It's Time to Change Direction on Agility Research: a Call to Action

No Impact of Anthropometric and Fitness Factors on Speed-Agility in Young Soccer Players: Is It a Cognitive Influence?

PURPOSE

Agility in young soccer players has long been associated with physical attributes like strength, speed, and power. The aims of this study were to investigate the relationship between cognitive factors and agility performance in this unique population.

METHODS

39 young soccer players age 13.56 (SD 0.58) years were assessed for leg-muscle function (jump tests) and maturation status (peak height velocity). The Y-Agility Test, which included decision making in players, was used to measure performance. Cognitive factors such as perceptual skills and decision making were evaluated with the Y-Agility Test.

RESULTS

The linear regression showed an absence of significance between the Y-Agility Test and drop-jump contact (P = .283), Y-Agility Test and drop-jump flight (P = .185), Y-Agility Test and squat jump (P = .868), and Y-Agility Test and countermovement jump (P = .310). The linear mixed-model analyses suggested a difference between early-average maturers (P = .009) and early-late maturers (P = .005) but did not show a difference between average-late subjects (P = 1.000). Drop-jump flight did not show a difference in maturation (early-average P = 1.000; early-late P = 1.000; average P = 1.000). Squat-jump performance did not demonstrate any significance (early-average P = .618; early-late P = 1.000; P = 1.000). Countermovement-jump performance did not show any significance (early-average P = 1.000; early-late P = 1.000; average-late P = .492). Finally, agility performance does not show any significance between maturation levels (early-average maturer P = .450; early-late P = 1.000; average-late P = .830).

CONCLUSION

Agility in young soccer players appears to follow a nonlinear trajectory, with cognitive factors possibly playing a more significant role than previously thought.

Testing in Intermittent Sports-Importance for Training and Performance Optimization in Adult Athletes

ABSTRACT

Performance in intermittent sports relies on the interplay between multiple physiological systems determining the capacity to perform short explosive efforts as well as repeated intense actions with limited recovery over the course of an entire game. Testing should reflect these demands to allow for sport- and position-specific capacity analyses that eventually may translate into optimized training and improved performance. This may include individual load management and optimized training prescription, intensity targeting for specific positions or individual athletes, as well as benchmarking for monitoring of training progression and enhanced engagement of athletes. This review provides an overview of available tests in different exercise domains identified as relevant (from assessment of single explosive actions to intermittent endurance capacity), forming the basis for recommendations on how to compose a comprehensive yet feasible test battery that may be integrated into the seasonal competition and training plan. The test procedures should cover the performance spectrum of relevance for the individual athlete-also in team sports to account for positional differences. We emphasize the benefits of sport-specific tests, highlight parameters of importance for test standardization, and discuss how the applied test battery may be supplemented with secondary tests directed toward specific energy systems to allow for more in-depth analyses when required (e.g., in terms of an underperforming athlete). The synergy between testing and tracking of match performance (utilizing time-motion or global positioning systems) is highlighted, and although tracking cannot substitute for testing, combining the tools may provide a comprehensive overview of the physiological demands and performance during competition contextualized to the athletes' maximal exercise capacity.

The effects of rule changes in football-code team sports: a systematic review

Rule changes within football-code team sports aim to improve performance, enhance player welfare, increase competitiveness, and provide player development opportunities. This manuscript aimed to review research investigating the effects of rule changes in football-code team sports. A systematic search of electronic databases (PubMed, ScienceDirect, CINAHL, MEDLINE, and SPORTDiscus) was performed to August 2023; keywords related to rule changes, football-code team sports, and activity type. Studies were excluded if they failed to investigate a football-code team sport, did not quantify the change of rule, or were review articles. Forty-six studies met the eligibility criteria. Four different football codes were reported: Australian rules football (n = 4), rugby league (n = 6), rugby union (n = 16), soccer (n = 20). The most common category was physical performance and match-play characteristics (n = 22). Evidence appears at a high risk of bias partly due to the quasi-experimental nature of included studies, which are inherently non-randomised, but also due to the lack of control for confounding factors within most studies included. Rule changes can result in unintended consequences to performance (e.g., longer breaks in play) and effect player behaviour (i.e., reduce tackler height in rugby) but might not achieve desired outcome (i.e., unchanged concussion incidence). Coaches and governing bodies should regularly and systematically investigate the effects of rule changes to understand their influence on performance and injury risk. It is imperative that future studies analysing rule changes within football codes account for confounding factors by implementing suitable study designs and statistical analysis techniques.

Effects of a neuromuscular training program on the performance and inter-limb asymmetries in highly trained junior male tennis players

Background

The objective of this study was to assess the effectiveness of neuromuscular training on the performance of highly trainer junior tennis players.

Methods

Twelve male tennis players (age: 13.4 ± 0.36 years; weight: 50.2 ± 6.29 kg; height: 163 ± 4.41 cm) participated and were randomly divided into two groups. The experimental group (EG) performed neuromuscular training that included exercises for speed, strength, throws, agility, jumps and coordination twice a week for a duration of 10 weeks. Performance was evaluated using various variables, including bilateral and unilateral countermovement jump, 30 cm drop jump and horizontal jump, 505 change of direction test conducted with both the right and left legs, 20-m sprint, and overhead 3 kg medicine ball throw. Asymmetries were also evaluated during the unilateral tests. The impact of the training was assessed through the utilization of ANCOVA tests and effect size measurements.

