Is there a relationship between executive functions and resilience in youth elite soccer players?

BACKGROUND

While the relationship between cognitive performance and sport performance in youth elite soccer players has proponents as well as opponents, many aspects of this relationship remain unclear. Therefore, this quasi-experimental study wants to contribute to this relationship including the psychological aspect of resilience when investigating youth elite soccer players during an assessment selection for a representative team.

METHODS

Questionnaires as well as computer-based tests were conducted.

RESULTS

Results of this study showed no relationship between resilience and executive function in youth elite soccer players. Furthermore, no differences in executive functions or in resilience were found between those players who are selected for a representative team and those who were not selected.

CONCLUSION

The results indicate that further research needs to be conducted to clarify possible relationships in more detail.

Differences between hemispheres and in saccade latency regarding volleyball athletes and non-athletes during saccadic eye movements: an analysis using EEG

BACKGROUND

The saccadic eye movement is responsible for providing focus to a visual object of interest to the retina. In sports like volleyball, identifying relevant targets quickly is essential to a masterful performance. The training improves cortical regions underlying saccadic action, enabling more automated processing in athletes.

OBJECTIVE

We investigated changes in the latency during the saccadic eye movement and the absolute theta power on the frontal and prefrontal cortices during the execution of the saccadic eye movement task in volleyball athletes and non-athletes. We hypothesized that the saccade latency and theta power would be lower due to training and perceptual-cognitive enhancement in volleyball players.

METHODS

We recruited 30 healthy volunteers: 15 volleyball athletes (11 men and 4 women; mean age: 15.08 ± 1.06 years) and 15 non-athletes (5 men and 10 women; mean age: 18.00 ± 1.46 years). All tasks were performed simultaneously with electroencephalography signal recording.

RESULTS

The latency of the saccadic eye movement presented a significant difference between the groups; a shorter time was observed among the athletes, associated with the players' superiority in terms of attention level. During the experiment, the athletes observed a decrease in absolute theta power compared to non-athletes on the electrodes of each frontal and prefrontal area.

CONCLUSION

In the present study, we observed the behavior of reaction time and absolute theta power in athletes and non-athletes during a saccadic movement task. Our findings corroborate the premise of cognitive improvement, mainly due to the reduction of saccadic latency and lower beta power, validating the neural efficiency hypothesis.

Effects of carbohydrate drinks ingestion on executive function in athletes: a systematic review and meta-analysis

Background

Carbohydrates are often used as boosters for endurance and high-intensity exercise. However, it is unclear whether carbohydrate drinks intake before or during exercise can affect specific domains of cognitive function, such as Executive Function (EF).

Methods

Following the guidance of PRISMA 2020, we searched six major databases including PubMed, WOS, SPORTDiscus, Cochrane, Embase, and Scopus. Outcomes were presented in the form of Reaction Time (RT), Accuracy (ACC), and Scores (Score) for performing EF tests. Effect sizes were calculated from the test results of EF and expressed as standardized mean differences (SMDs). After analyzing the overall results, we performed subgroup analyses based on the athletes' program characteristics.

Results

After retrieving a total of 5,355 articles, ten randomized controlled trials (RCTs) were identified and included in this review. The overall results showed that the intake of carbohydrate drinks before or during exercise did not have a significant effect on the reduction of EF after exercise (ACC (-0.05 [-0.27, 0.18]); RT (-0.18 [-0.45, 0.09]); Score (0.24 [-0.20, 0.68])). The subgroup analyses based on open skill sports and close skill sports also showed invalid results, but the results of RT ended up with different preference (ACC of open skill sports athletes (-0.10 [-0.34, 0.14]); RT of open skill athletes (-0.27 [-0.60, 0.07]); RT of close skill athletes (0.29 [-0.24, 0.82])).

Conclusion

The intake of 6-12% of single or mixed carbohydrates before or during exercise was not significantly effective in reducing the decline in EF after exercise. Our findings may have been influenced by the type of intervention, dose, mode of administration, or individual variability of the included subjects.

