How does mental fatigue affect soccer performance during small-sided games? A cognitive, tactical and physical approach

Performance of soccer players under acute physical fatigue: An approach based on cognitive, tactical and physical aspects

This study aimed to verify whether peripheral perception, tactical behaviour, and physical performance are influenced by acute physical fatigue in soccer players. The study included 24 trained soccer players (18.6 ± 1.5 years) from two Brazilian clubs. The TSAFT90 test was used to induce acute physical fatigue. The results showed that physical fatigue did not affect peripheral perception (p = 0.360). Regarding tactical behaviour, improved efficiency was observed for the principles of offensive coverage (p = 0.029), width and length with the ball (p = 0.044), and concentration (p = 0.008). On the other hand, a reduction was observed in the number of tactical actions of offensive coverage (p = 0.020) and recovery balance (p = 0.042). Also, improved accuracy in the principles of defensive balance (p = 0.009), recovery balance (p = 0.021) and defensive unity (p = 0.003) occurred under physical fatigue. A reduction in the physical performance outcomes total distance covered (p < 0.001), average speed (p < 0.001), sprints (p = 0.029), number of accelerations (p = 0.008) and decelerations (p = 0.008) were also detected. The internal (p < 0.01) and external (p < 0.01) workload was higher under physical fatigue. Overall, acute physical fatigue did not influence peripheral perception. However, physical performance was reduced under fatigue, the perceived effort increased, and tactical behaviours were affected by decreasing tactical actions performed near the ball, increasing errors in defensive movements in the lateral corridors and the last defensive line, and improving offensive tactical actions performance.

Relative Match Load in Young Professional Soccer Players during Soccer-7 and Soccer-11

The aim of this study was to analyze the differences in internal and external load during Soccer-7 and Soccer-11, comparing positional requirements and neuromuscular fatigue in both modalities. Twenty-four young soccer players were monitored in Soccer-7 and Soccer-11 matches using global positioning systems. Total distance covered (TD), distance covered at high speed (HSR), distance covered at very high speed (VHSR), peak speed, accelerations (Acc) and decelerations (Dec) and rate of perceived exertion (RPE) were recorded differentiating between central backs (CB), midfielders (MF), external players (EX) and forwards (FW). Neuromuscular fatigue were assessed using a jump test. During Soccer-11, players showed significantly higher TD, HSR and VHSR, with low Acc and greater RPE compared with Soccer-7. During Soccer-11, all positions recorded significantly greater TD, distance at HSR and at VHSR than Soccer-7. In terms of playing position, CB, MF and FW achieved significantly higher Peak Speed during Soccer-1, but there was no difference for EX. During Soccer-7 all positions performed significantly higher numbers of Acc. Although the Soccer-7 modality is considered an optimal format for the development of young soccer players, there is a significant difference in match running activity for all playing positions with respect to the Soccer-11 format.

Quantifying Exposure and Intra-Individual Reliability of High-Speed and Sprint Running During Sided-Games Training in Soccer Players: A Systematic Review and Meta-analysis

BACKGROUND

Sided games (i.e., small sided, medium sided, large sided) involve tactical, technical, physical, and psychological elements and are commonly implemented in soccer training. Although soccer sided-games research is plentiful, a meta-analytical synthesis of external load exposure during sided games is lacking.

OBJECTIVE

The objective of this systematic review and meta-analysis was to: (1) synthesize the evidence on high-speed and sprint running exposure induced by sided games in adult soccer players, (2) establish pooled estimates and intra-individual reliability for high-speed and sprint running exposure, and (3) explore the moderating effects of game format and playing constraints.

METHODS

A literature search was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses 2020 guidelines. Four databases (PubMed/MEDLINE, Scopus, SPORTDiscus, Web of Science Core Collection) were systematically searched up to 25 January, 2022. Eligibility criteria were adult soccer players (population); training programs incorporating sided games (intervention); game manipulations including number of players, pitch dimension, and game orientation (comparator); and high-speed, very high-speed, and sprint relative (m[Formula: see text]min^-1) running distances and associated intra-individual reliability (outcome). Eligible study risk of bias was evaluated using RoBANS. Pooled estimates for high-speed and sprint running exposure, and their intra-individual reliability, along with the moderating effect of tracking device running velocity thresholds, pitch dimension (i.e., area per player), and game orientation (i.e. score or possession), were determined via a multi-level mixed-effects meta-analysis. Estimate uncertainty is presented as 95% compatibility intervals (CIs) with the likely range of relative distances in similar future studies determined via 95% prediction intervals.

