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1.
ABSTRACT

This study investigated whether a multi-dimensional assessment could assist with talent identification in junior Australian football (AF). Participants were recruited from an elite under 18 (U18) AF competition and classified into two groups; talent identified (State U18 Academy representatives; n = 42; 17.6 ± 0.4 y) and non-talent identified (non-State U18 Academy representatives; n = 42; 17.4 ± 0.5 y). Both groups completed a multi-dimensional assessment, which consisted of physical (standing height, dynamic vertical jump height and 20 m multistage fitness test), technical (kicking and handballing tests) and perceptual-cognitive (video decision-making task) performance outcome tests. A multivariate analysis of variance tested the main effect of status on the test criterions, whilst a receiver operating characteristic curve assessed the discrimination provided from the full assessment. The talent identified players outperformed their non-talent identified peers in each test (P < 0.05). The receiver operating characteristic curve reflected near perfect discrimination (AUC = 95.4%), correctly classifying 95% and 86% of the talent identified and non-talent identified participants, respectively. When compared to single assessment approaches, this multi-dimensional assessment reflects a more comprehensive means of talent identification in AF. This study further highlights the importance of assessing multi-dimensional performance qualities when identifying talented team sports.  相似文献   

2.
This study examined whether skill tests were predictive of status in junior Australian football. Players were recruited from the 2013 under 18 (U18) West Australian Football League competition and classified into two groups: elite (state U18 squad representative; n = 25; 17.9 ± 0.5 years) and subelite (nonstate U18 squad representative; n = 25; 17.3 ± 0.6 years). Both groups completed the Australian football kicking (AFK) and Australian football handballing (AFHB) tests, assessing kicking accuracy/ball speed and handballing accuracy on dominant and nondominant sides. A multivariate analysis of variance (MANOVA) modelled the main effect of “status”, whilst logistic regression models were built for the predictive analysis using the same test parameters. Between-group differences were noted across all parameters, with the combination of kicking accuracy and ball speed on the dominant and nondominant sides being the best predictor of status for the AFK test (wi = 0.25, AUC = 89.4%) and the combination of accuracy on the dominant and nondominant sides being the best predictor of status for the AFHB test (wi = 0.80, AUC = 88.4%). The AFK and AFHB tests are predictive of status, suggesting that their use is warranted as a means of talent identification in junior Australian football.  相似文献   

3.
Abstract

We examined the influence of instructions on decision-making accuracy using video simulations of game-specific scenarios in Australian football. Skilled performers (average age of 23.4 ± 4.2 years) differing in experience (range 0 to 339 Australian Football League (AFL) matches) assumed the role of the key attacker and verbally indicated their kicking decision. Participants were randomly stratified into three groups: (1) LOOSE (n = 15) – instructed to “keep the ball away from the loose defender”; (2) TTF (n = 15) – instructed to “take the first option”; and (3) NI (control) (n = 16) – given no instructions. Gaze behaviour for a subset of participants (n = 20) was recorded. In the scenarios with an even number of attacking and defensive players, the decision-making accuracy of LOOSE was greater than TTF. This difference was most evident for lesser experienced performers, highlighting that lesser experienced performers are more affected by instructional foci than experienced performers. Gaze behaviour was not affected by instructional foci, but visual search rate was greater in scenarios of greater player number and complexity.  相似文献   

4.
This study determined if small-sided games could discriminate perceptual-cognitive-motor skill in Australian Rules Footballers. Higher skilled Western Australian Football League (WAFL) (n = 17) and lesser skilled Amateur (n = 23) players were recruited. Participants played three small-sided games of three minutes. Each disposal was scored for decision-making and motor skill execution, with these scores combined for a total score. Mann-Whitney U tests indicated significantly superior mean decision-making by higher skilled (Median = 2.90, Range = 0.30) over lesser skilled (Median = 2.80, Range = 0.73) (p = .012) players. Execution score was not significantly different between groups. Linear mixed model analysis found higher skilled players (M = 5.32, SD = 1.19) scored significantly higher than lower skilled players (M = 4.90, SD = 1.52) on total score (p = .009). Large effect sizes were found for decision-making and total score relative to games and position played in WAFL players. High agreement of scoring was observed for an elite (inter-rater) and a novice (intra-rater) coaches. Linear mixed model analysis indicated mean total scores of WAFL players significantly predicted disposal efficiency in match performance (p = .011). Small-sided games can be easily implemented to identify talented players and assess perceptual-cognitive-motor skill.  相似文献   