The effects of a smartphone game training intervention on executive functions in youth soccer players: a randomized controlled study

Cognitive training primarily aims to improve executive functions (EFs). It has become a popular research topic, as previous studies have provided preliminary evidence that EFs relate to sports performance. However, whether a domain-generic cognitive training intervention can improve EFs in high-performance athletes is still unclear. The present randomized controlled study aimed to examine the effects of an eight-week (5 min/day, 5 days/week) smartphone-based domain-generic cognitive training intervention (i.e., the smartphone game "Fruit Ninja") on EFs in youth soccer athletes (N = 33; intervention: n = 15, passive control: n = 18; German youth soccer academy). We assessed working memory (3-back task), inhibition (Flanker & Go/NoGo task), and cognitive flexibility (number-letter task) in a pre-post design with computerized tasks. The results showed no significant time x group differences attributable to the cognitive training between the intervention group and the control group, except for a response time variable of the Go/NoGo task. These preliminary results do not suggest an application of CT as a smartphone-based game to improve EFs performance in soccer players. However, more research is needed to establish the efficacy of domain-specific interventions in high-level team sport athletes.

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.

Effects of speed, agility and quickness training programme on cognitive and physical performance in preadolescent soccer players

The aim of the present study was to investigate the effect of a short-term (4 weeks) non-soccer-specific training programme based on speed, agility and quickness (SAQ) and a soccer-specific training programme based on small-sided games (SSG) on cognitive and physical performance in preadolescent soccer players. Twenty-one participants were randomly assigned to SAQ group (n = 11) or SSG group (n = 10). They were tested pre and post interventions on physical (5 m sprint, 20 m sprint and sprint with turns of 90°) and cognitive (inhibitory control by means of the Flanker task and perceptual speed by means of the visual search task) performances. Although no significant time x group interactions were observed, the main effect of time was significant for cognitive performance and 5 m and 20 m sprint, showing improvements after both SAQ and SSG. These findings highlight that 4 weeks of SAQ training programme induced comparable improvements in cognitive and physical performance with respect to a soccer-specific training programme based on SSG in preadolescent soccer players. Non-sport-specific activities targeting speed, agility and quickness combined with cognitive engagement (i.e., SAQ) should be useful strategies as soccer-specific activities to be included within a soccer training programme for promoting both physical and cognitive domain in preadolescent individuals.

Visual occlusion effects on youth football players’ performance during small-sided games

This study aimed to explore how youth players’ physical, technical and positional performance may be affected by visual occlusion when playing under different SSG pitch sizes. Under-15 players performed two experimental scenarios: a) normal situation, without visual occlusion; b) visual occlusion, by using an eye patch in the eye corresponding to the dominant foot. These scenarios were tested in a small (40x30m) and a larger pitch (50x35m). Players’ positional data was used to compute tactical and time-motion variables. In addition, technical analysis was comprised using video footage. Playing with visual occlusion in the larger pitch size induced higher distance covered while walking but lower running distance (p < .05). Although no statistically significant effects were identified between the normal and visual occlusion conditions for the tactical behaviour and technical performance a lower number of successful passes (small to moderate effect sizes) and higher regularity in the distance to the opponent’s team centroid (moderate effect size) were found with visual occlusion. Players covered more distance and achieved higher maximum speed in the larger compared to the small pitch (moderate to large effect size, p < .05), while also increasing their distance to both team’s centroid and increasing the regularity to these distances (moderate to large effect size, p < .05). Overall, despite similar effects for tactical and technical variables, some important practical information can be depicted. Accordingly, coaches may use the visual occlusion to promote more stable and regular behaviors while decreasing the physical demands. Larger pitches may be used to increase the distance between players’ and teams, as well as to induce higher physical load in both the normal and visual occlusion conditions. From the technical perspective, coaches may design smaller pitches to emphasize the use of the non-dominant foot during the occlusion scenario and promote the pass during the normal scenario.

