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1.
2.
The goal of this research was to identify parameters among the 12 indicators of situation-related efficiency that differentiated between the winning and defeated top quality teams which played in final tournaments of the European club championships from 1992 to 2000. The differences were confirmed by discriminant analysis, although the canonical correlation was here somewhat lower than in the previous similar research studies done on the so-called regular season games. The probable reason for the smaller differences obtained in the present study may be found in almost equal (high) quality of the teams competing in Final Fours. The highest discriminative power was obtained in the variable defensive rebounds, then in the variables field goal percentage and free throw percentage, whereas the variable assist had evidently smaller impact with regard to the referent studies. The obtained results suggested that the winning teams showed more of tactical discipline and responsibility in controlling inside positions for defensive rebounds, as well as in controlling play on offense and the ball until the required open shot chance, which considerably reduced game risks and resulted in a lower number of turnovers and in a higher shooting percentage. Such a type of decision-making in play require a high degree of reciprocal help of players on both defense and offense and a higher level of concentration and self-confidence when shooting field goals and free throws. The common denominator of the winning teams was a lower number of imbalanced states in their play (the organized style of play on defense and offense implied) and a higher level of collective outplaying the opponents with the controlled system of play, which enabled entire potential of the victorious teams to be expressed.  相似文献   

3.
The aim of this study was to describe in the way teams played for the last eight seasons (from 2011–12 to 2018–19) in the Spanish Football First Division (Spanish LaLiga Santander), taking into account team match performances (n = 5,518). Ten technical-tactical and physical variables grouped into five dimensions were used: final behaviour (shots and crosses), set piece (corners and fouls), match volume (passes), physical performance (total distance covered) and collective use of the space (team width, team length, team defence height and distance from the goalkeeper to their defence). The main results were that the number of passes and team width showed a stable trend as the seasons passed. Nevertheless, the number of shots, crosses and corners, total distance covered, team length and distance from the goalkeeper to their defence showed a descending trend. The main conclusion was that over the seasons studied, the Spanish LaLiga Santander teams were characterized by an indirect style of play that, being the usual in this league, presented some evolution. The trend in the evolution of the game is that defence is put before attack. The findings of the study may be of interest to professional football staff to know more about the particular way teams play in competition, as well as its evolution, so as to focus on the training process according to the trend that is taking place in the game.  相似文献   

4.
This study aimed to analyse the influence of different contextual factors (i.e., defensive style and game outcome) on basketball players’ external load during games-based drills using ultrawideband (UWB) technology. Fourteen male professional basketball players belonging to an elite reserve Spanish club (ACB) participated in this study. The games-based drills consisted of one bout of 10 min played 5vs5 in which players were instructed to use man-to-man defence (MMD) and/or zone defence (ZD). In addition, the final game outcome (i.e., winning or losing) of the game-based drill was registered. External load variables per minute were recorded: total distance covered, distance covered in different speed zones, distance covered while accelerating and decelerating, maximum speed, steps, jumps and player load. A two-way ANOVA with the Tukey post hoc test was used to assess the impact of defensive style and final game outcome and the interaction of both factors on the external load encountered by basketball players. No meaningful differences (unclear) were found in the external loads between playing with MMD and with ZD and between winning and losing teams except for greater distance at high-speed running (18.0–24.0 km·h-1) in winning teams (p < 0.05, ES = 0.68, moderate). A significant interaction between defensive style and final game outcome was found for high decelerations (> -2 m·s-2) (p = 0.041; ES = 0.70) and jumps (p = 0.037; ES = 0.68). These results could potentially help coaching staff in prescribing an appropriate workload during basketball-specific game-based drills, and ultimately enhance the match performance.  相似文献   

