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1.
Decision-making is a key component of an umpire’s in-game performance, with each decision potentially having a direct impact on the result of the game. Additionally, umpires have to be physically fit to ensure they keep up with the gameplay. While research has identified the decision-making demands and running demands of umpires separately, few have explored the relationship between them. The aim of this investigation was to examine the relationship between physical exertion and decision-making performance of Australian football umpires at the sub-elite and junior levels. A total of 18 Australian football umpires (sub-elite, n = 10; junior n = 8) performed 10 × 300 m runs, with each repetition immediately followed by a video-based decision-making test, then 1 min of recovery. A Mann–Whitney U assessment indicated a significant difference between the sub-elite and junior level umpires for decision-making accuracy (U = 13.00, z = ?2.43, P = 0.016, r = ?0.5). However, there was no significant difference in response time (U = 28.00, z = ?1.07, P = 0.315, r = ?0.25). The sub-elite umpires completed the running efforts in significantly less time than the junior umpires (P < 0.05). Further, there was no significant correlation between decision-making performance and running times for either skill level (P > 0.05). This suggests decision-making performance may not be affected by physical exertion. Therefore, it may be suggested coaches of football umpires allocate more time to the decision-making development of their umpires instead of focusing largely on the physical fitness side, as is currently the trend.  相似文献   

2.
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   

3.
Existing methods for developing decision–making skill for Australian football umpires separate the physical and perceptual aspects of their performance. This study aimed to determine the efficacy of incorporating video-based decision-making training during high-intensity interval training sessions, specific for Australian football umpires. 20 amateur Australian football umpires volunteered to participate in a randomised control trial. Participants completed an 8-week training intervention in a conditioning only (CON; n=7), combined video-based training and conditioning (COM; n=7), or separated conditioning and video-based training (SEP; n=6) group. Preliminary and post-testing involved a Yo-Yo Intermittent Recovery Test (Yo-YoIR1), and 10x300m run test with an Australian football specific video-based decision-making task. Overall, changes in decision-making accuracy following the intervention were unclear between groups. SEP was possibly beneficial compared to COM in Yo-YoIR1 performance, whereas CON was likely beneficial compared to COM in 10x300m sprint performance. There was no additional benefit to completing video-based training, whether combined with, or separate to physical training, suggesting that this was not an optimal training method. For video-based training to be an effective decision-making tool, detailed feedback should be incorporated into training. It is recommended that longer conditioning and video-based training interventions be implemented to determine training effectiveness.  相似文献   

4.
Abstract

The aim of the present study was to examine the effects of changes in the number of ball contacts allowed per individual possession on the physiological, technical, and physical demands within small-sided games in elite soccer. Twenty international players (age 27.4±1.5 years, body mass 79.2±4.2 kg, height 1.81±0.02 m, velocity at [Vdot]O2max 17.4±0.8 km ·h?1, percent body fat 12.7±1.2%) performed three different small-sided game formats (i.e. 2 vs. 2; 3 vs. 3; 4 vs. 4) on three different occasions in which the number of ball contacts authorized per possession was fixed (one touch, two touches, and free play). The relative pitch per player ratio was similar for all small-sided games. The small-sided games were performed with four support players (placed around the perimeter of pitch) with instructions to keep possession of the ball. The total duration of the small-sided games was the effective time of play. The physical demands, technical requirements, heart rates, post-exercise blood lactate concentrations, and ratings of perceived exertion (RPE) were assessed. The percentages of successful passes and numbers of duels were significantly lower when the small-sided game was played with one touch (P<0.001), whereas the number of balls lost increased (P<0.001 for 2 vs. 2 and 3 vs. 3; P<0.01 for 4 vs. 4). The small-sided game played with one touch also induced increases in blood lactate concentration and RPE, as well as greater physical demands in the total distance covered in sprinting and high-intensity runs. In conclusion, the main findings of this study are that by altering the number of ball contacts authorized per possession in small-sided games, the coach can manipulate both the physical and technical demands within such games.  相似文献   