5.
This study compared the athletic movement skill between elite Under-18 (U18) Australian football (AF) and senior Australian Football League (AFL) players. The U18 sample (n = 13; 17.7 ± 0.6 years) were representatives of an elite talent development programme. The AFL players were classified accordingly; Group 1 (1–4 AFL seasons; n = 20; 21.2 ± 1.9 years) and Group 2 (>5 AFL seasons; n = 14; 26.3 ± 2.6 years). Participants performed an athletic movement skill assessment, inclusive of five foundational movements. Each movement was scored across three assessment points using a three-point scale. Total score for each movement (maximum of nine) and overall score (maximum of 63) were used as criteria. Multivariate analysis of variance (MANOVA) was used to test the effect of developmental group (three levels) on the criteria. Receiver operating curves were built to examine the discriminant capability of the overall score. A significant effect of developmental group was noted, with the U18 sample having a lower mean total score for four of the five movements. Overall scores of 49/63 and 50/63 discriminated the elite U18 sample from Group 1 and Group 2, respectively. U18 players may have less developed athletic movement skills when compared to their senior AFL counterparts.  相似文献   

6.
This study investigated the extent to which position in the Australian Football League (AFL) national draft is associated with individual game performance metrics. Physical/technical skill performance metrics were collated from all participants in the 2014 national under 18 (U18) championships (18 games) drafted into the AFL (n = 65; 17.8 ± 0.5 y); 232 observations. Players were subdivided into draft position (ranked 1–65) and then draft round (1–4). Here, earlier draft selection (i.e., closer to 1) reflects a more desirable player. Microtechnology and a commercial provider facilitated the quantification of individual game performance metrics (n = 16). Linear mixed models were fitted to data, modelling the extent to which draft position was associated with these metrics. Draft position in the first/second round was negatively associated with “contested possessions” and “contested marks”, respectively. Physical performance metrics were positively associated with draft position in these rounds. Correlations weakened for the third/fourth rounds. Contested possessions/marks were associated with an earlier draft selection. Physical performance metrics were associated with a later draft selection. Recruiters change the type of U18 player they draft as the selection pool reduces. juniors with contested skill appear prioritised.  相似文献   

7.
This study examined the association between individual and team characteristics and the probability of being offered a second contract in professional Australian Football. Contract status was obtained from the AFL for players who were drafted in the AFL National Draft between 1999 and 2013 (n = 999). Individual player characteristics were retrieved from the AFL while variables relating to performance were accessed online via Champion Data®. A binary logistic regression examined the influence of each characteristic on the probability of a professional Australian Football player receiving a second contract. Receiver operating characteristic (ROC) curves and the associated AUC were used to assess the discriminant ability of both a training (n = 938) and test data set (n = 61). The characteristics that influenced the probability of receiving a second contract included first year debut (pr 0.606), draft order (pr – 0.126), draft year (pr 0.059), games played (pr 1.848), team state (pr 0.458), rising star nomination (pr 1.553) and team ladder position (pr ?0.043) (χ2 (8) = 198.28, p < 0.001). The ROC curve demonstrated an AUC of 82.4% (training) and 76.0% (test). A combination of individual and team based characteristics are associated with early career progression in professional Australian Football.  相似文献   

8.
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9.
Identifying performance differences between juniors at different stages of a talent pathway may assist with the development of prospective talent. This study investigated the relationship between game-based performance indicators and developmental level in junior Australian football (AF). Players were categorised into 2 groups according to developmental level; U16 and U18. Physical and technical skill performance indicators were collated for all U16 (n = 200) and U18 (n = 244) participants of their respective 2014 national championships. Data were acquired from all 28 games (12 U16, 16 U18); resulting in 1360 player observations (568 U16, 792 U18). Microtechnology and a commercial provider facilitated the quantification of 15 performance indicators. Generalised estimating equations (GEEs) modelled the extent to which these performance indicators were associated with developmental level. The GEE model revealed that “contested marks” and “contested possessions” had the strongest association with the U16 level, while “total marks” and “clearances” had the strongest association with the U18 level. The remaining performance indicators were not developmentally discriminant. These results indicate that there are distinctive features of gameplay more associated with the U16 and U18 levels in AF. Coaches may wish to consider these results when constructing training drills designed to minimise developmental gaps.  相似文献   

