The dribbling agility test as a potential tool for evaluating the dribbling skill in young soccer players

The Reliability of Linear Speed with and without Ball Possession of Pubertal Soccer Players

Reliable fitness tests with low day-to-day and trial-to-trial variation are a prerequisite for tracking a player's performance or for identifying meaningful changes in training interventions. The present study examined the inter- and intra-session reliability of 30 m linear speed with and without ball possession as well as the reliability of a specific performance index of pubertal soccer players. A total of 40 pubertal (14.87 ± 1.23 years old) male soccer players performed two testing sessions (test-retest) separated by 72 h. Both testing sessions included a protocol consisting of two maximal trials of 30 m linear speed with and without ball possession. A performance index, indicating the difference between the two speed tests, was also calculated using two different equations (delta value and percentage value). The relative and absolute inter-session reliabilities were good/high for all testing variables (ICC = 0.957-0.995; SEM% = 0.62-8.83). There were also good/high relative and absolute intra-session reliabilities observed for all testing variables (ICC = 0.974-0.987; SEM% = 1.26-6.70%). According to the Bland-Altman plots, the differences between test-retest and trials for all observations were within the defined 95% limits of agreement. The reliable testing protocols and performance index for the evaluation of linear speed with and without ball possession, observed in this study, may be used in speed monitoring and training planning of pubertal soccer players.

Development and trainability of agility in youth: A systematic scoping review

Background

Agility is acknowledged as a crucial factor of performance in various open skill sports in both adult and youth athletes. However, despite its significance for sports performance the development and the trainability of agility are under-researched within the pediatric literature. A systematic scoping review was considered most appropriate to provide researchers and practitioners with an overview of the current body of literature approaching agility in youth.

Objectives

The objectives of this scoping review were to map the extent, range, and nature of existing evidence regarding trainability and "natural" development of agility and to summarize corresponding study results.

Methods

The scoping review protocol was pre-registered at Open Science Framework. Systematic searches were conducted using the databases PubMed, Scopus, ProQuest, Web of Science, SURF, and SPONET to identify sources covering agility in youth. Among other inclusion criteria, only references applying unplanned agility concepts were included.

Results

Ultimately, 41 reports were included comprising 23 observational studies, 14 experimental studies, and 4 references of secondary research. A total of 3,087 subjects were assessed in the included studies. Subject groups were predominantly male, above 10 years of age, and soccer athletes. Outcomes of observational studies indicate an effect of age and maturation on agility performance resulting in a non-linear "natural" development of agility. Furthermore, relationships between contributing perceptual-cognitive factors and agility performance tend to increase with progressing age, whereas relationships between physical factors and agility performance diminish. Evidence of training studies suggests that agility is trainable in youth, albeit with various underlying mechanisms.

Conclusions

This systematic scoping review is the first mapping of the body of literature about agility in youth. It outlines the current evidence base, reveals research gaps, and points out future directions to support researchers and practitioners in this field. Although, increasing research activity in this field is discernible, agility research in youth is still in its infancy. Considering the significance of agility for sports performance, future research is postulated to design evidence-based strategies for long-term agility development in young athletes.

Screening Youth Soccer Players by Means of Cognitive Function and Agility Testing

Talent identification in sports is a heavily debated topic. Previous studies have separately explored either executive functions or gross motor skills to predict the success of top-level soccer players or, more generally, to characterize elite performance in soccer. However, at mid-childhood, the possibility to scope sport-specific requirements remains elusive. We aimed in this study to investigate a valid and simple method of testing for a unique combination of cognitive and speed abilities for identifying promising soccer players at mid-childhood. We measured cognitive functions by means of a Stroop smartphone application and agility with a T-Drill Ball-success test, in two groups of (a) elite- (n = 31) and (b) low-division (n = 37) Italian 7-year-old male soccer players. We administered the tests in a randomized order to both groups. We found better inhibitory control, cognitive flexibility and soccer-specific agility in high-division versus low-division players (p < .001). Inhibitory response and agility were positively associated with the augmented quality of the performance from low-division players to high-division players (r = .55; p = .0001). These results suggest that, even at an early age, cognitive control together with soccer-specific skills is associated with better performance.

Assessing the Reliability and Validity of Agility Testing in Team Sports: A Systematic Review

Yepes, MM, Feliu, GM, Bishop, C, and Gonzalo-Skok, O. Assessing the reliability and validity of agility testing in team sports: A systematic review. J Strength Cond Res XX(X): 000-000, 2020-The aims of this systematic review were to (a) examine the reliability of the reactive agility tests and (b) analyze the discriminatory validity of the agility tests. A literature search was conducted following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). We explored PubMed, SPORTDiscus, and Cochrane Plus databases looking for articles about agility in team sports. After filtering for article relevance, only 42 studies met the inclusion criteria; 37 of which assessed the reliability of agility tests and 22 assessing their validity. Reliability showed a high intraclass correlation coefficient (ICC) in almost all studies (range 0.79-0.99) with the exception of 2 studies. In addition, other studies also assessed the reliability of decision time (ICC = 0.95), movement time (ICC = 0.92), and decision accuracy (ICC = 0.74-0.93), all of which exhibited acceptable reliability. Furthermore, these data show high discriminatory validity, with higher performance level players being faster than lower performance level players (mean = 6.4%, range = 2.1-25.3%), with a faster decision time (mean = 23.2%, range = 10.2-48.0%) with the exception of 1 study, and better decision accuracy (mean = 9.3%, range = 2.5-21.0%). Thus, it can be concluded that reactive agility tests show good reliability and discriminatory validity. However, most agility tests occur in simple contexts whereby only 2 possible responses are possible. Therefore, future research should consider creating more specific and complex environments that challenge the cognitive process of high-level athletes.