5.
我国职业足球比赛裁判员现状与管理对策研究   总被引：5，自引：0，他引：5  
我国职业足球比赛裁判员的管理存在着足协权力过分集中，裁判员的职业道德素质重视不够，裁判选拔制度不够透明，管理法规执行不力，司法介入困难等问题。据此，从裁判员选拔制度、道德建设、监督部门的独立性、财产监察制度、舆论监督、司法介入、裁判的职业化进程及中国职业联盟组建等方面进行了对策性研究，为我国足球的进一步深化改革提供参考。  相似文献   

6.
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   

7.
Abstract

Pre-cooling studies report positive physiological and performance benefits in laboratory conditions, although research studies have not investigated these reported benefits in ecologically valid team-sport training and competition settings. Accordingly, this study investigated the effect of field-based pre-cooling strategies for professional football players during training and competition in the heat. Ten professional football players from an Australian A-League club performed two training sessions and competitive matches in hot ambient conditions (29±3oC, 78±8% relative humidity) with or without pre-cooling. The pre-cooling intervention involved 20-min of an ice-vest, cold towels and 350 mL ice-slushie drink. Training sessions (n=9) were randomised, and consisted of 2 x 10-min interval training, followed by 6 x 3-min of 5v5 small sided games. Competitions (n=7) involved official A-League matches during the 2009–10 season. Player movement characteristics, core temperature (gastrointestinal), skin temperature, nude mass, heart rate, capillary blood (glucose, K+, Na+, haematocrit), perceptual exertion and thermal stress measures were recorded. No significant differences (P>0.05) were present between conditions for any measure of physical performance, although moderate-large effects for a greater total and relative distance covered during training were present (d > 0.8). While mean skin temperature was reduced following cooling, core temperature was only lower until following the warm-up in training and was even less evident during matches (P>0.05; d < 0.6). However, a smaller change in mass (sweat loss) and reduced perceptual exertion and thermal stress were evident during training following cooling (d > 0.9), although again, to a much lesser extent in matches (d = 0.6). In conclusion, equivocal findings were present for the effects of pre-cooling for professional football players during competitive training and matches in the heat. However, performance and thermoregulatory response trends showed similarities to previous laboratory evidence. The field-based nature of the current study may highlight that the transfer of lab findings to field settings is difficult or the strength of the intervention is diminished by the settings.  相似文献   

8.
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   

9.
Abstract

Children normally lack the strength and physical characteristics required to use the equipment and rules of adult sports. Studies that utilise a test have shown that changes in the ball mass may improve shot performance and other ball handling skills. The objective of this study was to analyse with which ball participants played a higher number of one-on-one situations in basketball. The participants were 54 nine to eleven-year-old boys from six teams. We established three situations in which the participants played four games with each of the following balls: (a) regulation ball (485 g, 69–71 cm), (b) ball of smaller mass (440 g, 69–71 cm), and (c) ball of greater mass (540 g, 69–71 cm). The procedures that were followed were: (a) defining the variable, the dependent variable was the number of one-on-one situations; (b) instructing the observers and obtaining reliability, reliability was above 0.95; (c) monitoring the properties of the ball and filming the games; and (d) recording (four observers) the data from the observation of the game videos. The results reflected statistically significant differences for the number of one-on-one situations χ 2 (2, N=1,858)=44.510, P=0.000, indicating an increase when using the 440 g ball in comparison to the regulation ball, the 540 g ball, and the results of the reviewed studies.  相似文献   