Results

The results indicated a significant enhancement in the EG, specifically in bilateral vertical jump and horizontal jump, as well as explosive strength and speed. Conversely, the control group (CG) did not display similar advancements. Furthermore, there was no increase in asymmetries.

Conclusion

This suggests that the implementation of a neuromuscular training program could prove to be an effective approach in enhancing explosive power in the lower limbs among young competitive tennis players. Finally, this training program could contribute to the enhancement of their physical attributes in lower body of young tennis players.

Effects of six-week stroboscopic training program on visuomotor reaction speed in goal-directed movements in young volleyball players: a study focusing on agility performance

BACKGROUND

In team sports, deficits in visuomotor reaction speed are considered a significant and modifiable risk factor that can lead to decreased performance and an increased risk of injuries. Thus, identifying effective methods to enhance visuomotor abilities is crucial. The main objective of this research was to investigate the impact of a six-week stroboscopic intervention on visuomotor reaction speed in goal-directed specific movements based on agility among young volleyball players. Additionally, the study aimed to explore the impact of saccade dynamics on visuomotor reaction speed performance throughout the experiment.

METHODS

There were 50 athletes (26 males and 24 females) with an average age of 16.5 years (± 0.6) who participated in this study. Over a six-week training period, athletes performed volleyball-specific training either wearing stroboscopic glasses (intervention) or under normal visual conditions (control). Prior to and after the training period, the agility tests based on change-of-direction speed (CODS) and reactive agility (RA) were used to identify visuomotor reaction speed performance. To measure agility performance a five-repetition shuttle run to gates was conducted. The REAC-INDEX, which represents visuomotor reaction speed, was analyzed as the resulting difference between the CODS test and the RA test. To elicit saccadic dynamics, a laboratory visual search task was performed.

RESULTS

A significant GROUP×TIME interaction was observed for the REAC-INDEX (p = 0.012, ηp2 = 0.13). ANCOVA analyses revealed significant GROUP differences, indicating improved post-training REAC-INDEX results (p = 0.004, d = 0.87), regardless of gender. Training-induced modulations in saccade acceleration did not reach significance, but a significant relationship was observed between changes in saccade acceleration and changes in the REAC-INDEX (r = -0.281, p = 0.048), indicating that higher performance gains following training were associated with a stronger increase in saccade acceleration.

CONCLUSIONS

This study demonstrates that stroboscopic training effectively enhances visuomotor reaction speed in goal-directed movements based on agility. Furthermore, visuomotor reaction speed gains could potentially be mediated by saccade dynamics. These findings provide valuable insights into the effectiveness of stroboscopic eyewear for training sport-specific visuomotor skills among young volleyball players.

Are change of direction speed and agility different abilities from time and coordinative perspectives?

This study aimed to test whether agility and change of direction speed (COD) are independent capacities using the same movement pattern (1) in terms of the completion time and (2) the entropy. Seventeen semi-professional female football players participated in the study. The agility task consisted of a Y-shaped (45° COD) task with three possible exit options (center, right and left) performed pre-planned or in reaction to the movement of two testers (i.e., blocking exit gates). Players' acceleration was measured using an inertial measurement unit. Entropy was calculated from the acceleration signal and completion time was extracted using a magnet-based timing system. Significantly greater times and lower entropy (p<0.001) were found during agility runs to pre-planned COD runs. Furthermore, weak to moderate correlations were found between COD and agility for both completion time (r = 0.29, p<0.001) and entropy (r = 0.53, p<0.001, r2 = 28.1%). These results highlight that COD speed and agility are independent capacities and skills, and as such, should be tested and trained as distinct, separate qualities. Modifying task constraints including a reactive stimulus (i.e., cognitive factors), is essential for increasing task complexity by altering the biomechanical and coordinative aspects of the action.

What Tests are Used to Assess the Physical Qualities of Male, Adolescent Rugby League Players? A Systematic Review of Testing Protocols and Reported Data Across Adolescent Age Groups

BACKGROUND

Understanding the physical qualities of male, adolescent rugby league players across age groups is essential for practitioners to manage long-term player development. However, there are many testing options available to assess these qualities, and differences in tests and testing protocols can profoundly influence the data obtained.

OBJECTIVES

The aims of this systematic review were to: (1) identify the most frequently used tests to assess key physical qualities in male, adolescent rugby league players (12-19 years of age); (2) examine the testing protocols adopted in studies using these tests; and (3) synthesise the available data from studies using the most frequently used tests according to age group.

METHODS

A systematic search of five databases was conducted. For inclusion, studies were required to: (1) be original research that contained original data published in a peer-reviewed journal; (2) report data specifically for male, adolescent rugby league players; (3) report the age for the recruited participants to be between 12 and 19 years; (4) report data for any anthropometric quality and one other physical quality and identify the test(s) used to assess these qualities; and (5) be published in English with full-text availability. Weighted means and standard deviations were calculated for each physical quality for each age group arranged in 1-year intervals (i.e., 12, 13, 14, 15, 16, 17 and 18 years) across studies.

