ICI - CIDESD-UBI | Documentos por Auto-Depósito
Permanent URI for this collection
Browse
Recent Submissions
- How playing area dimension and number of players constrain football performance during unbalanced ball possession gamesPublication . Nunes, Nuno André; Gonçalves, Bruno; Coutinho, Diogo; Nakamura, Fábio Yuso; Travassos, BrunoThe aim of this investigation was to analyse the external workload, tactical individual actions of passing, and perceived internal load during unbalanced small-sided games. Ball possession formats (4v3, 4v4 and 4v5) were played in three different playing area dimensions (20 × 15m, 25 × 20m and 30 × 25m) by under-23 football players. Data were analysed under opposition-based perspective, by fixing one team (4vX), and by cooperation-based perspective according to teammates (4v2+X) for each playing area condition. GPS monitors were used to collect and compute external workloads (distance covered while walking, running, sprinting, and maximal speed) and tactical individual actions (passing with dominant and non-dominant foot, and maximum passing speed), and Borg Scale CR10 to evaluate rating of perceived exertion (RPE). On both opposition- and cooperation-based perspectives, significant differences were found on external workload variables for all game formats, with smaller areas associated with more distances covered while walking and larger areas with running and sprinting. Likewise, 4v3, 4v4 and 4v2 + 3 revealed significant differences for tactical individual actions, where a larger area was associated with an increase in repetitions. Medium playing area, for both perspectives, was associated with a higher RPE. Overall, larger playing areas with higher number of players involved promoted more high-intensity running, while the same area with fewer number of players fostered tactical individual actions. Smaller areas allowed to reduce game pace, especially in formats with fewer players. Different unbalance scenarios under dissimilar playing area dimensions promote diverse performance outcomes on player’s action capabilities.
- Macro and micro network metrics as indicators of training tasks adjustment to players’ tactical levelPublication . Machado, João Cláudio; Aquino, Rodrigo; Júnior, Alberto Góes; Júnior, João Bosco; Barreira, Daniel; Travassos, Bruno; Ibanez, Sérgio; Scaglia, Alcides JoséWe aimed to investigate if social networks measures can be used as indicators of training tasks' adjustment level to soccer players’ tactical skills. Twenty-four U17 male soccer players (16.89 ± 0.11 years) participated in this study. The System of Tactical Assessment in Football (FUT-SAT) was used to identify players’ tactical level and to organize them into three groups: Higher tactical level (Group 01), Intermediate tactical level (Group 02) and Lower tactical level (Group 03). Then, the players performed three High difficulty Small-Sided and Conditioned Games (HD-SSCG) and three Low difficulty Small-Sided and Conditioned Games (LD-SSCG). Teams’ interaction patterns and players’ prominence were analysed based on macro (Density – D and Clustering coefficient – CC) and micro networks (Indegree, Outdegree, Total links and Eigenvector) measures. We found that Group 01 presented higher D (p = .004 and ES = 1.189) and CC (p =.004 and ES = .785) at HD-SSCG than Group 03, whereas Group 03 presented higher values of D (p = .003 and ES = 1.200) and CC (p = .037 and ES = 1.180) at LD-SSCG than Group 01. When training tasks difficulty were adjusted to players’ tactical level, teams played more collectively and players were more actively engaged in ball circulation. We concluded that macro and micro networks measures can be applied in training context as indicators of training tasks adjustment to players' tactical level.
- The Co-Occurrence of Satisfaction and Frustration of Basic Psychological Needs and Its Relationship with Exercisers’ MotivationPublication . Rodrigues, Filipe; Macedo, Rita; Teixeira, Diogo; Cid, Luis; Travassos, Bruno; Neiva, Henrique; Monteiro, DiogoAlthough the relationship between both need frustration and, particularly, need satisfaction and different motivational regulations for exercise has been widely examined in the literature, little is known about the co-occurrence of both need satisfaction and need frustration in the exercise context. Grounded in self-determination theory, the present study aimed to examine the effects of both need satisfaction and frustration on motivational regulations for exercise, by applying a response surface analysis approach. In total, 477 regular exercisers aged 18–54 years participated in this study. The interaction between needs (high on both need satisfaction and frustration) displayed a positive and significant association with amotivation, integrated regulation, and intrinsic motivation. Considering the direction of the discrepancy (high vs. low levels of need satisfaction and frustration) related to the behavioral regulations, results showed that higher need satisfaction relative to need frustration was associated with more self-determined regulations of motivation. Contrarily, higher need satisfaction relative to need frustration was associated with lower scores on amotivation, external, introjected, and identified regulation. Overall, these findings extend previous literature, suggesting that need satisfaction and frustration are distinct factors that can be experienced simultaneously in individuals during exercise and that different degrees of both needs have different associations with behavioral regulations.