RESULTS

A total of 104 and 7 studies met our eligibility criteria for the main and reliability analyses, respectively. The range of relative distances covered across small-sided games, medium-sided games, and large-sided games was 14.8 m[Formula: see text]min^-1 (95% CI 12.3-17.4) to 17.2 m[Formula: see text]min^-1 (95% CI 13.5-20.8) for high-speed running, 2.7 m[Formula: see text]min^-1 (95% CI 1.8-3.5) to 3.6 m[Formula: see text]min^-1 (95% CI 2.3-4.8) for very high-speed running, and 0.2 m[Formula: see text]min^-1 (95% CI 0.1-0.4) to 0.7 m[Formula: see text]min^-1 (95% CI 0.5-0.9) for sprinting. Across different game formats, 95% prediction intervals showed future exposure for high-speed, very high-speed running, and sprinting to be 0-46.5 m[Formula: see text]min^-1, 0-14.2 m[Formula: see text]min^-1, and 0-2.6 m[Formula: see text]min^-1, respectively. High-speed, very high-speed running, and sprinting showed poor reliability with a pooled coefficient of variation of 22.8% with distances being moderated by device speed thresholds, pitch dimension, and game orientation.

CONCLUSIONS

This review is the first to provide a detailed synthesis of exposure and intra-individual reliability of high-speed and sprint running during soccer sided games. Our estimates, along with the moderating influence of common programming variables such as velocity thresholds, area per player, and game orientation should be considered for informed planning of small-sided games, medium-sided games, and large-sided games soccer training.

CLINICAL TRIAL REGISTRATION

Open Science Framework available through https://osf.io/a4xr2/ .

The effects of mental fatigue on sport-specific motor performance among team sport athletes: A systematic scoping review

Background

The psychobiological state known as mental fatigue (MF) is by engaging in mentally taxing activities for an extended period, which is typically found in team sports, of the high cognitive demand and unpredictable environment. It increases the perception of effort and influences executive functions, impairing sport-specific performance in athletes. However, the consequences of MF on sport-specific motor performance (SSMP) among athletes in team sports remain unclear.

Objective

This scoping review seeks to find and map research publications that investigate the effect of MF on SSMP in team sports.

Methods

Web of Science, Scopus, and PubMed were searched as the main databases, and CENTRAL, Psychology, and Behavioral Sciences Collection, SPORTDicus obtained from EBSCOhost, as well as gray literature was searched for relevant literature and Google Scholar. Cognitive tasks before the SSMP exam are the focus of the selected literature on mental exhaustion. Only experiments testing mental and non-mental exhaustion were chosen.

Results

Twelve studies fulfill the requirement of selection criteria. SSMP in team sports, including soccer, basketball, cricket, and Australian football mainly is examined as physical and technical performance. More specifically, MF significantly influenced physical performance measured as intermittent endurance and total distance (P < 0.05), while data was inclusive when assess in an ecological setting (e.g., small-sided game) (P > 0.05). Technical performance was mainly measured as ball loss, errors in passing and shooting, interception, and successful tackle and showed a dramatic impairment (P < 0.05). The decline of physical activity is relevant with higher level PRE, while decreased technical performance is related to impaired attention resources shown as visual perceptual.

Conclusion

MF adversely influences SSMP in team sports. The most relevant theory for future study to examine the impacts of MF on team-sport athletes could be the psychological model of exercise and its potential extension on attention resources, rather than the traditional "catastrophe" theory.

PRE-COMPETITION PSYCHOLOGICAL TRAINING IN COLLEGE JUMPING ATHLETES

ABSTRACT Introduction: The psychological state generates great effects on the athletes’ results. Adequate psychological preparation in sports before competitions is fundamental for good performance. The high jump athlete tends to strengthen his physical training during pre-competition practice. However, due to the difficulty of psychological control, emotional variations may occur that significantly limit the technical level of his presentation. Objective: Analyze the psychological training program of college high jumpers on physical fitness and competition performance. Methods: The physical fitness and competition situation of 22 college high jumpers in track and field are discussed. In this paper, 11 cases were randomly selected as the experimental group, and the remaining 11 cases were used as a control group. There was no involvement in directed mental training. The control group received regular exercise training, while the experimental group had regular physical training accompanied by directed psychological training. The fitness and competition results in both groups of athletes before and after the test were evaluated statistically. results: There was a significant difference in presentation performance between the experimental and control groups (P<0.05). Improvements in physical performance were significant in the experimental group. Conclusion: Strengthening psychological training in athletes proved to be a critical factor in improving competition effectiveness. Level of evidence II; Therapeutic studies - investigation of treatment outcomes.

