Expectancy effects in tennis: The impact of opponents' pre-match non-verbal behaviour on male tennis players

Abstract

In this study, we examined the impact of a male opponent's pre-match body language and clothing (general vs. sports-specific) on how his performances were judged by an observer. Forty male tennis players viewed videos of a male target tennis player warming up and then observed playing footage of the target. Each participant viewed the target player warming up displaying one of four combinations of body language and clothing (positive body language/tennis-specific clothing; positive body language/general sportswear; negative body language/tennis-specific clothing; negative body language/general sportswear). Participants rated the performance of the tennis player and gave their perceptions of the likely outcome of a tennis match with the target player. Analyses of variance indicated that clothing and body language had an interactive effect on both outcome expectations and ratings of performance. The findings support the contention that the initial impressions athletes form of their opponents can influence the way in which they judge the performances of opponents and their perceived likelihood of success against the same opponents.     

A case study comparison of objective and subjective evaluation methods of physical qualities in youth soccer players

ABSTRACT

Subjective and objective assessments may be used congruently when making decisions regarding player recruitment in soccer, yet there have been few attempts to examine the level of agreement between these methods. Therefore, we compare levels of agreement between subjective and objective assessments of physical qualities associated with youth soccer performance. In total, 80 male youth soccer players (13.2 ± 1.9 years), and 12 professional coaches volunteered to participate. Players were objectively assessed using five fitness measures: Yo-Yo Intermittent Recovery Test Level 1; Countermovement vertical jump; Functional Movement Screen?; 5/20 m sprint; alongside anthropometric measures. Additionally, coaches subjectively rated each player on the same five physical qualities using 5-point Likert scales. Inter-rater agreement between ratings from lead and assistant coaches was established for each age group. Moreover, Bayesian regression models were fitted to determine how well coach ratings were able to predict fitness test performance. Although inter-rater agreement between lead and assistant coaches was moderate-to-substantial (ω = 0.48–0.68), relationships between coaches subjective rating’s and corresponding fitness test performance were only highly related for the highest and lowest performing players. We suggest that while ratings derived from objective and subjective assessment methods may be related when attempting to differentiate between distinct populations, concerns exist when evaluating homogeneous samples using these methods. Our data highlight the benefits of using both types of measures in the talent identification process.     

Coaching Efficacy,Player Perceptions of Coaches’ Leadership Styles,and Team Performance in Premier League Soccer

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 (M_age = 45.27, SD = 6.07) and 226 players (M_age = 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.     

Coordination as a function of skill level in the gymnastics longswing

The purpose of this study was to investigate the nature of inter-joint coordination at different levels of skilled performance to: (1) distinguish learners who were successful versus unsuccessful in terms of their task performance; (2) investigate the pathways of change during the learning of a new coordination pattern and (3) examine how the learner’s coordination patterns relate to those of experts in the longswing gymnastics skill. Continuous relative phase of hip and shoulder joint motions was examined for longswings performed by two groups of novices, successful (n = 4) and unsuccessful (n = 4) over five practice sessions, and two expert gymnasts. Principal component analysis showed that during longswing positions where least continuous relative phase variability occurred for expert gymnasts, high variability distinguished the successful from the unsuccessful novice group. Continuous relative phase profiles of successful novices became more out-of-phase over practice and less similar to the closely in-phase coupling of the expert gymnasts. Collectively, the findings support the proposition that at the level in inter-joint coordination a technique emerges that facilitates successful performance but is not more like an expert’s movement coordination. This finding questions the appropriateness of inferring development towards a “gold champion” movement coordination.     

The influence of in-game emotions on basketball performance

Abstract

This study examined the influence of emotions on performance in basketball. Six female basketball players were videotaped in six games. Frequency of performance behaviours was recorded minute-by-minute and indices of successful (SGI) and unsuccessful (UGI) game involvement derived for each player. Post-game, players reported the intensity of experienced emotions (anger, anxiety, embarrassment, excitement and happiness), and the time of the eliciting incident. The only emotion revealed as a significant predictor of SGI was happiness; both anger and embarrassment were significant predictors of increased UGI. Consideration of individual player analyses suggests that there is variation in the magnitude of the influence of emotions on performance and the extent to which this influence was helpful or harmful to performance. The study provides evidence that emotions are associated with changes in game behaviours in competition. Implications for further research examining the emotion–performance relationship are discussed.     