5.
The aim of the study was to identify motor structures in elite female volleyball players aged 14-17, and to assess the effect of these motor structures on their technical and situation efficiency. For this purpose, a battery of 12 motor tests as predictor variables, and a set of six technical elements and evaluation of performance quality as criterion variables were applied in a sample of 147 female volleyballers aged 14-15 and a sample of 50 female volleyballers aged 16-17. Analysis of variance between subgroups within the groups of volleyballers aged 14-15 and those aged 16-17 showed the results on all motor tests to improve with the increase in situation performance, which was especially pronounced in the tests assessing explosive strength and agility. The same held true for the results on all tests assessing volleyball techniques, spike and block in particular. In both samples, factor analysis of motor tests isolated two factors underlain by the generation and regulation of strength, and the mechanism of speed regulation. Canonical correlation analysis between the motor regulatory mechanisms and technical elements revealed determination of the mechanisms of strength and technical efficiency in both samples. Regression correlation analysis showed the mechanisms of strength regulation and speed to be good predictors of game performance in female volleyballers aged 14-15 and 16-17, whereby the mechanism of strength regulation had greater effect on the game performance than the mechanism of speed regulation. Regression correlation analysis also revealed the set of 6 techniques evaluated to be a good predictor of situation efficiency in both groups of female volleyballers aged 14-15 and 16-17. The block and spike techniques were found to be the best predictors of game performance quality in the former, and the techniques of spike and block in the latter. Based on the results obtained, a possible model of selection for supreme score achievement in female volleyball is described.  相似文献   

6.
The aim of the study was to identify differences in morphological variables and variables for quality assessment of volleyball techniques in young female volleyball players according to age and situation efficacy, and to estimate the effect of technique quality on situation efficacy. A set of 13 morphological measures and 6 technique elements were used in a sample of 246 female volleyball players divided into four age groups: 32 players aged 12-13, 147 players aged 14-15, 50 players aged 16-17, and 17 players aged 18-19. The quality of performance was assessed as a criterion variable. Analysis of variance showed the female volleyball players of various age groups to differ significantly according to the variables assessing the longitudinal skeleton dimensionality, and body mass and volume, as well as in all tests used on volleyball technique evaluation. Analysis of variance within particular age groups additionally clarified the process of modification in all study variables. Regression correlation analysis indicated the set of variables for the 6 evaluated techniques to be a rather good predictor of situation efficacy in all age groups, with service technique as the best predictor of performance quality in youngest players aged 12-13 and 14-15; spike and block techniques in players aged 16-17; and field defense technique in players aged 18-19.  相似文献   

7.
The primary aim of this study was to examine the effects of 6-week strength training with whole body vibration (WBV) on leg strength and jumping performance in volleyball and beach volleyball players. Twenty-three sub-elite male volleyball (VB; n=12) and beach volleyball players (BVB; n=11) aged 21.2±3.0 years were divided into two groups and subjected to 6 weeks of strength training (three one-hour sessions per week): (I) 12 players (6 VB and 6 BVB players) underwent training with WBV (30-40 Hz, 1.7-2.5 mm, 3.0-5.7 g), and (II) 11 players (6 VB and 5 BVB players) underwent traditional strength training. Squat jump (SJ) and countermovement squat jump (CMJ) measurements by the Ergo Tester contact platform and maximum leg press test (1RM) were conducted. Three-factor (2 time x 2 WBV use x 2 discipline) analysis of variance for SJ, CMJ and 1RM revealed a significant time main effect (p<0.001), a WBV use effect (p<0.001) and a discipline effect (p<0.001). Significantly greater improvements in the SJ (p<0.001) and CMJ (p<0.001) and in 1RM (p<0.001) were found in the WBV training groups than in traditional training groups. Significant 3-way interaction effects (training, WBV use, discipline kind) were also found for SJ, CMJ and 1RM (p=0.001, p<0.001, p=0.001, respectively). It can be concluded that implementation of 6-week WBV training in routine practice in volleyball and beach volleyball players increases leg strength more and leads to greater improvement in jump performance than traditional strength training, but greater improvements can be expected in beach volleyball players than in volleyball players.  相似文献   

8.
In competitive situations, individuals need to adjust their behavioral strategy dynamically in response to their opponent’s behavior. In the present study, we investigated the neural basis of how individuals adjust their strategy during a simple, competitive game of matching pennies. We used entropy as a behavioral index of randomness in decision-making, because maximizing randomness is thought to be an optimal strategy in the game, according to game theory. While undergoing functional magnetic resonance imaging (fMRI), subjects played matching pennies with either a human or computer opponent in each block, although in reality they played the game with the same computer algorithm under both conditions. The winning rate of each block was also manipulated. Both the opponent (human or computer), and the winning rate, independently affected subjects’ block-wise entropy during the game. The fMRI results revealed that activity in the bilateral anterior insula was positively correlated with subjects’ (not opponent’s) behavioral entropy during the game, which indicates that during an interpersonal competitive game, the anterior insula tracked how uncertain subjects’ behavior was, rather than how uncertain subjects felt their opponent''s behavior was. Our results suggest that intuitive or automatic processes based on somatic markers may be a key to optimally adjusting behavioral strategies in competitive situations.  相似文献   