10.
This study investigated the evolution of game-play manifested via team performance indicator characteristics in the Australian Football League (AFL) from the 2001 to 2015 seasons. The mean values for 18 performance indicators were collated for every AFL team over 15-seasons. A multivariate analysis was used to uncover temporal trends in the dataset. Compared to the 2004 season, the 2005 to 2010 seasons were characterised by large growth in the counts of handballs (d = 0.83; 90% CI = 0.22–1.43), disposals (d = 1.24; 90% CI = 0.59–1.87), uncontested possessions (d = 1.37; 90% CI = 0.71–2.01), clangers (d = 2.14; 90% CI = 1.39–2.86) and marks (d = 1.43; 90% CI = 0.76–2.07). Contrastingly, the effective disposal percentage declined rapidly during the same period. The number of inside 50 m counts remained stable throughout the 15-season period. The ordination plot of league-wide performance indicator characteristics illustrated a distinct cluster from the 2001 to 2004 seasons, an abrupt shift from the 2005 to 2009 seasons, and an emergent (re)stabilisation from the 2010 to 2015 seasons. The results demonstrate the synchronous league-wide evolution of game-play in the AFL from the 2001 to 2015 seasons. Amongst other constituents, this evolution likely reflects the introduction of modernised coaching strategies, rule changes and changing perceptions of rule interpretations.  相似文献   

11.
ABSTRACT

This study investigated the association between talent selection criteria, draft order and match performance in professional Australian Football players. Physical performance results from the Australian Football League (AFL) National Draft combine and non-performance based talent selection criteria were collated for all players drafted in the National Draft with selections 1–80 between 2003 and 2008 (n = 318). Match performance was assessed via the AFL Player Ranking metric that was provided by a commercial statistical provider (Champion Data Pty Ltd). A combination of stepwise multiple regression and linear mixed model analyses examined the influence of National Draft combine physical performance assessments and non-performance based talent selection criteria on draft order and future match performance. Earlier draft selection was associated with Under-18 all Australian team selection, height, Under-18 National Championship participation and indigenous status. The 20 m sprint and state of origin were associated with later draft selection. Under-18 all Australian team selection increased both Player Ranking/game and total Player Ranking. Under-18 all Australian team selection displays efficacy for selecting players with the potential for success.  相似文献   

12.
Abstract

This study examined the birth distribution for adolescent (i.e. <20 years) and mature age players (i.e. ≥20 years) selected in the Australian Football League (AFL) National Draft between 2001 and 2012. Birth-date information was accessed for all first time AFL national draftees and players were then classified as either adolescent (N = 736) or mature age (N = 70) draftees. Chi-squared analysis showed a clear bias in the birth distribution of adolescent draftees towards players born in the first part of the classification period for both quartile (P < 0.001) and half-year (P < 0.001) compared to the Australian national population. There was a reverse relative age effect (RAE) for mature age draftees, with a significant bias towards players born in the latter part of the selection period for both quartile (P = 0.047) and half-year (P = 0.028) compared to the Australian national population. The selection bias towards relatively older players in adolescent AFL draftees may be related to advanced physical and psychological maturity, and exposure to higher-level coaching compared to their younger counterparts. The reverse RAE in mature age draftees is a novel finding and supports the need for strategies to encourage continued participation pathways for talented Australian football players born later in the selection year.  相似文献   