The Effects of Training and Position on Judges' Ratings of a Gymnastic Event

The purpose of this study was to determine the effects of training and position on judges' ratings of a gymnastic event. Twenty-four women judged the performance of the squat vault by 40 college women. The judges were divided into four groups. Two groups received written training, and two groups, extensive training. After completing their training, one written group and one extensive group viewed the performances from the side of the vaulting box; the other two groups viewed from the front of the vaulting box. Judge position and judge training were found to have significant effects upon judges' ratings. Significantly lower ratings were given by the judges who viewed the vault from the front and had received extensive training.     

Expectancy effects in tennis: the impact of opponents' pre-match non-verbal behaviour on male tennis players

In this study, we examined the impact of a male opponent's pre-match body language and clothing (general vs. sports-specific) on how his performances were judged by an observer. Forty male tennis players viewed videos of a male target tennis player warming up and then observed playing footage of the target. Each participant viewed the target player warming up displaying one of four combinations of body language and clothing (positive body language/tennis-specific clothing; positive body language/general sportswear; negative body language/tennis-specific clothing; negative body language/general sportswear). Participants rated the performance of the tennis player and gave their perceptions of the likely outcome of a tennis match with the target player. Analyses of variance indicated that clothing and body language had an interactive effect on both outcome expectations and ratings of performance. The findings support the contention that the initial impressions athletes form of their opponents can influence the way in which they judge the performances of opponents and their perceived likelihood of success against the same opponents.     

Using Skill Tests to Identify Successful and Unsuccessful Basketball Performers

The purpose of this study was to investigate the relationship of 21 selected basketball skill tests to successful basketball performance. The 21 skill test items were administered to 70 boys ranging in age from 12 to 17 attending the 1977 University of Minnesota-Duluth basketball camp for boys. Based on the ratings of three high school and three college coaches, camp participants were designated as successful (n = 32) and unsuccessful (n = 38) performers. The stepwise discriminant analysis procedure was used. Six skill tests were identified as significantly contributing to discriminating between group membership. These tests, in order of the magnitude of their standardized discriminant function coefficients, were (1) speed pass, (2) zig-zag run, (3) free jump, (4) side step, (5) front shot, and (6) zig-zag dribble. It was concluded that a basketball skill test battery comprised of these six test items would objectively measure basketball playing ability and discriminate between successful and unsuccessful performers.     

Mental fatigue impairs soccer-specific decision-making skill

ABSTRACT

This study aimed to investigate the impact of mental fatigue on soccer-specific decision-making. Twelve well-trained male soccer players performed a soccer-specific decision-making task on two occasions, separated by at least 72 h. The decision-making task was preceded in a randomised order by 30 min of the Stroop task (mental fatigue) or 30 min of reading from magazines (control). Subjective ratings of mental fatigue were measured before and after treatment, and mental effort (referring to treatment) and motivation (referring to the decision-making task) were measured after treatment. Performance on the soccer-specific decision-making task was assessed using response accuracy and time. Visual search behaviour was also assessed throughout the decision-making task. Subjective ratings of mental fatigue and effort were almost certainly higher following the Stroop task compared to the magazines. Motivation for the upcoming decision-making task was possibly higher following the Stroop task. Decision-making accuracy was very likely lower and response time likely higher in the mental fatigue condition. Mental fatigue had unclear effects on most visual search behaviour variables. The results suggest that mental fatigue impairs accuracy and speed of soccer-specific decision-making. These impairments are not likely related to changes in visual search behaviour.     

A biomechanical comparison of successful and unsuccessful power clean attempts

Although the power clean is an almost ubiquitous exercise in the strength and conditioning setting, relatively little is known about the biomechanics of successful and unsuccessful power clean lift attempts. The purpose of this study was to determine biomechanical differences between successful and unsuccessful power clean lift attempts in male collegiate athletes. Fifteen male lacrosse players (Age: 20.1 ± 1.2; Height: 1.78 ± 0.07 m; Body mass: 80.4 ± 8.1 kg; Relative one-repetition maximum power clean: 1.25 ± 0.13 kg/kg) were videotaped during a lifting session that required the completion of maximal effort power cleans to establish a one-repetition maximum. The position of the barbell was digitised and used to calculate the displacement, velocity, acceleration, and acceleration vector of the barbell. The results revealed that unsuccessful attempts were characterised by differences during the second pull phase. Unsuccessful lifts exhibited greater peak forward barbell displacement, lower backward barbell velocities, and lower resultant acceleration angles during the second pull. Strength and conditioning coaches should therefore emphasise limited forward motion of the barbell during the second pull and instruct athletes to generate a more backward-directed force during the second pull in order to lift greater loads during testing and subsequent lifting sessions.     