RESULTS

37 studies were included in this systematic review. The most frequently used tests to assess anthropometric qualities were body mass, standing height, and sum of four skinfold sites. The most frequently used tests to assess other physical qualities were the 10-m sprint (linear speed), 505 Agility Test (change-of-direction speed), Multistage Fitness Test (aerobic capacity), bench press and back squat one-repetition maximum tests (muscular strength), and medicine ball throw (muscular power). Weighted means calculated across studies generally demonstrated improvements in player qualities across subsequent age groups, except for skinfold thickness and aerobic capacity. However, weighted means could not be calculated for the countermovement jump.

CONCLUSION

Our review identifies the most frequently used tests, but highlights variability in the testing protocols adopted. If these tests are used in future practice, we provide recommended protocols in accordance with industry standards for most tests. Finally, we provide age-specific references for frequently used tests that were implemented with consistent protocols. Clinical Trial Registration This study was conducted in accordance with the Preferred Reporting Items of Systematic Review and Meta-analysis guidelines and was registered with PROSPERO (ID: CRD42021267795).

Development of a Cutting Technique Modification Training Program and Evaluation of its Effects on Movement Quality and Cutting Performance in Male Adolescent American Football Players

This study developed a cutting technique modification training program and investigated its effects on cutting performance and movement quality in adolescent American football players. For six weeks, an intervention group (IG) of 11 players participated in 25 min cutting technique modification training sessions integrated into team training twice a week, while a control group (CG) of 11 players continued their usual team training. Movement quality was assessed by evaluating 2D high-speed videos, obtained during preplanned 45° and 90° cutting tests, using the Cutting Movement Assessment Score (CMAS) qualitative screening tool. Cutting performance was assessed based on change of direction deficit (CODD). Significant interaction effects of time × group were found for CMAS in 45° and 90° cuttings (p < 0.001, ηp2 = 0.76, p < 0.001, ηp2 = 0.64, respectively), with large improvements in the IG (p < 0.001, g = -2.16, p < 0.001, g = -1.78, respectively) and deteriorations in the CG for 45° cuttings (p = 0.002, g = 1.15). However, no statistically significant differences in CODD were observed pre-to-post intervention. The cutting technique modification training was effective at improving movement quality without impairing cutting performance, and it can be used by practitioners working with adolescent athletes.

Acute effects of prior conditioning activity on change of direction performance. A systematic review and meta-analysis

We performed a systematic review and meta-analysis on the acute effects of prior conditioning activity (CA) on change of direction (COD) performance. Eligible studies, involving healthy participants undergoing acute CA with at least one measure of COD performance, were analysed across diverse databases. A total of 34 studies were included for systematic review with 19 studies included for the meta-analysis. The intervention condition resulted in significantly faster (Z = 4.39; standard mean difference [SMD] = 0.49; p < 0.05) COD performance compared with the control condition. Both unloaded and light loaded CA resulted in significantly greater (SMD = 0.58-0.59) COD performance compared to the control condition. Moreover, heavy loaded CA demonstrated a significant but small (SMD = 0.24) improvement in COD performance compared to the control condition. Age and study design had no effect on the overall meta-analysis outcomes. Both males and females exhibited similar moderate effects with CA but only males demonstrated significantly greater COD performance compared to control conditions. Our findings indicate that a range of CA protocols can acutely improve COD performance with unloaded and light-loaded CA resulting in the greatest performance enhancements. These findings will assist practitioners with the design and implementation of appropriate acute CA to improve COD performance.

Influence of physical fitness on decision-making of soccer referees throughout the match

The purpose of this study was to analyze the relationships between physical fitness and physical performance in competition and the decision-making (successes and errors). A sample of 22 male national-level soccer referees (weight: 72.7 kg; height: 178.0 cm; age: 23.4 years) participated in this study. Physical fitness was assessed through 6 series of 40 m (velocity) and Yo-yo (aerobic) test in annual exam by Soccer Committee, physical performance was performed through the total distance covered in competition (Experiment 1), and decision-making was registered through a simulated Video Assistant Referee system (VAR) with the consensus of 2 national referees evaluating only warnings (yellow cards), expulsions (red cards), established penalties and obvious goal actions (called and no called) (Experiments 2 and 3). Results showed that physical fitness test was related with total distance (rho = 0.63, p < .01) and success rate percentage (rho = 0.74, p < .05) registered during competition. The success rate percentage, in the first half, was observed 44% successes, and in the second half, 59% successes. The number of events called was related with the physical fitness test score (R2 = 0.71, p = .035; R2 = 0.64, p = .056, respectively). As conclusion, the main finding of this study has provided insight into decision-making behavior in real competitive matches and the physical fitness was the predictor of the successful decision-making being able to determine the permanency, promotion or decrease of category.

Clustering U-14 Portuguese regional team football players by lower limb strength, power, dynamic balance, speed and change of direction: understanding the field position factor

Objectives

The aim of this study was to cluster U-14 Portuguese regional team football players based on variables related to lower limb strength and power, dynamic balance, linear sprint, and change of direction.

Method

The sample consisted of 22 young male soccer players (13.83 ± 0.44 years). A set of variables related to lower limb strength and power, dynamic balance, linear sprint, and change of direction was measured.

