Level of play and coach-rated game intelligence are related to performance on design fluency in elite soccer players

Effects of fasting during Ramadan month on soccer-specific technical performance, cognitive function, and perceptions in soccer players

We aimed to examine the effects of Ramadan fasting (RF) and high-intensity short-term maximal performance on elite soccer players' shooting accuracy, executive function (EF), and perceptions. Sixteen Muslim elite players fasting during Ramadan underwent assessments before (BR), during (DR), and after Ramadan (AR). Soccer-specific technical performance was evaluated using the Loughborough Soccer Shooting Test (LSST) before and after a 5-metre shuttle run test (5mSRT), conducted at the same time-of-day (17:00 h). Performance metrics recorded included higher distance (HD), total distance (TD), and fatigue index (FI). RPE after a 5-min warm-up and each repetition of the 5mSRT were obtained, and the mean RPE score was calculated. Trail Making Test (TMT Parts A and B) were used after the warm-up and the 5mSRT. Perceived difficulty (PD) was assessed following the LSST. HD, TD, and FI were not affected by RF (p > 0.05). DR, RPE and accuracy scores in the LSST were significantly lower after the 5mSRT compared to BR (1.29 vs. 1.24 AU; 1.29 vs. 1.24, respectively). In conclusion, RF had no adverse effects on physical performance. However, when combined with high-intensity running sessions, RF may impact accuracy and PD, and these adverse effects seem to have been translated into EF.

The interaction between acute emotional states and executive functions in youth elite soccer players

Introduction

Executive functions (EFs) are relevant for game performance in soccer and have been investigated in previous research. However, emotions are a well-known performance factor in sport competitions, which may affect performance by means of EFs. The diagnostic of EFs has mainly been performed disregarding the potential impact of emotional states. Thus, we aimed to initially analyze interaction between emotional states and EFs in two studies with male youth elite soccer players.

Methods

In the first study, 105 players (Mage = 14.97) completed computerized tasks assessing inhibition, cognitive flexibility and working memory. In the second study, 92 players (Mage = 15.17) performed adapted and validated tests of inhibition (n = 45) or cognitive flexibility (n = 47) in a soccer-specific setting (SoccerBot360). Emotional and affective states were assessed using the German Sport Emotion Questionnaire and self-assessment manikins.

Results

For the computerized tasks, results showed a significant negative correlation between switch costs accuracy and tension, r = 0.28, indicating lower error rates with higher levels of tension. In contrast, in the SoccerBot360 we found significant positive correlations for response time and tension (no-switch: r = 0.38; switch: r = 0.39) representing prolonged response times related to tension. Further, for soccer-specific inhibition, positive emotions were significantly positively correlated with response time (congruent: r = 0.32; incongruent: r = 0.32). Subsequent regression analyses also demonstrate that valence and arousal effectively explain variance in cognitive performance parameters under neutral conditions.

Discussion

Accordingly, the ambiguity of the results suggests high variability in EF performance, affective and emotional states as well as a potentially moderating influence of other variables such as context and task difficulty. Thus, future cognitive diagnostic research should integrate assessments of emotional and affective states as these may contribute to situational fluctuations in EF performance.

Cognition in soccer and futsal: evidence of validity of a 4-instrument protocol to assess executive functioning among women athletes

Evidence suggests that success in sports, especially soccer and futsal are linked to higher levels of executive functioning. Still, the literature does not present a homogeneous set of instruments to measure executive functions, which leads to large variability in results. In this paper, we assembled four already recognised measures to propose a valid 4-instrument protocol to assess executive functions among soccer and futsal athletes. We conducted two studies to validate the proposed protocol. We addressed known-groups validity and latent structure in Study 1 for data collected on 105 female soccer and futsal athletes from elite and lower-division clubs. Findings pointed to partial validity of the protocol - with working memory and inhibition showing the best results. For Study 2, we used performance data from 51 elite female soccer players collected throughout a season of the first division league to assess predictive validity. Our protocol was able to partially replicate previous findings and added new insights on how working memory, processing speed and higher-level executive functions might play different roles for goalscoring and assist-making skills. Specifically, study 1 did not find a significant difference between elite and lower-division athletes in higher-order executive functions as in previous studies, but it did find on visual working memory and inhibitory control which weights towards higher demands of core executive functions. On the other hand, study 2 yielded significant results for processing speed and visual working memory to predict assists among elite soccer players, but not inhibitory control as previous findings suggested. Regardless, the proposed 4-instrument protocol showed adequate criterion and structural validity in both studies.

