0.8 km∙h-1). The HR corresponding to 3.5 mmol∙L-1 was significantly higher on the Hoff circuit compared to the laboratory test (187.5±18.0 and 178.2±17.6 bpm, respectively; P <0.001), while the RPE at the last incremental stage was lower on the Hoff circuit (P < 0.01). The speeds during the Hoff specific soccer test and the HR corresponding to 2.0 mmol∙L-1, 3.5 mmol∙L-1 and Dmax/threshold were different compared with the laboratory test. The present study shows that it is possible to assess submaximal endurance related variables specifically in soccer players.

The use of small-sided games (SSG) for soccer training has increased considerably in recent years. Tactical principles can influence the intensity and the movement of soccer players during training. The aim of this study was to evaluate the influence of maintaining possession of the ball on the intensity and the time of motion characteristics of players during training in games. Eleven athletes of the U-20 category of a professional club in São Paulo, Brazil, participated in this study. To check the influence of the tactical principle, we used a game control and an experimental game in three different field dimensions and number of players. The results show that possession of the maintenance rule influences the intensity of the games (p<0.05). However, it is concluded that the rule is fundamental for training through games.

O objetivo do estudo foi investigar a influência da dimensão do campo e do número de jogadores nos aspectos táticos e técnicos em diferentes formatos de jogos. Para tanto, quatorze jogadores de futebol pertencentes à categoria sub-20 participaram de três estruturas de jogos distintas: Gr+3vs3+Gr (27x18 m), Gr+6vs6+Gr (52x32 m) e Gr+10vs10+Gr (105x64 m), em duas condições: Jogo Controle e Jogo de Manutenção. Os jogos foram filmados por quatro câmeras de vídeos digitais. Posteriormente, as sequências de imagens foram analisadas no software Dvideo, que possibilitou obter a posição de todos os jogadores em função do tempo e o registro das ações técnicas ocorridas. Desse modo, foram analisadas as variáveis táticas “Centro de Jogo” e “Densidade Ofensiva” (igualdade numérica, superioridade ofensiva e defensiva), assim como as variáveis técnicas de passe, domínio, condução, finalização, desarme, interceptação e carga técnica. Os resultados mostraram diferenças significativas nos indicadores táticos de participação no centro de jogo (p<0.01), igualdade numérica (p<0.01), superioridade defensiva (p<0.01) e ofensiva(p<0.05). Em relação às ações técnicas, foi possível verificar diferenças significativas no passe (p<0.01), domínio (p<0.01), condução (p<0.01), finalização (p<0.01), desarme (p<0.05), interceptação (p<0.01) e na carga técnica (p<0.01). Concluímos que, a manipulação da dimensão do campo e do número de jogadores influencia a emergência de comportamentos técnico-táticos específicos, o que possibilita treinadores adequarem as estruturas dos jogos para a elaboração de exercícios que estejam de acordo com os seus objetivos pedagógicos.

Introduction: During training in games, it is essential to know how to correctly manipulate the formats of the games (size of field and number of players). Objective: The aim of this study was to evaluate the influence of three different game formats on the kinematic variables of training in soccer players. Methods: For this purpose, eleven U-20 soccer players participated in three games formats, Gr+3vs3+Gr, Gr+6vs6+Gr and Gr+10vs10+Gr in two conditions (experimental and conceptual). Through videogametry, it was possible to determine the range of speeds covered by the players during the games and to correlate with the ventilatory threshold (VT) evaluation individually to establish four different intensity zones (low intensity, moderate intensity, moderate/high intensity or high intensity). Results: It was verified that in the experimental games, when increasing the size of the field there were significant increases in the intensity of the game. In the conceptual games, there were only significant increases of the field Gr+10vs10+Gr for the games Gr+6vs6+Gr and Gr+3vs3+Gr. Conclusion: It is concluded that the format of the games has a significant effect on the movement of players. Level of Evidence III; Case-control study.