首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献，搜索用时 23 毫秒
1.
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   

2.
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   

3.
This study investigated the influence of match phase and field position on collective team behaviour in Australian Rules football (AF). Data from professional male athletes (years 24.4 ± 3.7; cm 185.9 ± 7.1; kg 85.4 ± 7.1), were collected via 10 Hz global positioning system (GPS) during a competitive AFL match. Five spatiotemporal metrics (x-axis centroid, y–axis centroid, length, width, and surface area), occupancy maps, and Shannon Entropy (ShannEn) were analysed by match phase (offensive, defensive, and contested) and field position (defensive 50, defensive midfield, forward midfield, and forward 50). A multivariate analysis of variance (MANOVA) revealed that field position had a greater influence on the x-axis centroid comparative to match phase. Conversely, match phase had a greater influence on length, width, and surface area comparative to field position. Occupancy maps revealed that players repositioned behind centre when the ball was in their defensive half and moved forward of centre when the ball was in their forward half. Shannon Entropy revealed that player movement was more variable during offence and defence (ShannEn = 0.82–0.93) compared to contest (ShannEn = 0.68–0.79). Spatiotemporal metrics, occupancy maps, and Shannon Entropy may assist in understanding the game style of AF teams.  相似文献   

4.
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   

5.
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   

6.
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   

7.
The aim of the current study was to investigate positional specific physical performance and external load responses to short term fixture congestion in English professional soccer. A total of 515 match observations were categorised as G1: the first game in a week with >4 days following a previous game, G2: the second game in a week played <4 days since G1, and G3: the third game in a week played with <4 days between each of the previous games. Global positioning system and accelerometer-based metrics were partitioned into fifteen-minute epochs. These data were then analysed using a linear mixed model to assess both the within and between game positional differences. Total, low-intensity (<4.0 m·s?1), medium-intensity (MID; 4.0–5.5 m·s?1), and sprint distance (>7.0 m·s?1) were significantly different across games. No between game positional differences were identified; however, within match position specific differences were observed for measures of MID and HID. No significant differences were evident for accelerometer derived metrics between games or across positions. The current data suggests that the use of fifteen minute within game epochs enables the detection of alterations in physical output during congested schedules. The observed within game positional differences has implications for player specific conditioning and squad rotation strategies.  相似文献   

8.
Applying an established theory of cognitive development―Skill Theory―the current study compares the game-reading skills of youth players selected for a soccer school of a professional soccer club (n = 49) and their non-selected peers (n = 38). Participants described the actions taking place in videos of soccer game plays, and their verbalisations were coded using Skill Theory. Compared to the non-selected players, the selected players generally demonstrated higher levels of complexity in their game-reading, and structured the information of game elements―primarily the player, teammate and field―at higher complexity levels. These results demonstrate how Skill Theory can be used to assess, and distinguish game-reading of youth players with different expertise, a skill important for soccer, but also for other sports.  相似文献   

9.
The relative age effect (RAE) is a well-established phenomenon in education and sports. Coaches have been assumed to be important social agents of RAE via biased selection decisions in favour of children with maturation advantages. In the present research, we used the Implicit Association Test to investigate automatic associations between body size and a player’s domain-specific giftedness amongst youth baseball (N = 18) and youth soccer coaches (N = 34). We found medium to strong automatic associations between body size and player giftedness (baseball: MD = 0.62; soccer: MD = 0.51). Specifically, taller players were associated with positive performance-related attributes, whereas smaller players were associated with negative attributes. The results are in line with theories of grounded cognition by showing that the abstract concept of “sport giftedness” is partly grounded in the perception of physical height amongst youth sports coaches. We argue that this grounded cognition has the potential to influence coaches’ selection decisions and in turn account for RAE as coaches are biased towards physically more matured players, even when no apparent performance advantage is evident.  相似文献   