Deficits in specific executive functions manifest by severity in major depressive disorder: a comparison of antidepressant naïve inpatient, outpatient, subclinical, and healthy control groups

Introduction

Previous research has highlighted the executive function (EF) deficits present in depressed patients; however, conflicting results exist regarding the impact of depression severity on the size of these deficits. This study aimed to compare deficits in EF between antidepressant naïve inpatient and outpatient depressed, a group with subclinical depression symptoms, and a healthy control group while controlling for education, sex, and age.

Methods

In cross-sectional research, 245 antidepressant naive participants (46 inpatient, 68 outpatient, 65 subclinical, and 67 healthy control individuals) were recruited by convenience sampling. The Structured Clinical Interview for DSM-5 Disorders (SCID-5) and Beck Depression Inventory-II (BDI-II) were used to assess depression. EF was measured using several neuropsychological tests, including the Stroop Color-Word Test, the Wisconsin Card Sorting Test, and the N-back Test, which assessed the components of Inhibition, Shifting, and Updating, respectively. Multivariate analysis of covariance revealed a significant difference between the groups in EF components (p < 0.001). Pairwise comparisons further showed that inpatient and outpatient patients had more depressive symptoms and worse EF performance than subclinical and healthy control groups (p < 0.05).

Results

In the analysis of EF measures, a significant difference was found among the four groups, with post-hoc tests revealing variations in specific EF components. Overall, patients with more severe depressive symptoms show more deficits in EF. Additionally, correlations between clinical characteristics and EF measures varied across patient groups, but many correlations became non-significant after adjusting for the false discovery rate (FDR).

Discussion

This study emphasizes the impact of depression severity on deficits in the EF of depressed patients and at-risk populations. Consequently, it is important to consider executive dysfunctions as an underlying vulnerability in the development and persistence of depressive disorder.

Determining the effect of one decade on fitness of elite Austrian youth soccer players using propensity score matching

Current trends in attacking strategies and increases in external workload have led to a need for fast and well-conditioned athletes in modern soccer. More recently, progressions in speed, coordination, power and endurance were found over a decade in elite Austrian youth players. However, possible confounders such as relative age, maturation, learning effects, and academy philosophy may have influenced these changes. The present study aimed to determine the decade effect on fitness under statistical control of players' exact age, height, body mass, test location as well as total number of pretests and time interval between test and pretest. Players annually completed a battery of anthropometric, general and soccer-specific fitness tests. MANCOVA was calculated to identify the overall impacts of the covariates on fitness. To balance the covariates of initially 2,530 "former" (2002 to 2005) and 2,611 "recent" (2012 to 2015) players, 1:1 nearest neighbor propensity score (PS) matching was used, resulting in 587 U13, 573 U14, 475 U15, 325 U16, 262 U17, and 129 U18 matched pairs. The decade effect on fitness was assessed by independent t-tests and Cohen's d separately at each age group. Superior performances of recent players were found for linear sprint across all age categories (d = 0.154-0.476) as well as for agility (d = 0.125-0.340) and change-of-direction speed (d = 0.172-0.466) in U15 to U18. Reaction speed increased in U13 (d = 0.288) and U15 (d = 0.310). Flexibility reduced over the decade in all age categories (d = -0.151 to -0.589) and upper-limb power decreased (d = -0.278 to -0.347) in U13 and U14. Balancing the covariate distribution via PS matching generally confirmed previous findings, with fitness decade effects reflecting the athletic needs for modern soccer. Since fitness performance changed over time, reference values should be periodically updated. Coaches favor both physical and cognitive fast players nowadays. Thus, training should target all aspects of speed, without disregarding flexibility, upper-limb power and other preventive strategies that keep the players on the pitch.