Executive function during exercise is diminished by prolonged cognitive effort in men

The speed and accuracy of decision-making (i.e., executive function (EF) domains) is an integral factor in many sports. At rest, prolonged cognitive load (pCL) impairs reaction time (RT). In contrast, exercise improves RT and EF. We hypothesized that RT and EF during exercise would be diminished by prolonged 'dual tasking' as a consequence of pCL. To test the hypothesis, twenty healthy male participants performed four conditions [resting control (Rest), pCL only (pCL_Rest), exercise only (EX), and pCL + exercise (pCL_EX)] in a randomized-crossover design. Both exercise conditions utilized a 50-min cycling exercise protocol (60% VO₂ peak) and the pCL was achieved via a 50-min colour-word Stroop task (CWST). Compared with Rest, pCL_Rest caused a slowed CWST RT (P < 0.05) and a large SD (i.e., intraindividual variability) of CWST RT (P < 0.01). Similarly, compared with EX, the slowed CWST RT (P < 0.05) and large SD of CWST RT (P < 0.01) were also observed in pCL_EX. Whereas the reverse-Stroop interference was not affected in pCL_Rest (P = 0.46), it was larger (i.e., declined EF) in pCL_EX than EX condition (P < 0.05). These observations provide evidence that the effort of pCL impairs RT and EF even during exercise.

Exploring the impact of the COVID-19 pandemic in Euroleague Basketball

The aim of this study was to understand how training and playing conditions during the COVID-19 pandemic affected the performance of Euroleague Basketball players. Using a non-participant observation analysis, the study compared the seasons before the lockdown (2018-2019 and 2019-2020; pre-pandemic) with the season after restart (2020-2021; pandemic). Paired t-tests and Wilcoxon tests were applied for variables with normal and non-normal distributions, respectively. The results revealed significant changes (p < 0.05) in several offensive and defensive performance-related variables during pandemic times (without attendance): free throw attempts, free throw percentage, turnovers, three-point attempt rate, fouls (small effect sizes, ESs), points, and possessions (trivial ES). The pre-pandemic HA (70%) significantly decreased after the lockdown, with games played with no crowd (∼51%; p = 0.018, large ES). The one-sample t-test showed that the HA after the COVID-19 interruption was not significantly greater than 50%, indicating that the HA did not endure during the pandemic condition. Although significant differences between home and away teams were found for most performance-related variables (excepting turnovers) in both pre-pandemic and pandemic conditions, variations of the relative HA were only significant for free throw attempts (large ES), points (medium ES), and turnovers (medium ES). The results of this study showed that performance variables were affected by the COVID-19 lockdown. Thus, these findings may help coaches, players, and referees to counteract unwanted competitive events and improve their overall performance, regardless of the contextual/situational circumstances encountered.

Physical and Mental Fatigue Reduce Psychomotor Vigilance in Professional Football Players

PURPOSE

Professional football players experience both physical and mental fatigue (MF). The main aims of this randomized crossover study were to investigate the effect of MF on repeated-sprint ability (RSA) and the effects of both physical fatigue and MF on psychomotor vigilance.

METHODS

Seventeen male professional football players performed 10 maximal 20-m shuttle sprints interspaced by incomplete recovery (RSA test). Running speed, heart rate, brain oxygenation, and rating of perceived exertion were monitored during each sprint. The RSA test was preceded by either a 30-minute Stroop task to induce MF or by watching a documentary for 30 minutes (control [CON]) in a randomized counterbalanced order. Participants performed a psychomotor vigilance test at baseline, after the cognitive task (MF or CON), and after the RSA test.

RESULTS

Heart rate and rating of perceived exertion significantly increased, while running speed and brain oxygenation significantly decreased over the repeated sprints (P < .001) with no significant differences between conditions. Response speed during the psychomotor vigilance test significantly declined after the Stroop task but not after CON (P = .001). Response speed during the psychomotor vigilance test declined after the RSA test in both conditions (P < .001) and remained lower in the MF condition compared to CON (P = .012).

CONCLUSIONS

MF does not reduce RSA. However, the results of this study suggest that physical fatigue and MF have negative and cumulative effects on psychomotor vigilance. Therefore, strategies to reduce both physical fatigue and MF should be implemented in professional football players.