Results

Overall, a non-significant field position was observed. The countermovement jump (p < 0.001, η² = 0.73), squat jump (p < 0.001), and 30 m linear sprint (p = 0.001) were the main variables responsible for establishing the clusters. Cluster 1 was characterized by a high slalom, i.e., it took longer to complete the test (speed and change of direction) and a low composite score in the dynamic balance. Cluster 2 was characterized by high squat jump, countermovement jump, and reactive strength ratio (lower limb strength and power). Cluster 3 was characterized by low squat jump and countermovement jump (lower limb strength and power), and a high 30 m sprint, i.e., it took longer to complete the test (speed and change of direction). Based on the results of the territorial map, the clusters consisted of: (i) cluster 1: two forwards, one midfielder, and five defenders; (ii) cluster 2: three forwards, two midfielders, and two defenders, and; (iii) cluster 3: four midfielders and three defenders.

Conclusions

Players from different field positions composed the three clusters. There was no cluster composed exclusively of players of the same field position. The development of individualized and specific enrichment training programs should consider a cluster analysis, as the positional effect can be overlooked.

Validity of the SKILLCOURT® technology for agility and cognitive performance assessment in healthy active adults

Background/Objectives

Agility and cognitive abilities are typically assessed separately by different motor and cognitive tests. While many agility tests lack a reactive decision-making component, cognitive assessments are still mainly based on computer-based or paper-pencil tests with low ecological validity. This study is the first to validate the novel SKILLCOURT technology as an integrated assessment tool for agility and cognitive-motor performance.

Methods

Thirty-two healthy adults performed agility (Star Run), reactive agility (Random Star Run) and cognitive-motor (executive function test, 1-back decision making) performance assessments on the SKILLCOURT. Cognitive-motor tests included lower limb responses in a standing position to increase the ecological validity when compared to computer-based tests. Test results were compared to established motor and agility tests (countermovement jump, 10 m linear sprint, T-agility tests) as well as computer-based cognitive assessments (choice-reaction, Go-NoGo, task switching, memory span). Correlation and multiple regression analyses quantified the relation between SKILLCOURT performance and motor and cognitive outcomes.

Results

Star Run and Random Star Run tests were best predicted by linear sprint (r = 0.68, p < 0.001) and T-agility performance (r = 0.77, p < 0.001), respectively. The executive function test performance was well explained by computer-based assessments on choice reaction speed and cognitive flexibility (r = 0.64, p < 0.001). The 1-back test on the SKILLCOURT revealed moderate but significant correlations with the computer-based assessments (r = 0.47, p = 0.007).

Conclusion

The results support the validity of the SKILLCOURT technology for agility and cognitive assessments in more ecologically valid cognitive-motor tasks. This technology provides a promising alternative to existing performance assessment tools.

Validity, Reliability, and Sensitivity of Mobile Applications to Assess Change of Direction Speed

This study aimed to assess the validity, reliability, and sensitivity of mobile applications for assessing change-of-direction speed (CODS) performance. Thirty college athletes performed two Illinois CODS tests during one session. Assessments were carried out simultaneously using six devices (the CODTimer app, Seconds Count app, StopwatchCamera app, two analog stopwatches, and timing gates). Validity analyses included Pearson's product-moment correlation analysis, a linear regression model, and Bland-Altman plots. Reliability analyses included the intraclass correlation coefficient (ICC), the coefficient of variation (CV%), and the paired-sample t test. Sensitivity analyses included the typical error and smallest worthwhile change (SWC). The results showed that validity, reliability, and sensitivity values were higher for the CODTimer app (r = 0.99, R2 = 0.99, mean bias = -0.03 ± 0.10, CV% = 3.21, ICC = 0.89, SWC rating: good, p = 0.84) and the Seconds Count app (r = 0.99, R2 = 0.99, mean bias = -0.03 ± 0.08, CV% = 3.28, ICC = 0.88, SWC rating: good, p = 0.84) relative to the StopwatchCamera app (r = 0.98, R2 = 0.97, mean bias = -0.11 ± 0.22, CV% = 3.43, ICC = 0.86, SWC rating: marginal, p = 0.10), Analog Stopwatch 1 (r = 0.98, R2 = 0.96, mean bias = -0.09 ± 0.42, CV% = 2.95, ICC = 0.90, SWC rating: good, p = 0.91), and Analog Stopwatch 2 (r = 0.99, R2 = 0.97, mean bias = -0.12 ± 0.88, CV% = 3.51, ICC = 0.87, SWC rating: marginal, p = 0.96). In conclusion, compared to timing gates, the CODTimer app and Seconds Count app provided lower measurement bias and higher sensitivity for assessing CODS performance.