10.
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   

11.
The coaching competency research has demonstrated the role of coaching efficacy and coaching behaviors on various athlete outcomes. However, athlete perceptions of these relationships and how they affect performance are less understood. Purpose: This study examined if coaching efficacy is predictive of player perceptions of coaches’ leadership styles, team atmosphere, and team performance in a soccer season. Method: Fifteen male premier league soccer coaches (Mage = 45.27, SD = 6.07) and 226 players (Mage = 25.66, SD = 3.96) from Botswana participated in the study. All participants completed a background information questionnaire. Coaches completed the Coaching Efficacy Scale. Players rated their coaches’ leadership styles using the Revised Leadership Scale for Sports as well as team atmosphere. Team performance was based on position in the league log and player ratings of the teams’ performance. Results: Findings showed that coaches’ self-ratings on technique efficacy predicted player perceptions of the coaches’ use of all six leadership styles. Game strategy efficacy predicted higher team atmosphere and team performance. Motivation efficacy was not significantly associated with player perceptions of the coaches’ use of any of the leadership styles, while character building efficacy was negatively associated with the various leadership styles. Conclusion: Findings provide support to previous research evidence linking higher coaching efficacy, leadership styles, and team outcomes. The study expands the emergent research within the coaching competency literature that examines player perceptions of coaches’ behaviors and leadership styles.  相似文献   

12.
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   

13.
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   

14.
Numerous skill batteries assess fundamental motor skill (e.g., kick, hop) competence. Few skill batteries examine lifelong physical activity skill competence (e.g., resistance training). This study aimed to develop and assess the content validity, test-retest and inter-rater reliability of the “Lifelong Physical Activity Skills Battery”. Development of the skill battery occurred in three stages: i) systematic reviews of lifelong physical activity participation rates and existing motor skill assessment tools, ii) practitioner consultation and iii) research expert consultation. The final battery included eight skills: grapevine, golf swing, jog, push-up, squat, tennis forehand, upward dog and warrior I. Adolescents (28 boys, 29 girls; M = 15.8 years, SD = 0.4 years) completed the Lifelong Physical Activity Skills Battery on two occasions two weeks apart. The skill battery was highly reliable (ICC = 0.84, 95% CI = 0.72–0.90) with individual skill reliability scores ranging from moderate (warrior I; ICC = 0.56) to high (tennis forehand; ICC = 0.82). Typical error (4.0; 95% CI 3.4–5.0) and proportional bias (r = ?0.21, p = .323) were low. This study has provided preliminary evidence for the content validity and reliability of the Lifelong Physical Activity Skills Battery in an adolescent population.  相似文献   

15.
The functional asymmetry of the lower limbs has been regarded as a relevant factor of the performance of football players. We purposed to ascertain whether a specific technical training programme for the non-preferred foot has implications in the increasing utilisation rate of the respective member during the game. Young football players (n = 71) were randomly divided into experimental group (N = 35; 14.37 ± 1.94 years) and control group (N = 36; 14.50 ± 1.81 years). The study was developed into three stages: first, assessment of the index utilisation of both limbs during the game; second, application of a technical training programme that includes the drilling of specific motor skills exclusively directed to the non-preferred foot; and third, assessment of the new rate of both limbs’ utilisation after the predefined six months. The main findings were: (1) the use of the non-preferred foot increased significantly with the technical training programme in the experimental group and remained constant in the control group; (2) the use of the preferred foot decreased significantly in the experimental group and remained similar in control group. We concluded that a systematic and specific technical training for the non-preferred foot increases its use and reduces functional asymmetry in game situation, consequently improving the player’s performance.  相似文献   

16.
The aim of this study was to evaluate physiological and technical attributes of prepubertal soccer players during multiple small-sided games (SSGs), and determine if SSGs can act as a talent identification tool. Sixteen highly trained U10 soccer players participated and separated into two groups of eight. Each group played six small-sided (4 vs. 4) matches of 5-min duration. Each player was awarded total points for the match result and goals scored. A game technical scoring chart was used to rate each player’s performance during each game. Time-motion characteristics were measured using micromechanical devices. Total points had a very large significant relationship with game technical scoring chart (r = 0.758, P < 0.001). High-speed running distance had a significantly large correlation with game technical scoring chart (r = 0.547, P < 0.05). Total distance covered had a significant and moderate correlation with game technical scoring chart (r = 0.545, P < 0.05) and total points (r = 0.438, P < 0.05). The results demonstrated a large agreement between the highest-rated players and success in multiple SSGs, possibly due to higher-rated players covering larger distances in total and at high speed. Consequently, multiple SSG could be used to identify the more talented prepubertal soccer players.  相似文献   