Brain Stimulation Over the Motion-Sensitive Midtemporal Area Reduces Deleterious Effects of Mental Fatigue on Perceptual-Cognitive Skills in Basketball Players

The objective of this study was to analyze the effect of anodal transcranial direct current stimulation (a-tDCS) over the motion-sensitive midtemporal area on perceptual-cognitive skills (visuomotor and basketball decision-making skills) in mentally fatigued basketball players. A total of 20 male basketball players were recruited. This was a randomized, double-blinded, and counterbalanced crossover study with two experimental conditions: a-tDCS and Sham. The participants completed the basketball decision-making task and visuomotor skill after performing a 60-min sport-based videogame task with anodal (i.e., a-tDCS) or placebo (Sham) stimulation over the motion-sensitive middle temporal area. Worse response time was observed in visuomotor skill for Sham than a-tDCS postexperiment (p < .05). There was no main condition effect for accuracy of visuomotor skill (p > .05). There was more impairment in accuracy and response time in basketball decision-making skills for the Sham condition than a-tDCS (p < .05). Notably, a-tDCS over the motion-sensitive middle temporal area removed the negative effects of mental fatigue on perceptual-cognitive skills.

Is the Rotatory Knee Stability Immediately Decreased Following a Competitive Soccer Match?

Fatigue induced by soccer playing increases physical efforts, which might alter the transverse knee stability, a known factor that promotes knee injuries, particularly anterior cruciate ligament injury. Thereby, primarily, we aimed to determine whether rotatory knee stability decreases immediately following a competitive soccer match in amateur players. Furthermore, we assessed the role of the preferred and non-preferred limbs to kick a ball in rotatory knee stability and the correlation between performance parameters and rotatory knee stability. We hypothesized that the knee stability decreases immediately after a competitive soccer match in amateur players. Eight healthy amateur soccer players (aged 27.2 ± 4.7 years and with body mass index of 23.8 ± 1.2 kg m−2) were included immediately before and after a competitive soccer match. The rotatory knee stability was assessed in the preferred and non-preferred limbs through the acceleration and jerk of the pivot shift maneuver and by the internal knee rotation of a pivoting landing task. Two-way repeated-measures ANOVA for factors time (before and after the soccer match) and limb (preferred and non-preferred) and multiple comparisons were performed using α = 5%. There was a statistical significance for the main factor time in the acceleration (5.04 vs. 6.90 ms−2, Δ = 1.86 ms−2, p = 0.020, η2 = 0.331) and jerk (18.46 vs. 32.10 ms−2, Δ = 13.64 ms−2, p = 0.004, η2 = 0.456) of the pivot shift maneuver. Rotatory stability decreases following a competitive soccer match in amateur soccer players under fatigue. Both the acceleration and jerk during the pivot shift maneuver is increased without significant internal knee rotation changes during the pivoting landing task.

The effect of physical fatigue on the performance of soccer players: A systematic review

This study aimed to carry out a systematic review to analyze, describe and discuss the effect of physical fatigue on the performance of soccer players. For this systematic review, searches were performed in Pubmed, Web of Science and SPORTDiscus electronic database until October 3, 2020, following the guidelines of PRISMA. A total of 12 articles met the inclusion criteria: i) healthy soccer players from any age group, competitive level or sex; ii) exposure to physical fatigue; iii) pre and post-physical fatigue conditions; iv) players’ cognitive, technical, physical and tactical performances and v) no restrictions regarding the study design. The results section was organized in four main dimensions: cognitive, technical, physical and tactical. Studies on cognitive performance have shown divergent results, varying according to the cognitive task employed and the physical protocol used. Regarding technical performance, negative effects of physical fatigue were found on the technical fundamentals of the pass, dribble and kick. With regard to physical performance, studies have shown a reduction in sprint capacity and distances covered at high velocity. Finally, the only study that analyzed the tactical performance in the field showed an increase in the team’s collective tactical behavior, but did not include analysis of the players’ individual tactical actions. In summary, the results of the analyzed studies show that the effect of physical fatigue on cognitive performance is inconclusive and that technical and physical performance are negatively affected. Regarding tactical performance, there is a lack of information on the topic in the current literature.

Agility and change-of-direction speed are two different abilities also during the execution of repeated trials and in fatigued conditions

Agility and change of direction speed are two different abilities, but no study has investigated if this difference exists also in fatigued conditions, and whether fatigue develops in a different way in a repeated-trial scenario. Fourteen soccer players (age: 17.0 ± 0.4 yrs; height: 176.9 ± 6.5 cm; body mass: 69.2 ± 6.4 kg) competing in a national-level youth league completed in a randomized counter-balanced crossover design a repeated agility protocol (RA) and a repeated change-of-direction one (RCOD), both consisting in performing 20 consecutive repetitions (work:rest ratio 1:5). The 20 repetitions were divided into 4 blocks (each block containing 5 repetitions) for the analysis. Results show that agility and COD are two different abilities both in rest and fatigue conditions: block 1 RA vs 1 RCOD (p < 0.001; ES = 2.02 huge; r = 0.17 poor; r² = 0.03), 2 RA vs 2 RCOD (p < 0.001; ES = 2.3 huge; r = 0.51 fair; r² = 0.26), 3 RA vs 3 RCOD (p < 0.001; ES = 2.38 huge; r = 0.54 fair; r² = 0.29), and 4 RA vs 4 RCOD (p < 0.001; ES = 2.7 huge; r = 0.41 fair; r² = 0.17). However, the fatigue development in both conditions was similar, with a percentage decrement score (S_dec) of 7.5% for RA, and 7.3% for RCOD. Ratings of perceived exertions (RPE) were similar too (7.3 ± 1.7, and 6.6 ± 1.9, for RA and RCOD, respectively). However, a significant fatigue-related performance impairment arose earlier in RA (block 2) than in RCOD (block 3). Total RA and total RCOD times were significantly different (p < 0.001; ES = 2.65 huge; r = 0.41 fair; r² = 0.17), suggesting that they are two different and independent abilities.