Mathematical models to identify high-performance players for the Brazilian under-19 men's volleyball team

The objective of this study was to identify parameters that best discriminate between selected and non-selected players for the Brazilian under-19 men's volleyball team and propose mathematical models to identify high-performance players. To this end, 18 selected (16.89±0.96 years) and 138 non-selected (16.91±0.74 years) players for the under-19 team were assessed for the training profile, anthropometric profile, and physical performance level. The discriminant function analysis was used to build the models, with a significance of α<0.05. The spike jump reach showed a greater correlation with the discriminant scores obtained in the two models (r=0.701; r=0.782). The 10 variables included in Model 1 helped identify 88.9% of the players selected in their group of origin; Model 2 - obtained by the spike jump reach and duration of playing experience - identified 83.3% of the players selected. Therefore, coaches should be aware that differences between the selected and non-selected players are multi-factorial, with the spike jump reach being the most relevant assessment factor. Furthermore, good players for the selection can be identified using the two models: Model 1 promises greater success with ten assessments, whereas Model 2 allows the identification of suitable players for the under-19 men's volleyball team with only two simple assessments.

Associations between bio-motor ability, endocrine markers and hand-specific anthropometrics in elite female futsal players: a pilot study

BACKGROUND

The second-to-fourth digit ratio (2D:4D) has been calculated for individual athletes and sports, but it has not been investigated in futsal performance. Therefore, the aim of this study was to investigate any relationships between 2D:4D of the dominant and non-dominant hands and physical capacity performances, selected functional variables and hormone concentrations in elite female futsal players.

METHODS

Twenty-four elite female futsal players were measured for 2D:4D in the dominant (2D:4D_D) and non-dominant (2D:4D_ND) hand. The futsal specific performance test (FSPT), hand-grip strength (HGS) and aerobic power were also assessed. In addition, selected circulatory hormones were measured (estradiol, cortisol, growth hormone and insulin like growth factor-1). Pearson's correlation test was used to identify correlational relationships.

RESULTS

Total test-time and performance time (total time + penalty time) for the FSPT showed a significant correlation with 2D:4D_D (r = 0.53, p = 0.005 and r = 0.55, p = 0.003, respectively). HGS_ND also displayed a significant correlation with the 2D:4D_D (r = 0.59, p = 0.002). Aerobic power and time spent running on the treadmill also showed a significant relationship with 2D:4D_ND (both, r = 0.54, p = 0.006). Cortisol showed a significant correlation with 2D:4D_D (- 0.58, p = 0.003) and 2D:4D_ND(- 0.52, p = 0.008).

CONCLUSIONS

The measurement of 2D:4D ratio could be an important factor in determining potential performance attributes and talent identification of elite female futsal players. Further studies are needed in this area to further examine the results presented here.

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.

Questionable Utility of the Eccentric Utilization Ratio in Relation to the Performance of Volleyball Players

The difference between squat jump (SJ) and countermovement jump (CMJ), termed eccentric utilization ratio (EUR), is frequently suggested as an outcome that can be used in athletic training design. Unlike performance in SJ and CMJ, which is associated with sports performance, the association between EUR and sports performance is almost unexplored. This study aimed to investigate whether EUR is associated with performance in approach jump, linear sprint and change of direction (CoD) tasks in volleyball players. Forty-five male volleyball players performed SJ, CMJ, 25 m linear sprint, approach jump and two CoD tasks (505 test and modified T-test). EUR was calculated based on jump height, peak power, peak force and average power. SJ and CMJ variables showed moderate to high correlation with approach jump performance (r = 0.42–0.70), small correlation with modified T-test (r = 0.33–0.40) and small to moderate correlation with sprint time (r = 0.35–0.49). EUR showed only small associations with performance variables (r = 0.31–0.34). In all linear regression models with performance outcomes as dependent variables, the CMJ height was always the only statistically significant predictor. Our results support the recent arguments that the EUR offers limited insight into the neuromuscular capabilities of athletes.