Training for "Worst-Case" Scenarios in Sidestepping: Unifying Strength and Conditioning and Perception-Action Approaches

Sidesteps can impose high demands on the knee joint and lead to non-contact anterior cruciate ligament (ACL) injuries. Understanding how different constraints shape an athlete's movement strategy and the associated joint demands can help design training interventions to increase injury resilience. Motor capacities, such as muscular strength and power, act as boundaries for the safe execution of perceptual-motor skills and co-determine the emergence of unique movement strategies. Increasing single- and multi-joint strength enables a broader solution space for movement strategies and increases load tolerance. Manipulating task constraints during sidesteps can be used in the training process to systematically expose athletes to increasing demands (on the knee joint or any joint or structure) in preparation for "worst-case" scenarios. In particular, the type and timing of information available influence the preparation time, subsequently affecting the movement strategy and the associated magnitude of external knee joint loading (e.g., knee valgus moment). While an athlete's perceptual-cognitive skills contribute to the preparation time during in situ scenarios, attempts to further improve those skills with the aim of increasing athlete preparation time prior to "worst-case" scenarios are yet to demonstrate conclusive evidence of transfer to on-field situations. Therefore, in the current article, we reflect on the impact of different interacting constraints that influence the execution of sidesteps during in situ scenarios and impose high demands on the knee joint. Subsequently, we discuss how an integrated perspective, drawing on knowledge and perspectives from strength and conditioning and perception-action, may enhance an athlete's ability to withstand "worst-case" scenarios and adapt to perform varied movement executions when sidestepping.

Sex-Related Differences in Functional Fitness Outcomes in Older Adults

Sex-related differences in changes in functional fitness over time were longitudinally assessed in older adults participating in a group-based multimodal exercise program. From a database, functional fitness scores were obtained for 89 older adults (71.6 ± 6.5 years old) who had completed two assessments, 5-8 years apart. Lower body strength, upper body strength, aerobic endurance, flexibility, and change of direction performances were compared over time and with normative values. Females (p = .02), but not males, had an improvement in upper body strength over time. Females were also more flexible than males at both assessments (p ≤ .02). Of those who had five consecutive assessments, females were more flexible than males (p ≤ .05) and had a faster change of direction ability (p < .001). When compared with normative values, our results indicate that typical time-related functional fitness loss can be attenuated with group exercise. Our results further support the need to tailor exercise prescription according to the individual.

Effects of Arm Dominance and Decision Demands on Change of Direction Performance in Handball Players

This field study investigated the effect of unilateral dominance (handedness of players) on the change of direction speed in a specific cutting manoeuvre with a ball (in the direction of the throwing arm vs. against the direction of the throwing arm) in team handball. In addition, the effect of a cutting manoeuvre in response to an immediate stimulus compared to one planned in advance on the movement speed was analysed. Forty participants (22 male, 18 female, M_age 23 years) performed change of direction actions to the left and the right side (the direction of the throwing arm vs. against the direction of the throwing arm) under planned and reactive (light as visual stimuli) conditions. Change of direction speed was measured post-hoc by video-analyses. The results showed two effects. First, the decision demand in reaction to a visual stimulus reduced the speed in the change of direction compared to the planned action. Second, participants performed their action faster in the direction of the throwing arm than against it. The results replicate the effects of decision demands of previous studies and regardless of the reaction to the stimuli being unspecific, further studies could investigate if specific training can reduce the speed loss due to decision demands. The lateral speed differences of cutting manoeuvres of handball players have been analysed for the first time in this study. This effect could have several causes (e.g., coordination, power, motivation) which should be investigated in future studies in more detail.

Multimodal Agility-Based Exercise Training for Persons With Multiple Sclerosis: A New Framework

INTRODUCTION

Multimodal agility-based exercise training (MAT) has been described as a framework for fall prevention in the elderly but might also be a valuable concept for exercise training in persons with Multiple Sclerosis (pwMS).

THE PROBLEM

Current recommendations advise pwMS to perform a multitude of different exercise training activities, as each of these has its separate evidence. However, pwMS struggle even more than the general population to be physically active. Additionally, Multiple Sclerosis often leads to co-occurring mobility and cognitive dysfunctions, for which simultaneous, time-efficient, and engaging training approaches are still limited in clinical practice and healthcare.

THE SOLUTION

The MAT framework has been developed to integratively improve cardiovascular, neuromuscular, and cognitive function by combining aspects of perception and orientation, change of direction, as well as stop-and-go patterns (ie, agility), in a group-training format. For pwMS, the MAT framework is conceptualized to include 3 Components: standing balance, dynamic balance (including functional leg strength), and agility-based exercises. Within these Components sensory, cognitive, and cardiovascular challenges can be adapted to individual needs.

RECOMMENDATIONS

We recommend investigating multimodal exercise interventions that go beyond easily standardized, unimodal types of exercise (eg, aerobic or resistance exercise), which could allow for time-efficient training, targeting multiple frequent symptoms of persons with mild disability at once. MAT should be compared to unimodal approaches, regarding sensor-based gait outcomes, fatigue-related outcomes, cognition, as well as neuroprotective, and (supportive) disease-modifying effects.

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.