The Effect of Acute Caffeine Ingestion on Tactical Performance of Professional Soccer Players

In soccer, physical, tactical, and decision-making processes are highly important facets of successful performance. Caffeine has well established effects for promoting both physical and cognitive performance, but the translation of such benefits specifically for soccer match play is not well established. This study examined the effects of acute caffeine ingestion on tactical performance during small-sided games (SSG) in professional soccer players. Nineteen soccer players (22 ± 4 years) underwent a randomized, counterbalanced, crossover, double-blind placebo-controlled trial. The protocol consisted of 5 bouts of 5-min SSG with 3 players plus a goalkeeper in each team (3 + GK × 3 + GK) with each SSG separated by 1 min rest intervals. Tactical performance was assessed using the system of tactical assessment in soccer (FUT-SAT). Prior to each experimental trial, participants ingested caffeine (5 mg·kg⁻¹) or a placebo 60 min before the protocol. Overall, caffeine ingestion resulted in an increased ball possession time when compared to the placebo. When the offensive and defensive core principles were analyzed, the results were equivocal. Caffeine resulted in positive effects on some tactical decisions during the protocol, but it was deleterious or promoted no observed effect on other of the core tactical principles. Caffeine ingestion resulted in less offensive (during SSG3) and defensive (SSG 2, SSG3, and SSG4) errors. Caffeine ingestion also resulted in higher total offensive success during SSG 1 and SSG2, but it was detrimental during SSG3. Additionally, total defensive success was lower for the caffeine conditions during SSG 2 and SSG5 when compared to the placebo. In conclusion, caffeine influenced aspects of tactical decisions in soccer, resulting in fewer offensive and defensive errors, although it may be deleterious considering other tactical parameters. Future studies may clarify the effects of caffeine ingestion on specific decision-making parameters in soccer.

A Video-Based Tactical Task Does Not Elicit Mental Fatigue and Does Not Impair Soccer Performance in a Subsequent Small-Sided Game

Mental fatigue can impair physical, technical, and tactical performance in sports. Since most previous research used general cognitive tasks to elicit mental fatigue, the aim of this study was to investigate whether a more sport-specific task could induce the effects of mental fatigue and impair the subsequent physical and technical performance in a soccer small-sided game. Ten soccer players performed two small-sided games on two different days in a crossover design. Before each small-sided game, they performed a video-based tactical task (30 min) and a control task (documentary watching, 30 min) in a randomized and counterbalanced order. Mental effort was measured through a visual analog scale after the tactical and control tasks. Subjective ratings of perceived exertion were assessed through the RPE questionnaire after the end of the SSG. Physical performance was assessed during the SSG through GPS technology. Results showed no differences (p > 0.05) in physical performance between the two conditions. None of the technical variables were negatively affected by the video-based tactical condition, with the number of total passes (p = 0.003; ES = 0.72 medium) and successful passes (p = 0.003; ES = 0.82 large) results even improved by the video-based tactical task. The mental effort required by the video-tactical task was significantly higher than the control task (p = 0.002; ES = 2.09 huge). However, overall RPE did not differ between conditions. The video-based tactical task did not elicit mental fatigue and did not impair subsequent physical and technical performance. The higher ecological validity of the task and the higher motivation of the participants might have contributed to the results.