Regions of interest selection and thermal imaging data analysis in sports and exercise science: a narrative review

OBJECTIVE

Infrared thermography (IRT) is a non-invasive, contactless and low-cost technology that allows recording of the radiating energy that is released from a body, providing an estimate of its superficial temperature. Thanks to the improvement of infrared thermal detectors, this technique is widely used in the biomedical field to monitor the skin temperature for different purposes (e.g. assessing circulatory diseases, psychophysiological state, affective computing). Particularly, in sports and exercise science, thermography is extensively used to assess sports performance, to investigate superficial vascular changes induced by physical exercise, and to monitor injuries. However, the methods of analysis employed to treat IRT data are not standardized, and hence introduce variability in the results.

APPROACH

This review focuses on the methods of analysis currently used for thermal imaging in sports and exercise science.

MAIN RESULTS

Firstly, the procedures employed for the selection of regions of interest (ROIs) from anatomical body districts are reviewed, paying attention also to the potentialities of morphing algorithms to increase the reproducibility of thermal results. Secondly, the statistical approaches utilized to characterize the temperature frequency and spatial distributions within ROIs are investigated, showing their strengths and weaknesses. Moreover, the importance of employing tracking methods to analyze the temporal thermal oscillations within ROIs is discussed. Thirdly, the capability of employing procedures of investigation based on machine learning frameworks on thermal imaging in sports science is examined.

SIGNIFICANCE

Finally, some proposals to improve the standardization and the reproducibility of IRT data analysis are provided, in order to facilitate the development of a common database of thermal images and to improve the effectiveness of IRT in sports science.

Differences in inhibitory control and motor fitness in children practicing open and closed skill sports

The aim of the present study was to investigate the differences between types of sport (i.e., closed vs. open skills sport) on inhibitory control and motor fitness in children. Forty-nine children were allocated into three groups based on their sports participation, which comprised an open skill sport group, a closed skill sport group, and a sedentary group. Participants were tested on cognitive performance (inhibitory control by the Flanker task) and motor fitness (reaction time, speed, agility, power, balance). Open skill sport group appeared to display higher inhibitory control (response time and accuracy of incongruent condition of the Flanker task) and motor fitness performance (reaction time, speed, agility, power) than sedentary group, whereas its superiority over closed skill sport group was found only in speed and agility. Moreover, closed skill sport group had only a better reaction time than sedentary group. Our data supports the framework according to which cognitive demands in complex motor actions may contribute to explain the beneficial effects of exercise on inhibitory control. This might suggest that the complexity of the environment (typical in open skill sports) in which sport training is performed plays a key role for both cognitive and motor development in children.

Relationship between Cognitive Functions and Sport-Specific Physical Performance in Youth Volleyball Players

The aim of this study was to investigate the relationship between basic cognitive functions and sport-specific physical performance in young volleyball players. Forty-three female volleyball players (age 11.2 ± 0.8 years) were tested for cognitive performance by measuring simple reaction time (clinical reaction time), executive control (Flanker task), and perceptual speed (visual search task). Moreover, a set of tests was used to assess physical abilities as volleyball-specific skills (accuracy of setting, passing, and serving) and motor skills (change of direction, vertical jump, and balance). A cumulated value for both cognitive and sport-specific physical performance tests was computed by adding up each test’s domain outcomes. Pearson’s r correlation analysis showed a large positive correlation (r = 0.45, d-value = 1.01) of the cumulated score summarizing cognitive functions with the cumulated score summarizing sport-specific physical performance. Moreover, small-to-medium correlations (d-value from 0.63 to 0.73) were found between cognitive and motor skills. Given the cumulative scores, these results suggest that volleyball athletes with superior basic cognitive functions present better sport-specific physical performance. Our findings encourage to extend the knowledge of the associations between cognitive and motor skills within a sports performance context.