10.
This study investigated the associations between fundamental athletic movement and physical fitness in junior Australian football (AF). Forty-four under 18 players performed a fundamental athletic movement assessment consisting of an overhead squat, double lunge, single leg Romanian deadlift and a push up. Movements were scored on three assessment criterions using a three-point scale. Additionally, participants performed five physical fitness tests commonly used for talent identification in AF. A Spearman’s nonparametric correlation matrix was built, with correlation coefficients being visualised using a circularly rendered correlogram. Score on the overhead squat was moderately positively associated with dynamic vertical jump height on left (rs = 0.40; P ≤ 0.05) and right (rs = 0.30; P ≤ 0.05) leg take-off, stationary vertical jump (rs = 0.32; P ≤ 0.05) and negatively associated with 20-m sprint time (rs = ?0.35; P ≤ 0.05). Score on the double lunge (left/right side) was moderately positively associated with the same physical fitness tests as well as score on the multistage fitness test. Results suggest that improvements in physical fitness qualities may occur through concurrent increases in fundamental athletic movement skill, namely the overhead squat and double lunge movements. These findings may assist with the identification and development of talent.  相似文献   

11.
It seems that dehydration may impair decision-making performance in athletes. Purpose: This study aimed to investigate the influence of dehydration on passing decision-making performance in soccer players. Method: Participants were 40 male soccer players (Mage = 22.3 ± 2.3 years) who agreed to participate in the study and were randomly assigned to the following conditions: control (CON), dehydration (DEH), and euhydration (EUH). The players played in 2 games of 90 min in duration (2 45-min halves) followed by 2 15-min halves (overtime) with and without proper hydration. The Game Performance Assessment Instrument (GPAI) was considered for the analysis of passing decision making. Results: The GPAI analysis indicated effective reduction in the decision-making index in the DEH condition compared with the EUH and CON conditions, F(2, 38) = 31.4, p < .05, ES = 0.8. Conclusions: In conclusion, dehydration may be considered a mediating factor in the passing decision-making performance of male soccer athletes.  相似文献   

12.
Abstract

The purpose of this study was to determine the effects of training change-of-direction speed and small-sided games on performance in the Planned-AFL agility test and reactive agility. Twenty-five elite-standard U-18 Australian Rules football players were randomly allocated either to a change-of-direction group or a small-sided games group. Players participated in one or two 15-min sessions per week with 11 sessions conducted over a 7-week period during the season. Tests conducted immediately before and after the training period included the Planned-AFL agility test and a video-based reactive agility test specific to Australian Rules football. The reactive agility test variables were total time, decision time and movement response time. The small-sided games group improved total time (P = 0.008, effect size = 0.93), which was entirely attributable to a very large reduction in decision time (P < 0.001, effect size = 2.32). Small-sided games produced a trivial change in movement response time as well as in the Planned-AFL agility test (P > 0.05). The change-of-direction training produced small to trivial changes in all of the test variables (P > 0.05, effect size = 0–0.2). The results suggest that small-sided games improve agility performance by enhancing the speed of decision-making rather than movement speed. The change-of-direction training was not effective for developing either change-of-direction speed as measured by the Planned-AFL test or reactive agility.  相似文献   

13.
To determine the movement patterns and physiological demands of top-class soccer assistant referees, we performed computerized time-motion analysis and measured heart rate and blood lactate concentration in 15 assistant referees during 22 competitive matches in the top Danish league. To relate match performance to the physical capability of the assistant referees, they performed a 3 2 30 m sprint protocol before and after matches and a laboratory treadmill test within 3 weeks of the games. The mean total distance covered by the top-class assistant referees was 7.28 (range 5.78-8.16) km, of which 1.15 (0.86-1.44) km was high-intensity running and 1.16 (0.12-2.34) km was sideways running. The amount of high-intensity running during a game was correlated with performance of repeated sprints (r = 0.80, P ? 0.05). Mean heart rate was 137 (117-159) beats · min-1 , corresponding to 73% (60-88%) of maximal heart rate and 65% (53-80%) of maximal oxygen uptake. Blood lactate concentration was 4.7 (1.6-11.0) and 4.8 (1.1-13.7) mmol · l -1 after the first and second half, respectively. Sprinting performance was poorer (P ? 0.05) after than before the games. The peak distance to the offside line was greater (P ? 0.05) in the second than the first half (7 - 1 vs 5 - 0 m). Our results show that: (1) top-class assistant soccer refereeing is characterized by brief intense bouts of forward and sideways running interspersed with long periods of low activity; (2) top-class soccer assistant referees have moderate aerobic energy production during games with episodes of high aerobic and anaerobic energy turnover; (3) assistant referees' performance of repeated sprints correlates with the amount of high-intensity running performed in a game; and (4) sprint performance decreases towards the end of a game, which appears to affect assistant referees' ability to keep up with play.  相似文献   