Stop it! Relationship between sport expertise and response inhibition in elite athletes

Introduction

The dynamic structure of sport games forces players to make time-sensitive decisions and to initiate actions that may then have to be canceled in response to sudden changes in the game situation. Whether and up to which time already initiated movements can still be inhibited is an important criterion for game performance in elite sport. Research indicates that elite athletes show superior motor inhibition performance compared to recreational athletes. However, no study has examined whether differences also emerge among professional elite athletes themselves. Therefore, this study aimed to investigate whether motor inhibition performance is a differential feature among elite athletes, and whether inhibition performance increases with greater expertise.

Methods

In total of 106 elite athletes (ice hockey, basketball, volleyball, American football, handball, and soccer) completed a PC-based procedure to determine motor inhibition performance using the stop-signal reaction time (SSRT) task for hands and feet. In addition, an expertise score was determined for each elite athlete. Multiple linear regression was used to calculate the relationship between expertise and SSRT.

Results

Results showed that the expertise score of the elite athletes was between 3.7 and 11.7 out of 16 possible points (M_Expertise = 6.8 points, SD = 1.76). The average SSRT of the hands was 224.0 ms (SD = 35.0); of the feet, 257.9 ms (SD = 48.5). Regression results showed a significant relationship between expertise and SSRT (F_(2,101) = 9.38, p = 0.04, R² = 0.06). SSRTs of the hands were significant predictors of expertise (b = -0.23, t = -2.1, p = 0.04).

Discussion

Taken together, results suggest that elite athletes with higher expertise outperform elite athletes with lower expertise, indicating that it is possible to differentiate within elite athletes with respect to inhibition performance of the hands. However, whether expertise affects inhibition performance or vice versa cannot be answered at present.

The role of inhibitory control in sport performance: Systematic review and meta-analysis in stop-signal paradigm

Inhibitory control is an executive function that is closely and bidirectionally related to sports practice. The objective of this systematic review and meta-analysis was to study the effect of this relationship when response suppression is assessed within the Stop-Signal Paradigm. Twenty-four articles met the inclusion criteria and were selected for qualitative analysis, of which 11 studies were further analyzed through meta-analytic techniques. The standardized mean difference (SMD) was estimated for the stop-signal reaction time, and the influence of moderator variables was assessed. Athletes showed shorter stop-signal reaction time than non-athlete controls (SMD=0.44; 95% CI=0.14, 0.73), and this effect was mediated by age (SMD=-0.56; 95% CI=-1.11, -0.01). Athletes' superior stop-signal reaction time may be a result of extensive practice in cognitively demanding competitive environments. Young athletes can benefit the most from sports practice. In addition, engaging individuals in more cognitively demanding activities may obtain better response suppression enhancements, although the evidence in the stop-signal task is limited. Finally, some stop-signal task methodological aspects should be considered in future research.

An assist for cognitive diagnostics in soccer (Part II): Development and validation of a task to measure working memory in a soccer-specific setting

Cognitive diagnostics is of increasing interest to researchers and practitioners in the context of talent identification and performance enhancement in professional soccer. Research addressing the relevance of cognitive skills for sports performance has been based on the cognitive component approach (i.e., general cognitive processes) and the expert performance approach (i.e., sport-specific cognitive processes). Following the aim to combine the strengths of both approaches, we have previously developed and validated tasks to measure inhibition and cognitive flexibility in a soccer-specific setting, including a soccer-specific motor response. In line with the broad consistency on three core executive functions, this further development of diagnosing executive functions is to be completed with a task for the assessment of working memory. For this purpose, 60 amateur players with a soccer experience of at least one competitive season (M _age = 25.95, SD _age = 4.59) first conducted a computer-based version of the n-back (3-back) task followed by a 3-back task that required a soccer-specific motor response (i.e., pass) performed in a soccer-specific setting (i.e., SoccerBot100). Results show good reliability for both tasks. With regard to convergent validity, significant correlations between the computerized and soccer-specific task could be determined in target trials for response time (r = 0.446) and accuracy (r = 0.401). Thus, the soccer-specific n-back task can be considered a potentially valid instrument for assessing working memory and potentially allows soccer clubs to diagnose the three core executive functions in a consistent soccer-specific setting.