Repeated Interval Loughborough Soccer Passing Tests: An Ecologically Valid Motor Task to Induce Mental Fatigue in Soccer

Most studies investigating mental fatigue (MF) in soccer utilized a computerized Stroop task to induce MF. However, the traditional key-pressing task has been challenged for its lack of ecological validity. The limited relevance to real-life soccer made it difficult to bridge the gap between the research and the applied setting. Therefore, a novel soccer-specific inducing task is in urgent need. This study compared a novel MF-inducing task in soccer with the Stroop task and investigated the impact of induced MF on cognitive and soccer-specific skill performance. A randomized, counterbalanced crossover design was employed. Fifteen well-trained male soccer players randomly participated in three MF-inducing tasks. Two of them were motor tasks consisting of 10 repeated interval Loughborough Soccer Passing Test (10xLSPT or LSPT) in clockwise passing order (10xC-LSPT) with each block starting every 2 min. The two tasks share the same movement pattern, but C-LSPT is considered to have lower cognitive demands. The third was the 20-min Stroop task (Stroop-20). MF was assessed immediately before and after each task by visual analog scale (VAS), the cognitive performance in a 3-min Stroop task, and the skill performance in one LSPT. Subjective MF increased similarly after 10xLSPT and Stroop-20 (+ 25.4 ± 10.3 vs. + 23.4 ± 10.8 AU, p = 0.607). The induced MF by 10xLSPT and Stroop-20 had no impact on cognitive performance and movement time but similarly affected in a significantly negative manner on penalty time (+ 5.9 ± 4.9 vs. + 5.4 ± 4.2 s, p = 0.748) and passing accuracy (-1.4 ± 1.5 vs. -1.0 ± 1.3, p = 0.465). Two motor tasks shared similar intensity, but 10xC-LSPT was inefficient to induce MF. The results showed that the 20-min repeated interval LSPT could induce a similar MF as the Stroop task. The induced MF had detrimental effects on soccer skill performance. The novel motor task is recommended for MF studies in soccer as an inducement task. Practitioners should be cautious about the prolonged cognitive-demanding skill section of the pre-match warm-up to avoid the negative effect of MF on the upcoming match. This motor task pattern could be followed as a supplementary training protocol.

Repeated Use of Transcranial Direct Current Stimulation Over the Dorsolateral Prefrontal Cortex Before Training Changes Visual Search and Improves Decision-Making Response Time in Soccer Athletes

The study aimed to analyze the effect of anodal transcranial direct current stimulation (a-tDCS) over the left dorsolateral prefrontal cortex on soccer athletes’ decision making and visual search behavior. It was a single-blind, randomized, and experimental investigation. The 23 soccer athletes were pair-matched according to decision-making skill and then randomized into two groups: a-tDCS and sham. The decision making (during small-sided game and screen task) and visual search behavior were measured before and after the 8-week intervention. Only the a-tDCS group reduced response time in the decision-making screen task (p < .05). The a-tDCS group showed a higher number of fixations than sham group (p < .05) during the small-sided game. The a-tDCS group showed a lower duration of fixation than sham group (p < .05) during the small-sided game. Our results indicated that using a-tDCS over left dorsolateral prefrontal cortex changed visual search behavior and improved the response time of decision-making skill.

Evaluation of cognitive load in team sports: literature review

In team sports, load management has become one of the most common areas of investigation, given that effective control over load is the key to being able to optimize performance and avoid injuries. Despite the constant evolution and innovation in the latest theories, we can see a clear tendency in load management that focuses on physiological and mechanical aspects and neglects its cognitive character, which generates the variability inherent in the performance of athletes in a changing environment. Indicators of response that inform methods of control over cognitive load can include cognitive, physiological and behavioral indicators. However, limited investigations exist to support the reliability of each indicator regarding cognitive load. For this reason, the objective of this literature review is to present strategies used to manage cognitive load in team sports, as well as the indicators utilized for such a proposition and their relationships in specific contexts.

Topical Review: The Top Five Peripheral Vision Tools in Sport

SIGNIFICANCE

This study summarizes the empirical evidence on the use of peripheral vision for the most-researched peripheral vision tools in sports.

The objective of this review was to explain if and how the tools can be used to investigate peripheral vision usage and how empirical findings with these vision tools might be transferred to sports situations. The data sources used in this study were Scopus, ScienceDirect, and PubMed. We additionally searched the manufacturers' Web pages and used Google Scholar to find full texts that were not available elsewhere. Studies were included if they were published in a peer-reviewed journal, were written in English language, and were conducted in a sports context. From the 10 searched tools, we included the 5 tools with most published studies. In our topical search, we identified 93 studies for the five most-used peripheral vision tools. Surprisingly, none of these studies used eye-tracking methods to control for the use of peripheral vision. Best "passive" control is achieved by tools using (foveal) secondary tasks (Dynavision D2 and Vienna Test System). Best transfer to sports tasks is expected for tools demanding action responses (FitLight, Dynavision D2). Tools are likely to train peripheral monitoring (NeuroTracker), peripheral reaction time (Dynavision D2, Vienna Test System), or peripheral preview (FitLight), whereas one tool did not show any link to peripheral vision processes (Nike SPARQ Vapor Strobe).