Relationships of the 5-Jump Test (5JT) Performance of Youth Players With Volleyball Specific' Laboratory Tests for Explosive Power

Volleyball involves movements with and/or without horizontal approaches (i.e., spike jumps, jump setting, blocking). The 5-jump test (5JT) was suggested to assess lower limb explosive power of athletes competing in some disciplines (e.g., soccer, judo, running). It appears that no previous study has investigated the 5JT performance components in volleyball players. This study aimed to test the relationship between 5JT performance and two specific laboratory tests for explosive power (i.e., countermovement jump [CMJ] and squat jump [SJ]). Forty volleyball players (boys, mean age: 12.4 ± 0.8 years) were tested for 5JT, CMJ, and SJ tests. 5JT performance was expressed in absolute terms (m), and relative to leg length (5JT_LL) and body mass (5JT_BM). The SJ and CMJ tests were evaluated using the optojump photoelectric cells and the following data were collected: peak power (Pp) of jump (W, W.kg^-0.67), peak jumping force (F_peak, N), peak jumping velocity (V_peak, m/s), peak heights of CMJ and SJ (CMJ_H and SJ_H, respectively, cm). Only significant (p < .05) Pearson product-moment correlations (r) > 0.30 were considered. 5JT performance was significantly correlated with SJ, V_peak (r = 0.90), SJ_H (r = 0.88), Pp [W.kg^-0.67 (r = 0.86), W (r = 0.72)], F_peak (r = 0.45); and CMJ, V_peak (r = 0.82), CMJ_H (r = 0.80), Pp [W.kg^-0.67 (r = 0.89), W (r = 0.85)], F_peak (r = 0.73). 5JT_LL values were significantly related to SJ, Pp [W (r = 0.81), W.kg^-0.67 (r = 0.74)], V_peak (r = 0.82); and CMJ, Pp [W (r = 0.73), W.kg^-0.67 (r = 0.84)], V_peak (r = 0.75), F_peak (r = 0.67)]. 5JT_BM values were significantly related to SJ, Pp (W, r = −0.43). To conclude, in youth volleyball players, the 5JT may be viewed as an explosive strength diagnostic instrument under field circumstances.

Changes of Mood and Cognitive Performance before and after a 100 km Nighttime Ultramarathon Run

Ultramarathons are becoming an increasingly popular endurance sport. Year after year, the demands on athletes’ skills and endurance increase. Ultramarathons are particularly taxing on athletes’ psychological functioning. This study assessed the relationships between taking part in a nighttime ultramarathon and changes in mood and cognitive functioning. The study included 20 experienced runners aged 26–57 (M = 37.29; SD = 7.94) who had M = 7.08, SD = 5.41 (range 3–44) years of experience running. There were 18 men and 2 women. The mood states were measured twice, just before the start of the run and shortly after crossing the finish line, using the Polish version of the UMACL UWIST Mood Adjective Checklist by Mathews, Chamberlain, and Jones. To assess cognitive functioning, the Stroop Color and Word Test and “Forward digit span” subtest from the Wechsler Adult Intelligence Scale were used. We observed statistically significant changes in the mood of the runners: tense arousal, associated with the experienced stress, was significantly higher before the run than immediately after the finish. Moreover, we observed an improvement in cognitive functioning after finishing the 100 km run on both of the trials on the Stroop color word test and on the forward digit span test.

Mental fatigue impairs physical activity, technical and decision-making performance during small-sided games

The aim of this study was to investigate the effects of mental fatigue on physical activity, technical and decision-making performance during small-sided games. Nine sub-elite soccer players were enrolled in the study. The players performed two small-sided games on two occasions within a crossover experimental design. Before each game, they underwent a mental fatiguing task (Stroop task) and a control task (documentary watching) in a randomized, counterbalanced order. Players' physical activity, technical, and decision-making performance were obtained during small-sided games by GPS and video scouting. Results showed that distance in acceleration covered per min, negative passes, passing accuracy, and shot accuracy were likely impaired than control task after a mental fatiguing protocol. Decision-making performance of negative passes, passes accuracy, and dribbling accuracy resulted also likely decreased compared with control task. These findings demonstrated that mental fatigue impacted on technical, GPS-derived, and soccer-specific decision-making performance during SSG. In conclusion, avoiding cognitively demanding tasks before playing soccer-specific activities may be advisable to preserve players' physical activity, technical, and decision-making skills.