An Assist for Cognitive Diagnostics in Soccer: Two Valid Tasks Measuring Inhibition and Cognitive Flexibility in a Soccer-Specific Setting With a Soccer-Specific Motor Response

In professional soccer, players, coaches, and researchers alike recognize the importance of cognitive skills. Research addressing the relevance of cognitive skills has been based on the cognitive component skills approach (i.e., general cognitive processes) or the expert performance approach (i.e., sport-specific cognitive processes). Our project aimed to combine the strengths of both approaches to develop and validate cognitive tasks measuring inhibition and cognitive flexibility in a soccer-specific setting with a soccer-specific motor response. In the main study 77 elite youth soccer players completed a computerized version of the standard flanker and number-letter tasks as well as flanker and number-letter tasks requiring a soccer-specific motor response (i.e., pass) in a soccer-specific setting (i.e., the SoccerBot360). Results show good reliability for both tasks. For the SoccerBot360 number-letter task, switch effects for response times and accuracy and acceptable convergent validity were shown. A flanker effect for response time but not accuracy was apparent. Due to no acceptable convergent validity, the flanker task was revised (i.e., adaptation of stimuli) and 63 adult soccer players participated in a follow-up validation study in the SoccerBot100. The revised flanker task showed the flanker effect for response time, but not for accuracy. However, acceptable convergent validity for response time was present. Thus, the soccer-specific number-letter and to some extent the soccer-specific flanker task show potential to be used as a valid cognitive diagnostic tool by soccer clubs.

Inhibition and Calendar Age Explain Variance in Game Performance of Youth Soccer Athletes

The assessment of core executive functions (EFs; i.e., inhibition, working memory, cognitive flexibility) has often been presented as a diagnostic tool for evaluating cognitive functions in recent publications. For example, EFs are essential in soccer because players must quickly adapt, change strategies, and inhibit responses in rapidly changing game situations. Previous research has shown relations between (subjectively rated) game performance and the EFs of soccer players. Nevertheless, the previous studies' samples were heterogeneous in their performance level (experts vs. amateurs), and the ratings were rather unsystematic (no validated rating protocol). Therefore, the current study aimed to predict soccer players' game performance (i.e., systematically rated by coaches) with the help of EF performance. Therefore, we assessed the game performance (small-sided game, Game Performance Assessment Instrument [GPAI]) and EFs (inhibition: flanker task; working memory: 3-back task; cognitive flexibility: number-letter task) of 94 male soccer players (12-19 years old) from Germany's highest competitive level. Multiple regression model results indicate that inhibition (i.e., flanker effect) and calendar age explain ~18% of players' game performance variance. Results have to be interpreted with regard to the age-dependency of game performance and EFs. In conclusion, even though the results are based on a cross-sectional study, it appears that calendar age needs to be considered when assessing EFs.

Kognitionspsychologie im Fußball

Zusammenfassung. Anhand des Themas Kognitionspsychologie im Fußball ist es Ziel dieses Beitrags deutlich zu machen, warum es sinnvoll ist, dass Forschung und Praxis der Sportpsychologie und die entsprechenden Akteure integriert und eng zusammenarbeiten. Wir stellen konkrete Überlegungen vor, wie wir diesem Anspruch gerecht werden könnten und nehmen dabei auf ein aktuelles Projekt im Nachwuchsleistungsfußball Bezug. Dabei gehen wir zunächst auf ausgewählte theoretische Grundlagen der Kognitionspsychologie sowie empirische Befunde zur Rolle von Kognitionen und insbesondere der exekutiven Funktionen im Fußball ein, stellen dann Vorteile der Integration von Forschung und Praxis vor, um abschließend konkrete Anstöße zu einer möglichen Umsetzung einer verstärkten Integration von Forschung und Praxis zu geben.

The design fluency test: a reliable and valid instrument for the assessment of game intelligence?