9.
Beach volleyball is a sport with a high demand of shoulder structures that may lead to adaptations in range of motion (ROM) and strength like in other overhead sports. Despite of these possible alterations, no study evaluated the shoulder adaptations in young beach volleyball athletes. The aim of this study was to compare the bilateral ROM and rotation strength in the shoulders of young beach volleyball players. Goniometric passive shoulder ROM of motion and isometric rotational strength were evaluated in 19 male and 14 female asymptomatic athletes. External and internal ROM, total rotation motion, glenohumeral internal rotation deficit (GIRD), external rotation and internal rotation strength, bilateral deficits and external rotation to internal rotation ratio were measured. The statistical analysis included paired Student’s t-test and analysis of variance with repeated measures. Significantly lower dominant GIRD was found in both groups (p < 0.05), but only 6 athletes presented pathological GIRD. For strength variables, no significant differences for external or internal rotation were evident. Young beach volleyball athletes present symmetric rotational strength and shoulder ROM rotational adaptations that can be considered as anatomical. These results indicate that young practitioners of beach volleyball are subject to moderate adaptations compared to those reported for other overhead sports.  相似文献   

10.
Using a randomized crossover design, this study aimed to compare the heart rate (HR) responses and match analysis parameters (i.e., type of action; the number of players involved in an action; the number of passes performed in a collective action; precision of the shots; lost balls; ball interceptions; dribblings; and tackles) of official 5-a-side youth male soccer matches played over 2 pitch surface (i.e., clay vs. artificial turf) conditions. Twenty-two young male soccer players (age 8.3 ± 0.4 years) engaged in 2 consecutive 15-minute periods in each experimental condition. During the match, 53% of HR responses exceeded 85% of the individual HR(peak). No difference emerged between both pitch surfaces and match periods for HR and match analysis indicators. The two 15-minute periods resulted in being appropriate for 8-year-old players, in resembling the intensity of play and the intermittent nature of adult soccer. The similar HR responses and technical-tactical patterns observed on the 2 surfaces indicate that youth match play is not affected by differences in pitch surface. To support the development of individual and team skills of young soccer players, coaches are advised to prioritize game knowledge based on divergent thinking and experience, rather than traditional teaching based on instructions.  相似文献   

11.
The aim of the study was to identify morphological structures of young female volleyball players according to age, and to assess the impact of these morphological structures on technical and situation efficacy. A set of 13 morphological measures as predictor variables, a set of 6 technique elements, and assessment of performance quality as criterion variables were employed in a sample of 246 female volleyball players. The sample consisted of 32 players aged 12-13, 147 players aged 14-15, 50 players aged 16-17, and 17 players aged 18-19. Analysis of variance showed the female volleyball players of various age groups to differ significantly according to the variables assessing the longitudinal skeleton dimensionality, and body mass and volume, as well as in all tests used on volleyball technique evaluation. Factor analysis of morphological measures applied across all age groups generally yielded two morphological structures: the one determined by skeleton development, i.e. longitudinal and transverse bone growth, and another one determined by soft tissue development, i.e. muscle and adipose tissue growth. Results of regression analysis revealed the longitudinal skeleton dimensionality to significantly determine the block technique performance across all age groups, and to a lesser extent performance of the spike technique in the 14-15 and 16-17 age groups. Regression correlation analysis also showed the developed skeleton based on the predominance of longitudinality to be a significant positive predictor of situation performance in all age groups.  相似文献   