Reactive-Agility in Touch Plays an Important Role in Elite Playing Level: Reliability and Validity of a Newly Developed Repeated Up-and-Down Agility Test

Successful athletes are better at performing efficiently than the inferior in particular sports scenarios, while most existing performance tests in the field do not cover the sport-specific context fully. There were two purposes in this study: 1) to evaluate the reliability and validity of a novel Sector Reactive Agility Test (SRAT) which mimicked a reactive-agility defensive scenario in Touch, and 2) to determine the relationships between Touch players' agility and sprint performance. Twenty male Touch players from the elite division and another 20 from the amateur division were invited to participate in this study. They performed SRAT and a 20-m sprint test in two days. Excellent reliability and high precision were found in SRAT (intraclass correlation coefficient [ICC] = 0.97) and 20-m sprint test (ICC = 0.91). The time of completion in SRAT of the elite Touch players (23.93 s) was 2.95 s significantly shorter than that of the amateur players with a large effect size. Elite Touch players also demonstrated moderately faster (0.11 s) than the amateur Touch players in the 20-m sprint test. SRAT demonstrated high test-retest reliability and accuracy in measuring reactive-agility performance in Touch. The minimal detectable changes in SRAT and 20-m sprint test were 1.04 s and 0.13 s respectively. Furthermore, the speed of the 20-m sprint test and playing experience were associated with the time of completion of SRAT, explaining 56% of its variance (p &lt; 0.001). Other factors, such as cognition and the ability to control own central gravity, are deemed possible to influence Touch players' agility. Therefore, SRAT should be adopted in Touch player selection and training monitoring.

Reliability Study of a Functional Test for the Offensive Agility Performance in Water Polo

The aim of the study was to develop and assess the reliability of a functional agility test containing offensive elements for water polo players. Eighteen young male (15.3 ± 0.5 years, 178.3 ± 4.7 cm, 69.4 ± 10.0 kg) water polo players with a minimum of 5 years of sport-specific experience participated in this study. The test contained reactive high-intensity short-term swimming with changes in direction and manoeuvres after perceiving unknown stimuli given by tester players, and also included a shooting task at a goal, first from 7 m and then from 5 m. Execution time and shooting efficiency were measured by two experienced water polo coaches (Evaluators A and B). All statistical analyses were calculated using SPSS. The intrarater reliability between attempts showed good reliability for both evaluators (Evaluator A: ICC: 0.87; 95% CI: 0.66-0.95 and Evaluator B: ICC: 0.88; 95% CI: 0.68-0.96). Interrater reliability between Evaluators A and B was excellent at both attempts (Attempt 1: ICC: 0.97; 95% CI: 0.93-0.99 and Attempt 2: ICC: 0.98; 95% CI: 0.91-0.99). A lack of correlation between shooting performance from 7 m and 5 m distances and execution time was observed in the protocol. The test we presented in this study was found to be a reliable measurement tool for testing offensive agility performance based on open skill nature among water polo players.

Relationship between sprint, jump, dynamic balance with the change of direction on young soccer players' performance

The aim of the present paper was to determine the relationship between linear sprinting and jump performance, dynamic balance and change of direction on young soccer players. Ninety-four healthy young highly trained male soccer players belonging to the same high-performance academy agreed to participate in the study [twenty-seven soccer players U16 (14.8 ± 0.4 years; height: 170.6 ± 5.6 cm; body mass 64.7 ± 8.4 kg)] and [sixty-seven soccer players U19 (16.6 ± 1.3 years; height: 173.7 ± 7.2 cm; body mass 66.7 ± 8.0 kg)]. Participants completed 3 testing sessions, 7 days apart. Data from a CMJ, Crossover Hop Test, 10-m sprint test, 505 COD tests and the 90° COD test were collected. Moderate correlations were found in some of the cases (r values were between 0.2 and 0.5 in all cases, being p < 0.05), indicating that linear sprinting, jumping performance and dynamic balance are influential factors in agility but are not the main limiting factor. The highest correlation was found between the cross-over hop test and the 505 COD test (r = 0.44; p < 0.001). The main evidence from the current study suggested that linear sprinting, jumping performance and dynamics balance are determinants of COD, namely explaining the variations in such a skill. The current study revealed that short-distance sprint and jumping performance significantly explain the variations of COD performance on young soccer players.

Increased Cognitive Demands Affect Agility Performance in Female Athletes - Implications for Testing and Training of Agility in Team Ball Sports

Agility, a key component of team ball sports, describes an athlete´s ability to move fast in response to changing environments. While agility requires basic cognitive functions like processing speed, it also requires more complex cognitive processes like working memory and inhibition. Yet, most agility tests restrict an assessment of cognitive processes to simple reactive times that lack ecological validity. Our aim in this study was to assess agility performance by means of total time on two agility tests with matched motor demands but with both low and high cognitive demands. We tested 22 female team athletes on SpeedCourt, using a simple agility test (SAT) that measured only processing speed and a complex agility test (CAT) that required working memory and inhibition. We found excellent to good reliability for both our SAT (ICC = .79) and CAT (ICC =.70). Lower agility performance on the CAT was associated with increased agility total time and split times (p < .05). These results demonstrated that agility performance depends on the complexity of cognitive demands. There may be interference-effects between motor and cognitive performances, reducing speed when environmental information becomes more complex. Future studies should consider agility training models that implement complex cognitive stimuli to challenge athletes according to competitive demands. This will also allow scientists and practitioners to tailor tests to talent identification, performance development and injury rehabilitation.