- Floaters as coach’s joker? Effects of the floaters positioning in 3vs3 small-sided games in futsalPublication . Pizarro, David; Práxedes, Alba; Travassos, Bruno; Gonçalves, Bruno; Moreno, AlbertoThe aim of this study was to analyse the effects of floater positioning within futsal Gk+3vs3+Gk SSGs on youth players’ tactical and physical performance. An independent measure approach under four experimental conditions was carried out: Floaters Off (FO), Goal Line Floaters (GLF), Lateral Floaters own court sidelines (LFocsl) and Lateral Floaters full court sidelines (LFfcsl). Thirty male futsal players (U19 age category) participated in the study. Players’ activity was assessed using WIMU PROTM and heart rate (HR) was recorded by HR monitors during the SSGs. Results showed significant differences in the physical variables (ρ ≤ 0.05), not finding such differences in the tactical variables analysed. However, significant differences were observed in relation to the spatial occupation areas. GLF is related to higher distance and speed variables, being the most demanding SSG; in LFocsl, lower HR values were obtained, and FO is linked to the acceleration and deceleration variables, being an indicator of futsal performance. These findings should be considered for the design of futsal training tasks, according to the context (team, players . . .) and time of the week and the season, since they allow the development of the variables described by optimising training time with the ball.
- Could tDCS Be a Potential Performance-Enhancing Tool for Acute Neurocognitive Modulation in eSports? A Perspective ReviewPublication . Machado, Sergio; Travassos, Bruno; Teixeira, Diogo; Rodrigues, Filipe; Cid, Luis; Monteiro, DiogoCompetitive sports involve physical and cognitive skills. In traditional sports, there is a greater dependence on the development and performance of both motor and cognitive skills, unlike electronic sports (eSports), which depend much more on neurocognitive skills for success. However, little is known about neurocognitive functions and effective strategies designed to develop and optimize neurocognitive performance in eSports athletes. One such strategy is transcranial direct current stimulation (tDCS), characterized as a weak electric current applied on the scalp to induce prolonged changes in cortical excitability. Therefore, our objective is to propose anodal (a)-tDCS as a performance-enhancing tool for neurocognitive functions in eSports. In this manuscript, we discussed the neurocognitive processes that underlie exceptionally skilled performances in eSports and how tDCS could be used for acute modulation of these processes in eSports. Based on the results from tDCS studies in healthy people, professional athletes, and video game players, it seems that tDCS is applied over the left dorsolateral prefrontal cortex (DLPFC) as a potential performance-enhancing tool for neurocognition in eSports.
- Match Analysis of Soccer Refereeing Using Spatiotemporal Data: A Case StudyPublication . Gonçalves, Bruno; Coutinho, Diogo; Travassos, Bruno; Brito, João; Figueiredo, PedroThis case study explored how spatiotemporal data can develop key metrics to evaluate and understand elite soccer referees’ performance during one elite soccer match. The dynamic position of players from both teams, the ball and three elite referees allowed to capture the following performance metrics: (i) assistant referees: alignment with the second last defender; (ii) referee: referee diagonal movement—a position density was computed and a principal component analysis was carried to identify the directions of greatest variability; and (iii) referee: assessing the distance from the referee to the ball. All computations were processed when the ball was in-play and separated by 1st and 2nd halves. The first metric showed an alignment lower than 1 m between the assistant referee and the second last defender. The second metric showed that in the 1st half, the referee position ellipsis area was 548 m2, which increased during the 2nd half (671 m2). The third metric showed an increase in the distance from the referee to the ball and >80% of the distance between 5–30 m during the 2nd half. The findings may be used as a starting point to elaborate normative behavior models from the referee’s movement performance in soccer.
- The Portuguese referee performance modelPublication . Mendes, Sérgio; Oliveira, Ema; Monteiro, Diogo; Travassos, BrunoThe concern with the performance of football referees has opened lines of investigation in areas such as technical and physical performance. Theoretical and analytical gaps regarding the causes of their performances in a holistic perspective are scarce. The purpose of this study is to understand how various processes of personal, career development and contextual nature influences the classification of football referees. The literature review on excellence and the performance of the referees allowed to define a model that contemplates three distinct areas: 1) personal experience; 2) sports course; 3) surrounding context. The model to understand the causes of the performance of the Portuguese referees was obtained by comparing the classification of referees for national boards between the periods of 2009-10 and 2018-19 with the relative data to their age, experience as a federated player and referee, region density and proximity to peers of national board. The results show that the performance of the referees is influenced by a set of processes such as individual experience, sporting background and the context. This article opens a new perspective on the referees' training process. Its content may constitute an important insight for the implementation of referee training programs, namely at the base.