The design fluency test (DFT) has been reported to predict successful sports performance of soccer players and has therefore been in the spotlight of sport psychology research. There is, however, a lack of research regarding the psychometric properties of the DFT in elite sports. Thus, the aim of this research was to provide findings of test–retest reliability, practice effects and the diagnostic power of the DFT. Multiple studies of youth and adult elite athletes, as well as nonathlete students, were conducted in applied settings. Test–retest relationship demonstrated poor to acceptable short-term and long-term correlations. Furthermore, significant changes between test and retest were obtained in some variables that differed among samples. The differential value of the DFT was corroborated by significant differences between adolescent students and adolescent elite soccer players. Regarding the prospective value, significant partial correlation coefficients were found between DFT scores and volleyball performance in adult elite players. Although our research partially confirmed previous findings on the differential and prospective power of the DFT, the findings on test–retest reliability indicate that the DFT cannot be recommended for application in sports. The psychometric properties—in particular the findings on test–retest reliability—of the DFT have to be improved before research can be carried out on the application for the selection of team sport athletes and for the prediction of future success in team sports. Further research is needed to develop a scientific instrument for the assessment of game intelligence.

Executive Functions of Swedish Counterterror Intervention Unit Applicants and Police Officer Trainees Evaluated With Design Fluency Test

Executive functions (EF) represent higher order top-down mechanisms regulating information processing. While suboptimal EF have been studied in various patient groups, their impact on successful behavior is still not well described. Previously, it has been suggested that design fluency (DF)-a test including several simultaneous EF components mainly related to fluency, cognitive flexibility, and creativity-predicts successful behavior in a quickly changing environment where fast and dynamic adaptions are required, such as ball sports. We hypothesized that similar behaviors are of importance in the selection process of elite police force applicants. To test this hypothesis, we compared elite police force applicants (n = 45) with a control group of police officer trainees (n = 30). Although both groups were better than the norm, the elite police force applicants had a significantly better performance in DF total correct when adjusting for sex and age [F(1,71) = 18.98, p < 0.001]. To understand how this capacity was altered by stress and tiredness, we re-tested the elite police force applicants several days during an extreme field assessment lasting 10 days. The results suggested that there was a lower than expected improvement in DF total correct and a decline in the DF3-subtest that includes a larger component of cognitive flexibility than the other subtests (DF1 and DF2). Although there was a positive correlation between the baseline session and the re-test in DF3 [r(40) = 0.49, p = 0.001], the applicants having the highest scores in the baseline test also displayed the largest percentage decline in the re-test [r(40) = -0.46, p = 0.003]. In conclusion, our result suggests that higher order EF (HEF) that include cognitive flexibility and creativity are of importance in the application for becoming an elite police officer but relatively compromised in a stressful situation. Moreover, as the decline is different between the individuals, the results suggest that applicants should be tested during baseline conditions and during stressful conditions to describe their cognitive capacity fully.

Relative Age Effect in Elite German Soccer: Influence of Gender and Competition Level

The relative age effect (RAE) is associated with (dis)advantages in competitive sports. While the RAE in elite male soccer reveals a skewed birthdate distribution in relation to a certain cut-off date, research of RAE in elite female soccer is affected by small number of samples and conflicting results. The purpose of this study was to investigate the RAE in elite adult German soccer regarding gender and competition level. The sample comprised 680 female and 1,083 male players of the two top German leagues during the 2019/20 season and German national teams (A-Team to Under 19). Differences between the observed and expected birthdate distributions were analyzed using chi-square statistics and effect sizes followed by calculating odds ratios. Results showed a statistically significant RAE with small effect size across all players included for both genders (female players: P < 0.001, W = 0.16, male players: P < 0.001, W = 0.23). The identified RAE was based on an over-representation of players born at the beginning of the year. According to gender and competition level, RAEs were more pronounced in German male soccer. While significant RAEs were found among males in the first two leagues (first league: P < 0.001, W = 0.19, second league: P < 0.001, W = 0.26), the RAE of females was more pronounced in the second league (first league: P = 0.080, W = 0.16, second league: P = 0.002, W = 0.20). The analysis of RAE regarding the national teams revealed a statistically significant RAE with large effect size for only the youngest investigated age group of male players (Under 19: P = 0.022, W = 0.52). Our data show an RAE in female and male German adult soccer, which could be accompanied by a loss of valuable elite players during the youth phase of the career. Consequently, the pool of talented players at the adult level would be limited.