14.
Limited information exists about the movement patterns of field-hockey players, especially during elite competition. Time–motion analysis was used to document the movement patterns during an international field-hockey game. In addition, the movement patterns of repeated-sprint activity were investigated, as repeated-sprint ability is considered to be an important fitness component of team-sport performance. Fourteen members of the Australian men's field-hockey team (age 26±3 years, body mass 76.7±5.6?kg, [Vdot]O2max 57.9±3.6?ml?·?kg?1?·?min?1; mean±s) were filmed during an international game and their movement patterns were analysed. The majority of the total player game time was spent in the low-intensity motions of walking, jogging and standing (46.5±8.1, 40.5±7.0 and 7.4±0.9%, respectively). In comparison, the proportions of time spent in striding and sprinting were 4.1±1.1 and 1.5±0.6%, respectively. Our criteria for ‘repeated-sprint’ activity (defined as a minimum of three sprints, with mean recovery duration between sprints of less than 21?s) was met on 17 occasions during the game (total for all players), with a mean 4±1 sprints per bout. On average, 95% of the recovery during the repeated-sprint bouts was of an active nature. In summary, the results suggest that the motion activities of an elite field-hockey competition are similar to those of elite soccer, rugby and Australian Rules football. In addition, the investigation of repeated-sprint activity during competition has provided additional information about the unique physiological demands of elite field-hockey performance.  相似文献   

15.
Abstract

The aim of this study was to examine the effects of exercise type, field dimensions, and coach encouragement on the intensity and reproducibility of small-sided games. Data were collected on 20 amateur soccer players (body mass 73.1 ± 8.6 kg, stature 1.79 ± 0.05 m, age 24.5 ± 4.1 years, [Vdot]O2max 56.3 ± 4.8 ml · kg?1 · min?1). Aerobic interval training was performed during three-, four-, five- and six-a-side games on three differently sized pitches, with and without coach encouragement. Heart rate, rating of perceived exertion (RPE) on the CR10-scale, and blood lactate concentration were measured. Main effects were found for exercise type, field dimensions, and coach encouragement (P < 0.05), but there were no interactions between any of the variables (P > 0.15). During a six-a-side game on a small pitch without coach encouragement, exercise intensity was 84 ± 5% of maximal heart rate, blood lactate concentration was 3.4 ± 1.0 mmol · l?1, and the RPE was 4.8. During a three-a-side game on a larger pitch with coach encouragement, exercise intensity was 91 ± 2% of maximal heart rate, blood lactate concentration was 6.5 ± 1.5 mmol · l?1, and the RPE was 7.2. Typical error expressed as a coefficient of variation ranged from 2.0 to 5.4% for percent maximal heart rate, from 10.4 to 43.7% for blood lactate concentration, and from 5.5 to 31.9% for RPE. The results demonstrate that exercise intensity during small-sided soccer games can be manipulated by varying the exercise type, the field dimensions, and whether there is any coach encouragement. By using different combinations of these factors, coaches can modulate exercise intensity within the high-intensity zone and control the aerobic training stimulus.  相似文献   

16.
This study evaluated whether exposing junior netball players to greater amounts of competition relevant activity (playing form activity) had an effect on game play outcomes and session involvement. A group-randomised controlled trial in one junior netball club in the Hunter Region, NSW, Australia. Ninety female athletes (mean age = 9.04 years, SD 1.53) were randomised by team (n = 11) into the intervention (n = 41) or 9-week wait-list control (n = 49) condition. The Professional Learning for Understanding Games Education into Sport (PLUNGE into Sport) programme was undertaken in the first half of nine training sessions (9 × 30 min). The intervention exposed athletes to playing form activity through a coach development programme within training sessions. Athletes’ decision-making, support and skill outcomes during a small-sided invasion game, and session involvement (pedometer step/min), were measured at baseline and 9-week follow-up. Linear mixed models revealed significant group-by-time intervention effects (P < 0.05) for decision-making (d = 0.4) and support (d = 0.5) during game play, and in-session activity (d = 1.2). An intervention exposing athletes to greater levels of playing form activity, delivered via a coach education programme, was efficacious in improving athlete decision-making and support skills in game play and increasing athlete involvement during sessions.  相似文献   