Can Rules in Technical-Tactical Decisions Influence on Physical and Mental Load during Soccer Training? A Pilot Study

This study aimed to analyze the effects of rules limitations in pass decisions during soccer tasks on physical and mental load reported by players. Participants were 40 semiprofessional Spanish soccer players (Mage = 22.40, SD = 2.25) from two male teams. Two training sessions with four tasks (same tasks with different score system: two maintaining ball possession games with goalkeepers, and two maintaining ball possession games) in counterbalanced order between teams were completed. To achieve a goal during limitation tasks, a minimum number of players had to participate in the passes before the goal. Internal (perceived effort and heart rate) and external physical load (distances), mental load (validated adaptation of the NASA-TXL) and fatigue (VASfatigue) were quantified. Paired t-test and magnitude-based inference were conducted. The results showed significantly higher mean speeds (p < 0.01), effort perception (p < 0.001), and mental fatigue (very likely positive) during possession games with restrictions. Additionally, performance satisfaction obtained significantly higher values with goalkeepers and pass restrictions (very likely positive). External physical load showed no significant differences between situations. The influence of mental fatigue on internal load and the complexity of the tasks could explain these results. Coaches can use this information to manipulate the training load in ecological conditions.

How do elite female team sport athletes experience mental fatigue? Comparison between international competition, training and preparation camps

Mental fatigue has been shown to negatively influence physical, technical and tactical aspects of sporting performance. However, mental fatigue is not routinely monitored or managed in elite sport and it is not clear whether mental fatigue occurs and/or changes across the varied contextual demands experienced by elite athletes in training, preparation and competition. This study explored self-report measures of mental fatigue across eight training camps and six competition periods (two benchmark tournaments and four international test series) with international netballers (n = 22, 25.9 ± 2.7 years) during the 2018-2019 representative period. Mental fatigue was higher during training camps (p < 0.001; 3.20 [3.12, 3.27]) and preparation camps (p < 0.05; 3.27 [3.19, 3.34]) compared to the competition periods (3.49 [3.44, 3.55]). Significant within-group differences were also identified between individual preparation camps and competition subsets. Higher mental fatigue was reported during the preparation camp for international test series 2 comparative to the preparation camp for benchmark tournament 1 (p = 0.047). For individual competitions; greater mental fatigue was found during the international test series 3 competition in comparison to both the benchmark tournament 1 (p <0.001) and international test series 1 (p = 0.020) competition periods. International representative netballers experience differing levels of mental fatigue across training and preparation camps and competition periods. Practitioners should be aware that athletes report instances of elevated mental fatigue across camps, and competition. Mental fatigue is not limited to competition and thus is recommended to be monitored during periods of training and preparation for competition. HighlightsInternational representative netballers experience differing levels of mental fatigue across camp and competition environments.Mental fatigue was higher during training camps and preparation camps compared to the competition periods.Mental fatigue is not limited to competition so is recommended to be monitored during periods of training and preparation for competition.

Effects of Mental Fatigue in Total Running Distance and Tactical Behavior During Small-Sided Games: A Systematic Review With a Meta-Analysis in Youth and Young Adult's Soccer Players

Background: Mental fatigue can impact physical demands and tactical behavior in sport-related contexts. Small-sided games (SSGs) are often used to develop a specific sport-related context. However, the effects of mental fatigue on physical demands and tactical behaviors during soccer SSGs have not been aggregated for systematical assessment.

Objective: This systematic review (with a meta-analysis) was conducted to compare the effects of mental fatigue vs. control conditions in terms of the total running distance and tactical behavior of soccer players during SSGs.

Methods: The data sources utilized were PubMed, PsycINFO, Scielo, Scopus, SPORTDiscus, and Web of Science. The study eligibility criteria were established based on PICOS: (i) Population: healthy youth and young adult men soccer players with regular training practice and belonging to teams with regular competitions; (ii) Intervention: exposed to mental fatigue-induced protocols only before SSGs; (iii) Comparator: control conditions (passive or active not promoting mental fatigue) before SSGs; (iv) Outcomes: physical demands (total running distance) and tactical behavior (attacking behavior accuracy, pass decision-making accuracy, and space exploration index); (v) Study design: counterbalanced cross-over design; and (vi) only full-text and original articles written in English.

Results: The database search initially identified 111 titles. From those, six articles were eligible for the systematic review and meta-analysis. Results showed no significant effect of fatigue on total running distance (ES = 0.13; p = 0.307) and tactical behavior (ES = 0.56; p = 0.079).

Conclusions: A non-significant effect of mental fatigue on total running distance and tactical behaviors performed by soccer players during SSGs was found in this systematic review.