17.
Abstract

This study investigated the relative importance of physiological, anthropometric, and skill qualities to team selection in professional rugby league. Eighty-six high performance rugby league players underwent measurements of anthropometric (height, body mass, sum of seven skinfolds), physiological (speed, change of direction speed, lower body muscular power, repeated-sprint ability, prolonged high-intensity intermittent running ability, and maximal aerobic power), technical skill (tackling proficiency, draw and pass proficiency), and perceptual skill (reactive agility, pattern recall, pattern prediction) qualities. A linear discriminant analysis was also conducted comparing those players successful in gaining selection into the professional National Rugby League team with those not selected to determine which, if any, of these qualities could predict selection. Players selected to play in the first National Rugby League game of the season were older, more experienced, leaner, had faster 10m and 40m sprint times, and superior vertical jump performances, maximal aerobic power, tackling proficiency and dual-task draw and pass ability than non-selected players. Skinfold thickness and dual-task draw and pass proficiency were the only variables that contributed significantly (P < 0.05) to the discriminant analysis of selected and non-selected players. These findings suggest that selected physiological, anthropometric, and skill qualities may influence team selection in professional rugby league.  相似文献   

18.
The aim of this study was to analyse qualification patterns in middle distance running and identify whether athletes adopt theoretically optimal tactics, or whether the will to win overrides these. The performances of 295 men and 258 women finalists in the Olympic and IAAF World Championship 800 m and 1500 m events from 1999 to 2017 were analysed across all three rounds of competition. Finishing position, time and ranking amongst all competitors were found for each athlete. Position in the final was correlated with finishing position in the heats and semi-finals (all P < 0.001), but not with finishing times in those rounds. Of the 57 champions, 40 won both their heat and semi-final, even though a lower automatic qualification position would have been sufficient, and only 18 achieved a season’s best time in the final. The will to win amongst the eventual champions (and other medallists) suggests predominantly ego oriented behaviour that is encouraged by a performance climate, and which did not appear to differ between men and women. Coaches and athletes are recommended to note that championship-specific physiological and psychological factors are important to develop in training and prior competition to improve both short- and long-term championship strategies.  相似文献   

19.
Abstract

This study aimed to compare specific technical and tactical indicators of the team and centre forward role of Euro League, and Italian Serie A1, Serie A2, and Serie B men's water polo club competitions. A notational analysis was performed on 21 water polo matches to evaluate the occurrence of technical and tactical team and centre forward indicators, highlighting differences among championships according to chi-square analyses. Differences emerged for Counterattack (P < 0.001) and Power-Play (P < 0.001) possessions, Even (P < 0.001; Euro League: 3 ± 1, Serie A1: 3 ± 2, Serie A2: 3 ± 2, Serie B: 6 ± 4) and Power-Play (P = 0.001) goals, and exclusions and penalties (P = 0.008) of the team during Even possessions. Relatively to the role analyses, effects emerged for perimeter players playing events (P = 0.049), as well as for centre forwards' goals (P = 0.007) and exclusions and penalties (P < 0.001; Euro League: 8 ± 1, Serie A1: 6 ± 2, Serie A2: 6 ± 2, Serie B: 3 ± 2) occurring at the end of Even possessions. Therefore, in Euro League, and Italian Serie A1 and Serie A2, teams perform a high occurrence of Power-Play possessions following up an exclusion, especially achieved by the centre forward during Even possessions, while, in Italian Serie B, goals were mostly scored during Even possessions, with a relevant contribution from the centre forward role.  相似文献   

20.
This study examined the skill involvements of three positional groups across a junior representative rugby league season. Data were collected from 45 rugby league players (mean ± SD; age = 16.5 ± 1.0 years) currently participating in the Harold Matthews and SG Ball Cup. Players were subdivided into hit-up forwards, adjustables and outside backs. The frequency (n · min?1) of offensive, defensive and overall involvements was coded for each group using a notation system and a practical coach skill analysis tool. Multivariate analysis of variance (MANOVA) revealed a significant effect of playing position on skill involvements (F = 9.06; P < 0.001; ES = 0.41). Hit-up forwards performed a significantly greater frequency of offensive (0.31 ± 0.10), defensive (0.42 ± 0.15) and overall involvements (0.74 ± 0.19) when compared to adjustables (0.20 ± 0.08, 0.28 ± 0.08 and 0.52 ± 0.15, respectively) and outside backs (0.20 ± 0.12, 0.11 ± 0.07 and ± 0.31 ± 0.17, respectively). Further, adjustables performed a significantly greater number of defensive (0.28 ± 0.08) and overall involvements (0.52 ± 0.15) when compared to outside backs (0.11 ± 0.07 and 0.31 ± 0.17, respectively). The findings of this study suggest that it is important to consider a junior player’s positional group when analysing their skill involvements. Information gained from this study could assist in the design of specific training methodologies for junior rugby league players in high-level talent development programmes.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号