Effect of Flywheel versus Traditional Resistance Training on Change of Direction Performance in Male Athletes: A Systematic Review with Meta-Analysis

Objective: This study aimed to systematically review and meta-analyze the effect of flywheel resistance training (FRT) versus traditional resistance training (TRT) on change of direction (CoD) performance in male athletes. Methods: Five databases were screened up to December 2021. Results: Seven studies were included. The results indicated a significantly larger effect of FRT compared with TRT (standardized mean difference [SMD] = 0.64). A within-group comparison indicated a significant large effect of FRT on CoD performance (SMD = 1.63). For TRT, a significant moderate effect was observed (SMD = 0.62). FRT of ≤2 sessions/week resulted in a significant large effect (SMD = 1.33), whereas no significant effect was noted for >2 sessions/week. Additionally, a significant large effect of ≤12 FRT sessions (SMD = 1.83) was observed, with no effect of >12 sessions. Regarding TRT, no significant effects of any of the training factors were detected (p > 0.05). Conclusions: FRT appears to be more effective than TRT in improving CoD performance in male athletes. Independently computed single training factor analyses for FRT indicated that ≤2 sessions/week resulted in a larger effect on CoD performance than >2 sessions/week. Additionally, a total of ≤12 FRT sessions induced a larger effect than >12 training sessions. Practitioners in sports, in which accelerative and decelerative actions occur in quick succession to change direction, should regularly implement FRT.

Determinants of Y-Shaped Agility Test in Basketball Players

Y-shaped agility test is a reactive agility test that includes both sensory and motor components. However, there is a lack of information about the contribution of these components to reactive agility in basketball players. Therefore, this study investigates: (i) the relationship between Y-shaped agility performance and reaction speed, sprint speed, change of direction speed, muscle strength, and (ii) determinants of this reactive agility test. Eleven male basketball players performed a Y-shaped agility test, 5 m and 20 m sprints, a 505 Agility test, squat, countermovement and drop jumps, and simple and two-choice reaction time tests. The results revealed a significant relationship between the time in Y-shaped agility test and 5 m sprint time (r = 0.795, p = 0.003, R2 = 0.632), 20 m sprint time (r = 0.676, p = 0.022, R2 = 0.457), and reactive strength index (r = −0.619, p = 0.042, R2 = 0.383), but not with simple and choice-based reaction times. These findings indicate that performance in the Y-shaped agility test is more profoundly determined by a motor rather than a sensory component. This may be ascribed to the structure of a predominantly velocity-oriented Y-shaped agility test with a small contribution of responses to visual stimuli. The adaptation of basketball players to training aimed at increasing speed and strength may also play a role. The structure of the Y-shaped agility test should be modified so as to better reflect the sensory component of reactive agility and more sensitively reveal within- and between-group differences.

Effects of Acute Fatigue on Cognitive Performance in Team Sport Players: Does It Change the Way They Perform? A Scoping Review

Fatigue caused by exercise or mentally demanding tasks can lead to an alteration in the cognitive functioning of athletes. Therefore, it is important to investigate whether and to what extent fatigue influences athletes cognitive performance in sports with high cognitive demands. This scoping review aims to map research articles dealing with the effects of acute fatigue on players cognitive performance in team sports. The main inclusion criterium was that studies had to examine the impact of any form of acute fatigue on (i) cognitive functions only, (ii) reactive agility, (iii) sport-specific skills with reactive components included. In total, 12 articles met our inclusion criteria. Results indicated that prolonged exercise causes a decline in the decision-making, attention, and perception abilities of players. Accuracy of sport-specific tasks with cognitive components included rather deteriorated after both exercise and mental fatigue inducement. However, alteration of players cognitive performance depends on the intensity and duration of fatigue-inducing tasks. Mental fatigue and consequent decision-making deterioration can be triggered by at least 30 min of a Stroop color-word task as well as smartphone application exposure. Analysis of the studies revealed a lack of research investigating the acute effect of fatigue on reactive agility, along with cognitive functions such as memory or learning. Due to possible acute negative effects of fatiguing exercise or mentally demanding tasks on human cognition, future research should consider the examination of different types and intensities of exercise on players’ cognitive performance.

The Mediating Effect of Change of Direction Speed in the Relationship between the Type of Sport and Reactive Agility in Elite Female Team-Sport Athletes

The main aim of this study was to examine the mediating effect of the change of direction speed (CODs) on reactive agility (RA) in female players participating in different team sports (TS). In total, there were 31 elite female players from the Polish national basketball (n = 12, aged 24.98 ± 3.38) and handball (n = 19, aged 27.34 ± 4.68) teams participated in this study. Two experiments using the 'five-time shuttle run to gates' test with similar movement patterns were used to determine the players' RA and CODs. A simple mediation model was utilised to investigate the potential mediation role of CODs and its effect on RA. The results revealed a primary, statistically significant effect of TS on RA (B = 0.796, p = 0.005), which decreased and became statistically insignificant after including the CODs variable into the model of mediation analysis (B = 0.337, p = 0.192). The RA test results were mediated by changes in CODs (B = 0.764, p < 0.001). Likewise, TS affected CODs (B = 0.602, p = 0.016). The general conclusion is that the relationship between TS and RA is not inherent. The direct effect of TS on RA disappears in the presence of the mediator CODs. Study results confirm the relevance of using the mediation analysis to apply in sport training. Identification of the critical ingredients of the athletes' agility performance can improve training programs by focusing on effective components.