13.
ABSTRACT

The current study aimed to describe the distribution of physical and technical performance during the different phases of play in professional Australian Football. The phases of play (offence, defence, contested play, umpire stoppages, set shots and goal resets) were manually coded from video footage for a single team competing in 18 matches in the Australian Football League. Measures of physical performance including total distance (m), average speed (m · min?1), low-speed running (LSR, <14.4 km h?1), high-speed running (HSR, >14.4 km h?1), accelerations (2.78 m · s?2) and decelerations (?2.78 m · s?2) were derived from each phase of play via global positioning system (GPS) devices. Technical skill data including tackles, handballs and kicks were obtained from a commercial statistics provider and derived from each phase of play. Linear mixed-effects models and effect sizes were used to assess and reflect the differences in physical and technical performance between the six phases of play. Activity and recovery cycles, defined as periods where the ball was in or out of play were also described using mean and 95% confidence intervals. The analysis showed that several similarities existed between offence and defence for physical performance metrics. Contested play involved the highest total distance, LSR, accelerations, decelerations and tackles compared to all other phases. Offence and defence involved the highest average speed and HSR running distances. Handballs and kicks were highest during offence, while tackles were highest during contested play, followed by defence. Activity and recovery cycles involved mean durations of ~110 and ~39 s and average speeds of ~160 and ~84 m · min?1, respectively. The integration of video, GPS and technical skill data can be used to investigate specific phases of Australian Football match-play and subsequently guide match analysis and training design.  相似文献   

14.
ABSTRACT

The study aim was to investigate ball movement patterns using network analysis techniques, to compare between successful and unsuccessful outcomes and teams in the Australian Football League (AFL). This analysis focused on possession chains starting from a kick-in (n = 1,720), drawn from all games played in the 2015 AFL Premiership season (18 teams, 206 games). Player interactions were quantified using four network metrics: cluster coefficient, degree centrality, network density, and entropy. Three-way ANOVA with Tukey post hoc and ω2 effect sizes were calculated to assess whether differences existed between kick-in outcomes, ladder brackets, and match outcomes for each network metric. No significant differences were observed between ladder brackets or match outcomes for any network metric. More successful kick-in chains were characterised by lower density (ω2 = 0.26, large effect; F(9, 1678) = 66.6, p < 0.00) and higher entropy (ω2 = 0.17, large effect; F(9, 1678) = 39.6, p < 0.00). This suggests that chains resulting in successful kick-in outcomes exhibited lower interconnectedness, with a high number of players involved, and lower predictability in ball movement patterns. These findings have practical value for coaches and performance analysts and support further applications of network analysis in Australian football.  相似文献   

15.
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16.
Abstract

This study determined the precision of pencil and fan beam dual-energy X-ray absorptiometry (DXA) devices for assessing body composition in professional Australian Football players. Thirty-six professional Australian Football players, in two groups (fan DXA, N = 22; pencil DXA, N = 25), underwent two consecutive DXA scans. A whole body phantom with known values for fat mass, bone mineral content and fat-free soft tissue mass was also used to validate each DXA device. Additionally, the criterion phantom was scanned 20 times by each DXA to assess reliability. Test–retest reliability of DXA anthropometric measures were derived from repeated fan and pencil DXA scans. Fat-free soft tissue mass and bone mineral content from both DXA units showed strong correlations with, and trivial differences to, the criterion phantom values. Fat mass from both DXA showed moderate correlations with criterion measures (pencil: r = 0.64; fan: r = 0.67) and moderate differences with the criterion value. The limits of agreement were similar for both fan beam DXA and pencil beam DXA (fan: fat-free soft tissue mass = ?1650 ± 179 g, fat mass = ?357 ± 316 g, bone mineral content = 289 ± 122 g; pencil: fat-free soft tissue mass = ?1701 ± 257 g, fat mass = ?359 ± 326 g, bone mineral content = 177 ± 117 g). DXA also showed excellent precision for bone mineral content (coefficient of variation (%CV) fan = 0.6%; pencil = 1.5%) and fat-free soft tissue mass (%CV fan = 0.3%; pencil = 0.5%) and acceptable reliability for fat measures (%CV fan: fat mass = 2.5%, percent body fat = 2.5%; pencil: fat mass = 5.9%, percent body fat = 5.7%). Both DXA provide precise measures of fat-free soft tissue mass and bone mineral content in lean Australian Football players. DXA-derived fat-free soft tissue mass and bone mineral content are suitable for assessing body composition in lean team sport athletes.  相似文献   