12.
The authors presumed that it was possible to replace certain criteria of the expert system aimed at evaluating actual quality of basketball players, proposed by Trnini? et al., with the corresponding indicators of situation-related efficiency (official statistics of the game). Hence, the aim of this study is to verify the potential of establishing such a combined model of expert system that would consist of both the evaluation criteria and certain number of objectively measurable aspects of actual quality (player's partial performance or playing efficiency) and to determine its pragmatic validity. To achieve the aim the sample comprised of 60 basketball players that were competing in the Croatian First Division League in the 1998/99 season was tested. The sample and their quality of play was described by the two different types of data: 1) the 13 situation-related efficiency data (FIBA statistics of the game) utilized to objectively assess performance or playing effectiveness of players, collected at 132 games played by 12 teams, and 2) the evaluation data, subjectively assessing actual quality of players, i.e. their perceived overall performance, collected at the end of the season from the 10 basketball trainers. On the basis of relatively high correlations within the 7 pairs of mutually equivalent variables (from 0.63 to 0.84) and the extremely high correlation (0.97) obtained between the perceived overall performance (actual quality), subjectively assessed with respect to the 19 criteria of the original expert evaluation system, and the overall performance (actual quality) assessed by the combined model (where the 8 evaluation criteria had been replaced by the 7 corresponding indicators ofplaying efficiency), it is feasible to consider the combined model of expert system as an acceptable tool for more objective and economical assessment of actual quality of basketball players.  相似文献   

13.
Cooperation is an integral part of human social life and we often build teams to achieve certain goals. However, very little is currently understood about emotions with regard to cooperation. Here, we investigated the impact of social context (playing alone versus playing on a team) on emotions while winning or losing a game. We hypothesized that activity in the reward network is modulated by the social context and that personality characteristics might impact team play. We conducted an event-related functional magnetic resonance imaging experiment that involved a simple game of dice. In the team condition, the participant played with a partner against another two-person team. In the single-player condition, the participant played alone against another player. Our results revealed that reward processing in the right amygdala was modulated by the social context. The main effect of outcome (gains versus losses) was associated with increased responses in the reward network. We also found that differences in the reward-related neural response due to social context were associated with specific personality traits. When playing on a team, increased activity in the amygdala during winning was a unique function of openness, while decreased activity in the ventromedial prefrontal cortex and ventral striatum during losing was associated with extraversion and conscientiousness, respectively. In conclusion, we provide evidence that working on a team influences the affective value of a negative outcome by attenuating the negative response associated with it in the amygdala. Our results also show that brain reward responses in a social context are affected by personality traits related to teamwork.  相似文献   

14.
It is known from primates that alliance partners may support each other's interests in competition with others, for example, through repeated agonistic attacks against a particular individual. We examined serial aggressive interactions between greylag goose families and other flock members. We found that repeated attacks towards the same individual were common and that up to five serial attacks by family members followed an initial attack. Family size did not affect the frequency of such serial attacks. Juvenile geese evidently benefited most from active social support through serial attacks. About 60% of the juveniles' lost primary interactions were subsequently reversed by another family member. This may be one of the reasons why juveniles rank higher in the social hierarchy than would be expected from their age and size alone. Losses in serial attacks predominantly occurred against other, presumably higher-ranking, family geese and ganders. We propose three major functions/consequences of serial attacks. Analogous to primates, serial attacks in greylag geese may serve to reinforce a losing experience of an opponent defeated in a preceding attack. On the side of the winning family, serial attacks may reinforce the experience of winning. Both winning and losing experiences are linked with physiological consequences in higher vertebrates, affecting the future social performance of winners or losers. Finally, serial attacks may signal the agonistic potential of a family to other flock members. This is supported by heart rate data, which indicate that greylags are competent to interpret third-party relationships.  相似文献   

15.
根据“兴林灭螺”产生背景,发展现状和重要影响,阐述滩地灭螺林与其他林种之间的区别,滩地灭螺林除具有灭螺防病的功能之外,还有其特殊的地理环境,特定的树咎构成,特异的营造技术和林相结构;总结滩地灭螺林的经营原则是超强度集约经营,短周期经营,规模经营和综合经营,因此滩地灭螺林在林业生产中应划分为一个新的林种,提出长江中下游沿江地区新的林种结构是滩地灭螺林、防护林,经济林与景观游憩林,并就如何加快发展滩地  相似文献   

16.
The purpose of the present study was to analyse men's basketball competitions, trying to identify which game-related statistics allow to discriminate winning and losing teams. The sample used corresponded to 306 games from the 2004-2005 Regular Season of the Spanish Men's Professional League. The game-related statistics gathered were: 2 and 3 points field-goals (both successful and unsuccessful), free-throws (both successful and unsuccessful), offensive and defensive rebounds, blocks, assists, fouls, turnovers and steals. The data were analysed in two groups: balanced games (final score differences equal or below 12 points) and unbalanced games (final score differences above 12 points). Discriminant analysis allowed to conclude the following: (i) in balanced games, the variable that best differentiate both groups were the defensive rebounds; (ii) in unbalanced games, the variables that discriminate between both groups were the successful 2 points field-goals, the defensive rebounds and the assists; and (iii) in all games, the statistical analysis identified two variables that discriminate winning and losing teams (defensive rebounds and assists). The defensive rebounds were the only game-related statistic that discriminates both groups in all performed analysis. Coaches and players should be aware of these different profiles in order to increase knowledge about game cognitive and motor solicitation and, therefore, to enhance specificity at the time of practice and game planning.  相似文献   