Determinants of Reactive Agility in Tests with Different Demands on Sensory and Motor Components in Handball Players

This study investigates the relationship between reactive agility and reaction speed, sprint speed, and muscle strength and their contribution to Y-shaped agility test and reactive agility test (RAT) performance in handball players. Seven handball players performed a Y-shaped agility test and RAT, simple and choice-based reaction time test, reaction test to fast and slow generated visual stimuli, 5 m and 20 m sprint tests, a 505 Agility test, a squat jump, a countermovement jump, and a drop jump. The results reveal a significant relationship between the times for the Y-shaped agility test and the 20 m sprint (r = 0.777, p = 0.040, R = 0.604), as well as the time for the 505 Agility test (r = 0.770, p = 0.043, R2 = 0.593), and RSI (r = −0.755, p = 0.050, R2 = 0.570); however, no relationship was found with parameters pertaining to reaction speed. RAT performance did not significantly correlate with RSI, time in the 505 Agility test, squat jump height, time in the 20 m sprint, and reaction time to fast generated visual stimuli, although large effect sizes were found (r > 0.5). It seems that the contribution of sensory and motor components depends on the structure of the agility test. While the Y-shaped agility test is mainly determined by sprinting, the change of direction speed, and reactive strength, there is the tendency for the reactive agility test to be determined by strength, speed, and visual reaction time.

Agility testing in amateur soccer: A pilot study of selected physical and perceptual-cognitive contributions

The purpose of this study was to examine the relationships of physical and perceptual-cognitive factors with agility performance in amateur soccer players. Fifteen male amateur soccer players (age, 24.5 ± 1.9 years) completed a linear-sprint test with splits at 5 m, 10 m, and 30 m, a change-of-direction test of 12 m with 2 pre-planned directional changes of 45° at 2 m and 7 m, and a soccer-specific agility test with same movement pattern as the change-of-direction test but with the inclusion of a human stimulus performing passing movements. Additionally, the perceptual-cognitive deficit (agility performance minus change-of-direction performance) was calculated. In relation to agility performance, linear-sprint performance showed large relationships, which were higher with increasing sprint distance (5 m, r = 0.57; 10 m, r = 0.59; 30 m, r = 0.69), change-of-direction performance a very large relationship (r = 0.77), and the perceptual-cognitive deficit a large relationship (r = 0.55). The findings of this study highlight the relatively high contribution of both physical (i.e., linear-sprint and change-of-direction performance) and perceptual-cognitive factors (i.e., perceptual-cognitive deficit) in relation to soccer-specific agility performance at an amateur level. Consequently, such elements might be recommended to be included in training programs aimed at improving agility performance at this playing level. Moreover, the here introduced perceptual-cognitive deficit allows for a convenient and likewise thorough analysis of agility performance. Future studies should investigate the effects of both physically and perceptual-cognitive oriented training interventions on agility performance, which is considered a key element for success in soccer.

Nationwide Subjective and Objective Assessments of Potential Talent Predictors in Elite Youth Soccer: An Investigation of Prognostic Validity in a Prospective Study

Recent studies have provided empirical evidence on the prognostic relevance of objective performance diagnostics in the soccer talent identification and development process. However, little is known about the prognostic validity of coaches' subjective evaluations of performance. This study evaluated objective and subjective assessments within a nationwide talent development program and addressed motor, perceptual skill, and personality-related performance factors. Male players (N = 13,869; M_age = 12.59 ± 1.07 years) from the age groups U12 to U15 of the German soccer talent development program participated in this study. Participants completed an objective motor diagnostic (sprint, agility, dribbling, ball control, juggling) and were subjectively rated by their coaches (kicking skills, endurance, individual tactical skills, psychosocial skills). All nine predictors were assessed with sufficient psychometric properties (α ≥ 0.72; except dribbling and ball control: α ≥ 0.53). Players' success three seasons later was operationalized by achieving professional youth academy level or not (success rate, 9%). Independent-samples t-tests analyzed univariate mean group comparisons between future selected and non-selected players. Logistic regression models examined the multivariate prognostic validity of all assessments by predicting success with subjective (model 1), objective (model 2), and both groups of predictors (model 3). Confirming the univariate prognostic validity, future selected outperformed non-selected players regarding all predictors (each p < 0.001, except for agility in U15: p < 0.01). Tactical skills, kicking skills, and sprint were of highest predictive value (d ≥ 0.61 in each age group). Multivariate results provided empirical evidence for the subjective (7% ≤ Nagelkerke's R² ≤ 11%; each p < 0.001) and objective (8% ≤ Nagelkerke's R² ≤ 13%; each p < 0.001) assessments' prognostic validity. However, model 3 revealed the best statistical explanatory power in each age group (0.15 ≤ Nagelkerke's R² ≤ 0.20; p < 0.001). In this combined assessment model, sprint, tactical skills, and dribbling were found to be the most predictive variables. In conclusion, this study reinforces the call for multidimensional diagnostics integrating objective and subjective assessments. Future research is needed to address the demands for longitudinal analyses of subjective ratings, the integration of biological maturation, and empirical evidence for female soccer.