17.
Abstract

The aim of this study was to establish the net energy cost of dribbling a soccer ball. Eight male footballers ran for 5 min on a treadmill at speeds of 9, 10.5, 12 and 13.5km ·h –1 while dribbling a football against a rebound box; running at each of these speeds without the ball constituted controls. Oxygen uptake ([Vdot]O 2 ), perceived exertion (RPE) and blood lactate levels were measured and compared between the two conditions. The energy expended increased linearly with speed for both exercise modes, the mean increment of 1.24 kcal·min –1 caused by dribbling being independent of the speed of motion. Individual differences in efficiency of dribbling could not be explained by considering different patterns of stride characteristics. Similarly, RPE showed a constant elevation for dribbling over running at each speed, and a linear increase with speed of motion for both modes. Blood lactate increased disproportionately with speed for dribbling, onset of metabolic acidosis being attained at a lower speed for the experimental task. It was concluded that dribbling a ball does significantly increase the energy cost and perceived exertion of motion, as well as inducing disproportionate rises in blood lactate when performed at high speeds.  相似文献   

18.
Abstract

The aim of this study was to determine whether an exogenous sodium lactate infusion increases blood lactate concentration and decreases performance during a 20-km time-trial. Highly trained male cyclists performed a 20-km time-trial with a saline (control) or sodium lactate infusion. Sodium lactate was infused at rates previously observed to raise blood lactate concentration by 2 mmol·l?1 in trained individuals cycling at 65% of maximum oxygen uptake. Blood lactate concentration increased (P≤0.0001) during both the control and sodium lactate trials compared with rest, with peak values of 9.6 and 10.6 mmol·l?1, respectively. The increase in sodium lactate over time was not significantly different from the control (P=0.34). Time to complete the time-trial and average power for the time-trial were not significantly different between the control (25.72±0.80 min; 348.0±32.4 W) and sodium lactate trials (25.58±0.93 min; 352.6±39.3 W). In addition, rating of perceived exertion, heart rate, and respiratory parameters did not differ between trials. In conclusion, when exogenous lactate is infused during a 20-km cycling time-trial, an exercise bout performed above the maximal lactate steady state, blood lactate concentration did not increase. Furthermore, exogenous lactate infusion did not decrease exercise performance, increase perceived exertion, or change respiratory parameters. Because lactate per se did not change performance outcomes or measured perceived exertion, we suggest that alternative objective measures of exercise intensity and performance be explored.  相似文献   

19.
Abstract

In this study, we investigated the physical demands and activity profiles of international field hockey umpires during match-play. We collected GPS data and heart rates from ten umpires over 16 international matches. Total mean distance covered in a full match was 6655±406 m. No differences were observed between mean distances covered in the first and second halves (3390±241 m and 3264±253 m respectively; P =0.093). Hockey umpires spent 2.7±1% of the total match time performing high-intensity running (>15.5 km · h–1). Paired t-tests revealed no difference in the distance umpires covered during high-intensity running in the first versus the second half (339±168 m vs. 285±106 m; P=0.113), or in the number of sprints performed (3.4±2.3 vs. 2.8±2.1; P=0.290). There was large inter-individual variability in the total distance covered at high intensity (range 274–999 m). No difference in mean heart rates was evident between the first and second half (150±9 and 147±10 beats · min–1 respectively; P =0.055). The results of this study show that the performance of the participating hockey umpires did not decrease from the first to the second half. Training and testing procedures should be updated to reflect the specific role of the hockey umpire.  相似文献   

20.
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   

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