17.
The purpose of this paper was: a) to provide reference values for the standing spike test for female volleyball players and b) to study whether the standing spike test is valid for assessing the theoretical differences between female volleyball players. The sample included 83 players from the first nine teams of the Spanish women''s first volleyball division (52 Spanish players and 31 from other nationalities). The variables studied were the ball speed of the standing spike test, the age of the players, the player''s role (outside hitter, opposite, middle-blocker, libero, or setter), height, and nationality of the players (Spanish or foreign). The results demonstrate the ranges for the standing spike among female performance volleyball players (70-82 km · h−1). The differences regarding nationality, player role, height, and age seem to indicate that the test is a valid instrument for monitoring the performance of female volleyball players.  相似文献   

18.
The aim of this study was to investigate recovery via analysis of activity profiles in a professional soccer team over an intense period of matches. A total of 172 outfield players from 27 Spanish League matches played by a professional team during the 2005-2006 season were analyzed using a multiple-camera match analysis system. The dependent variables were the distance covered by players at different intensities. Data were analyzed using an independent-sample t-test and a linear regression analysis with 5 independent variables: the number of matches played per week (1 or 2), match status (i.e., whether the team was winning, losing or drawing), match location (i.e., playing at home or away), quality of the opponents (strong or weak), and the individual playing position of the players. The main finding of this study suggests that the activity profiles of professional soccer players were not influenced by short recovery between matches. Although those players who played 2 matches a week covered less distance at maximal (>23 km·h(-1)), submaximal (19.1-23 km·h(-1)), and medium (14.1-19 km·h(-1)) intensities than those players who played 1 match a week, no significant differences were found. Moreover, results from this study seem to confirm that the elite soccer players' distance covered at various speeds is dependent on match contextual factors. The top-class players performed less high-intensity activity (>19.1 km·h(-1)) when winning than when they were losing (p < 0.05), but more distance was covered by walking and jogging when winning (p < 0.05). The home teams covered a greater distance than away teams at low intensity (<14.1 km·h(-1)) (p < 0.01). Finally, the better the quality of the opponent, the higher the distance covered by walking and jogging.  相似文献   

19.
The purpose of this study was to investigate the effect of changes in field size on the physiological and skill demands of small-sided games in elite junior and senior rugby league players. Sixteen elite senior rugby league players ([mean ± SE] age, 23.6 ± 0.5 years) and 16 elite junior rugby league players ([mean ± SE] age, 17.3 ± 0.3 years) participated in this study. On day 1, 2 teams played an 8-minute small-sided game on a small field (10-m width × 40-m length), whereas the remaining 2 teams played the small-sided game on a larger sized field (40-m width × 70-m length). On day 2, the groups were crossed over. Movement was recorded by a global positioning system unit sampling at 5 Hz. Games were filmed to count the number of possessions and the number and quality of disposals. The games played on a larger field resulted in a greater (p < 0.05) total distance covered, and distances covered in moderate, high, and very-high velocity movement intensities. Senior players covered more distance at moderate, high, and very-high intensities, and less distance at low and very-low intensities during small-sided games than junior players. Although increasing field size had no significant influence (p > 0.05) over the duration of recovery periods for junior players, larger field size significantly reduced (p < 0.05) the amount of short-, moderate-, and long-duration recovery periods in senior players. No significant between-group differences (p > 0.05) were detected for games played on a small or large field for the number or quality of skill involvements. These results suggest that increases in field size serve to increase the physiological demands of small-sided games but have minimal influence over the volume or quality of skill executions in elite rugby league players.  相似文献   

20.
Don't count the US out of the HDTV game just yet. For starters, we're changing the rules of the game. The new terminology being bandied about is high resolution systems instead of merely high definition, as proposed for Japan and Europe, which some here in the States regard as old technology.  相似文献   

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