- Effects of numerical unbalance constraints on workload and tactical individual actions during ball possession small-sided soccer games across different age groupsPublication . Nunes, Nuno André; Gonçalves, Bruno; Roca, André; Travassos, BrunoThis study aimed to examine the effects of age group (under-11, under-15, and under-23) on the external, internal workloads, and tactical individual actions when playing 4v2, 4v4, and 4v6 ball possession small-sided soccer games. Data were analysed separately under the opponent perspective (4vX) and by the cooperation perspective, according to teammates (4v2+X). For all opponent formats, statistical differences were found for walking, with older age groups covering longer distances. Higher running distances were found in 4v4 game format for U11s, while U23s reported higher RPE scores in 4v4 and 4v6 formats. More passes were performed in 4v2 and 4v4 game formats for U11s and a higher maximum passing speed in 4v6 format for U15s and U23s. In the cooperation perspective, statistical differences were found for all external workload variables: U11s covered more distances while sprinting, whereas U23s walked more, perceiving the task as more intense. Similarly, U11s performed a higher amount of tactical individual actions also in every format. Younger players seem to benefit from a lower level of opposition to mature tactical individual actions, while older players can develop fast ball circulation in numerical inferiority.
- Effects of acute caffeine ingestion on futsal performance in sub-elite playersPublication . López Samanes, Álvaro; Moreno Pérez, Victor; Travassos, Bruno; Del Coso, JuanPurpose To date, no previous investigation has studied the effect of acute caffeine ingestion on futsal performance during futsal-specific testing and during a simulated match. Therefore, the aim of this investigation was to establish the effects of acute caffeine intake on futsal-specific tests and match-play running performance in male futsal players. Methods Sixteen high-performance futsal players participated in a randomized, crossover, placebo-controlled and double-blind experiment. Each player completed two identical trials after ingesting either caffeine (3 mg/kg) or a placebo (cellulose). The trials consisted of a battery of futsal-specific tests (countermovement jump, 20-m sprint test, and a futsal kicking velocity and accuracy test) followed by a simulated futsal match (2 halves of 7.5 min). During the match, players’ running performance was assessed with local positioning system devices. Results In comparison to the placebo, caffeine ingestion increased jump height by 2.8% (p = 0.048; ES = 0.29) and reduced the time to complete the 20-m sprint test by -2.2% (p = 0.044; ES = − 0.54). Additionally, acute caffeine intake improved the distance covered at above 14.4 km/h by 19.6% (p = 0.021; ES = 0.58), the number of body impacts by 8.1% (p = 0.040; ES = 0.27) and the number of accelerations/decelerations by 4.2% (p = 0.044; ES = 0.57) during the simulated futsal match. However, no differences were reported in ball velocity or shooting accuracy in the futsal kicking test. There were no differences in the prevalence of side effects reported in the hours after the ingestion of the treatments. Conclusion Three mg/kg of caffeine enhanced several physical variables associated with futsal such as jump and sprint performance, and improved high-speed running and accelerations/decelerations during a simulated futsal match. Caffeine supplementation with a moderate dose can be considered as an effective ergogenic aid for futsal performance with low prevalence of side effects.
- How Informational Constraints for Decision-Making on Passing, Dribbling and Shooting Change With the Manipulation of Small-Sided Games Changes in FutsalPublication . Pizarro, David; Práxedes, Alba; Travassos, Bruno; Gonçalves, Bruno; Moreno, AlbertoIn this study, we explored how manipulating floaters’ positions in small-sided futsal games (SSGs) promote changes in the informational constraints that support decision-making (DM) for passing, dribbling and shooting tactics. We made changes in four experimental 3 vs 3 small-sided game conditions with 30 male futsal players (U19 age category): (a) Floaters Off (FO), (b) Final Line Floaters (FLF), (c) Lateral Floaters own field sideline (LFofsl) and (d) Lateral Floaters full field sideline (LFffsl). We assessed players’ activity with WIMU PRO™ software during the SSGs, using the Game Performance Evaluation Tool (GPET) to analyze a total of 1,635 decisions. DM for dribbling was generally based on the interpersonal distance between the ball carrier and direct opponent, considering the defensive team length and the offensive team area. Shooting decisions were constrained, by certain attacking-defending teams’ spatial-temporal relations with regard to playing space and team balance as affected by manipulating floaters’ positions. The coaches’ decisions to change the floaters’ positions during SSGs may change informational variables sustaining the dribbling decision, but no changes in SSG variables affected passing DM.