Internal and External Load Variations in Young Students: Comparisons between Small-Sided Games and Small-Sided Games Combined with Strength Training during Physical Education Classes

The purpose of this study was to compare the effects of internal and external load in soccer small-sided games (SSGs) and a strength program based on CrossFit combined with SSGs for 7 weeks. Fifty-five students participated in this research (age: 9.04 ± 0.19 years) and were randomly assigned to SSGs (n = 27) or strength combined with SSGs (n = 29) group. Two sessions/week were implemented. The results revealed that internal load on SSGs promoted higher levels (p ≤ 0.001; d = 0.35) of light physical activity (PA) (12.24 cpm) compared with strength combined with SSGs (11.46) and % heart rate (%HR) max (p = 0.002; d = 0.48) between SSGs (96.21) regarding strength combined with SSGs (92.09). On external load, significant differences appear in total distance (p ≤ 0.001; d = 0.80) on SSGs (1326 m) compared with strength combined with SSGs (1004 m) and mean velocity (p ≤ 0.001; d = 0.63) in both groups; 2.71 km/h on SSGs and 2.26 km/h on strength combined with SSGs. The SSGs seem to be more appropriate at the beginning of sessions, but as the weeks advance, strength combined with SSGs results in improved internal load compared with SSGs.

Small-sided games: An umbrella review of systematic reviews and meta-analyses

Objective

This umbrella review was conducted to summarize the evidence and qualify the methodological quality of SR and SRMA published on small-sided games in team ball sports.

Methods

A systematic review of Web of Science, PubMed, Cochrane Library, Scopus, and SPORTDiscus databases was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines.

Results

From the 176 studies initially identified, 12 (eight SR and four SRMA) were fully reviewed, and their outcome measures were extracted and analyzed. Methodological quality (with the use of AMSTAR-2) revealed that seven reviews had low quality and five had critically low quality. Two major types of effects of SSGs were observed: (i) short-term acute effects and (ii) long-term adaptations. Four broad dimensions of analysis were found: (i) physiological demands (internal load); (ii) physical demands (external load) or fitness status; (iii) technical actions; and (iv) tactical behavior and collective organization. The psychological domain was reduced to an analysis of enjoyment. The main findings from this umbrella review revealed that SSGs present positive effects in improving aerobic capacity and tactical/technical behaviors, while neuromuscular adaptations present more heterogeneous findings. Factors such as sex, age group, expertise, skill level, or fitness status are also determinants of some acute effects and adaptations.

Conclusion

The current umbrella review allowed to identify that most of the systematic review and meta-analysis conducted in SSGs presents low methodological quality considering the standards. Most of the systematic reviews included in this umbrella revealed that task constraints significantly change the acute responses in exercise, while SSGs are effective in improving aerobic capacity. Future original studies in this topic should improve the methodological quality and improve the experimental study designs for assessing changes in tactical/technical skills.

How Does Cognitive Effort Influence the Tactical Behavior of Soccer Players?

In the present study, we aimed to investigate the association between soccer players' cognitive effort and their tactical behavior. We assessed 52 young male soccer players from a first division Brazilian club, using FUT-SAT to evaluate tactical behavior efficiency and Mobile Eye Tracking-XG software and a video test protocol to measure pupillary behavior and cognitive effort. Following data collection, statistical analyses were performed using the Kolmogorov-Smirnov normality test, and linear regression. We found a high inverse association between cognitive effort and tactical behavior efficiency; players with less cognitive effort during the task displayed higher values of tactical behavior efficiency on the field. We concluded that sustaining less cognitive effort in game situations helped players realize better tactical behavior and enabled better performance.

The association between perceptual-cognitive processes and response time in decision making in young soccer players

In soccer, it is relevant to understand the roles of Systems 1 (intuitive) and 2 (deliberative) in perceptual-cognitive processes and how they influence response time when making decisions. The aim of this study was to analyse how response time in decision making managed by Systems 1 and 2 is associated to the perceptual-cognitive processes of young soccer players. Ninety young soccer players participated. Perceptual-cognitive processes were assessed through visual search strategies, cognitive effort, and verbal reports. Participants wore a mobile-eye tracking system while viewing 11-a-side match play video-based soccer simulations. Response time in decision making was used to create two sub-groups: faster and slower decision-makers. Results indicated that players with faster response time in decision making employed more fixations of shorter duration, displayed less cognitive effort, as well as a greater number of thought processes associated with planning. These results reinforce that there are differences in the way of using the perceptive-cognitive processes from the priority system in the decision-making process. It is concluded that faster decision making, managed by System 1, implies greater ability to employ visual search strategies and to process information, thus enabling increased cognitive efficiency.