17.
The objective was to investigate the relationship between Catechol-O-methyltransferase (COMT) rs4680 and serotonin-transporter-linked polymorphic region (5-HTTLPR) genotypes with concussion history and personality traits. Rugby players (“all levels”: n = 303), from high schools (“junior”, n = 137), senior amateur, and professional teams (“senior”, n = 166), completed a self-reported concussion history questionnaire, Cloninger’s Tridimensional Personality Questionnaire, and donated a DNA sample. Participants were allocated into control (non-concussed, n = 140), case (all) (previous suspected or diagnosed concussions, n = 163), or case (diagnosed only) (previous diagnosed concussion, n = 140) groups. COMT rs4680 Val/Val genotypes were over-represented in controls in all levels (P = 0.013, OR:2.00, 95% CI:1.15–3.57) and in juniors (P = 0.003, OR:3.57, 95% CI:1.45–9.09). Junior Val/Val participants displayed increased “anticipatory worry” (P = 0.023). The 5-HTTLPR low expressing group was under-represented in controls when all levels were considered (P = 0.032; OR:2.02, 95% CI:1.05–3.90) and in juniors (P = 0.021; OR:3.36, 95% CI:1.16–9.72). Junior 5-HTTLPR low and intermediate expressing groups displayed decreased “harm avoidance” (P = 0.009), “anticipatory worry” (P = 0.041), and “fear of uncertainty” (P < 0.001). This study provides preliminary indications that personality associated genetic variants can influence concussion in rugby.  相似文献   

18.
Decision-making is a central component of the in-game performance of Australian football umpires; however, current umpire training focuses largely on physiological development with decision-making skills development conducted via explicit lecture-style meetings with limited practice devoted to making actual decisions. Therefore, this study investigated the efficacy of a video-based training programme, aimed to provide a greater amount of contextualised visual experiences without explicit instruction, to improve decision-making skills of umpires. Australian football umpires (n = 52) were recruited from metropolitan and regional Division 1 competitions. Participants were randomly assigned to an intervention or control group and classified according to previous umpire game experience (i.e., experienced; less experienced). The intervention group completed a 12-week video-based decision-making training programme, with decision-making performance assessed at pre-training, and 1-week retention and 3-week retention periods. The control group did not complete any video-based training. Results indicated a significant Group (intervention; Control) × Test interaction (F(1, 100) = 3.98; P = 0.02, partial ?2 = 0.074), with follow-up pairwise comparisons indicating significant within-group differences over time for the intervention group. In addition, decision-making performance of the less experienced umpires in the intervention group significantly improved (F(2, 40) = 5.03, P = 0.01, partial ?2 = 0.201). Thus, video-based training programmes may be a viable adjunct to current training programmes to hasten decision-making development, especially for less experienced umpires.  相似文献   

19.
Abstract

We tested hypotheses grounded in self-determination theory regarding athletes' cognitive appraisals and emotional reactions when returning to competition following a serious injury. Professional male athletes (N = 225) competing in the Australian Football League were presented with return-to-competition scenarios that varied with respect to: (1) degree of self-determination and (2) salience of re-injury concern. Significant MANOVA main effects were observed for the degree of self-determination on both primary appraisals and emotional responses as well as for the salience of re-injury concern on emotional response. Follow-up ANOVA polynomial trend analyses provided support for the hypothesized trends for greater self-determination in the return to sport to result in more positive appraisals and affect. Findings support self-determination theory contentions and research indicating the psychological benefits of increased self-determination.  相似文献   

20.
This study assessed whether decisions made by six qualified referees were consistent when watching the live 2016 televised Champions League Final. Referees were paired off into three separate rooms. Two referees watched the game with no supporters present. Two watched the game surrounded by Real Madrid supporters, and the remaining two watched the game surrounded by Athletic Madrid supporters. Referees were asked to decide whether each decision made by the on-field referee was either correct or incorrect. Results identified two types of refereeing inconsistency. The first type was a systematic tendency of the supporting crowds (both rooms) to influence the adjudicating referees to make fewer incorrect (disagree with the on-field referee) decisions (8 and 5) than referees in the “no supporters” room (19) (χ2 = 11.22 [df = 2], P = 0.004). The second type of inconsistency was the home advantage “bias”, where the surrounding crowd influenced the adjudicating referees to favour their team, by disagreeing with the decision made by the on-field referee (χ2 = 6.0 [df = 2], P = 0.0498). One explanation for these inconsistencies is that referees adopt a coping strategy of “avoidance”, i.e., when faced with difficult decisions, referees simply avoid making unpopular decisions by waving “play on”.  相似文献   

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