Peak athletic performance and ageing: Evidence from baseball

Abstract

Baseball players exhibit a pattern of improvement and decline in performance; however, differing lengths of careers and changes in rules and characteristics of the game complicate assessments of age-related effects on performance. This study attempts to isolate the impact of age on several player skills while controlling for relevant outside factors using longitudinal data from 86 seasons of Major League Baseball. The results indicate that players age in different skills in accord with studies of ageing in other athletic contests. For overall performance, multiple-regression estimates indicate that hitters and pitchers peak around the age of 29 – later than previous estimates. Athletic skills such as hitting and running peak earlier than skills that rely heavily on experience and knowledge, such as issuing and drawing walks.     

Delayed Visual Feedback While Learning to Track a Moving Target

Abstract

Two studies investigated the effects of delayed visual feedback on manual tracking. In Experiment 1, individuals practiced with visual feedback provided either immediately (0 delay) or with a 333-ms delay. During acquisition, the 0 delay group performed with less error than the 333-ms delay group. A retention test with 0 delay feedback was performed with the least error by the 0 delay group. A transfer test using a different 0 delay tracking pattern, was performed with the least error by the 333-ms delay group. In Experiment 2, individuals practiced at six different delays. Error increased as training feedback delay increased. For retention there were no differences between the delay groups during the 0 delay retention. At a 417-ms retention, test error decreased as training feedback delay increased. Results indicate that error during acquisition does not necessarily impair learning and that feedback delays can be beneficial for learning.     

The moral worth of sport reconsidered: Contributions of recreational sport and competitive sport to life aspirations and psychological well-being

Abstract

Based on self-determination theory, the present study aimed to test the hypothesis that importance ratings of life aspirations would mediate the effects of participation in recreational and competitive sport on psychological well-being. In addition, the effects of sport participation on psychological well-being were hypothesized to indicate that, compared with competitive athletes, recreational athletes would report higher psychological well-being. The participants were 118 university students (83 males, 35 females) with a mean age of 20.8 years (s = 7.6). In accordance with the initial hypotheses, a path analysis supported the mediating effect of importance ratings of life aspirations, but not of attainment ratings of life aspirations, on the relationship between participation in recreational and competitive sport and psychological well-being. The indirect effects observed for importance ratings supported the conclusion that recreational athletes showed a preference for intrinsic life aspirations compared with competitive athletes and reported higher psychological well-being. Overall, the findings of the present study suggest that the moral worth of sport does not reside so much in the frequency with which individuals engage in sport but in the goals and values people express through sport participation.     

Scaling Constraints in Junior Tennis: The Influence of Net Height on Skilled Players’ Match-Play Performance

Purpose: The net height in tennis (0.91 m) is approximately 50% of a professional tennis player’s height. Children are also expected to play with this net height, even though it is approximately 70% of the average 10-year-old’s height. This study examined the immediate effect of lowering net height on the performance characteristics of skilled junior tennis players aged 10 years and younger. Method: Sixteen players were matched in 8 pairs of even tennis ability and same sex. Each pair played 25-min singles matches in 4 conditions that varied in net height (0.91 m, 0.78 m, 0.65 m, and 0.52 m). Match-play characteristics were analyzed via video replay. Results: Results showed that lowering the net height to 0.65 m and 0.52 m led to players adopting a more attacking style of play, as evidenced by a significant increase in the number of winners without a commensurate increase in errors and more shots struck inside the baseline. Lower nets also led to a greater percentage of successful first serves. The lowest net (0.52 m), however, reduced rally length significantly and therefore decreased hitting opportunities. Conclusion: These results offer support for equipment scaling to enhance match-play performance for skilled junior tennis players. We propose that current net height recommendations for junior tennis should be revised.     

Network analysis of kick-in possession chains in elite Australian football

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.     

The importance of being elastic: Deflection of a badminton racket during a stroke

Abstract

The deflection profiles of a badminton racket during strokes performed by elite and world-class badminton players were recorded by strain gauges and subsequently analysed to determine the role of shaft stiffness in racket performance. Deflection behaviour was consistent in all strokes across all players, suggesting a controlled use of racket elasticity. In addition, all impacts occurred within 100 ms of each other, a duration in which deflection velocity provides an increase in racket velocity, indicating that the players were able to use racket elasticity to their advantage. Since deflection behaviour is a product of the racket–player interaction, further work is required to determine the effects of different racket properties and player techniques on the elastic response of rackets during strokes.     

网球运动员目标定向与归因方式的研究

随着网球运动在中国飞速发展,网球运动的研究也成为体育领域中关注的论题。对网球运动员目标定向与归因方式的研究还比较缺乏。鉴于研究应用心理测量法对网球运动员的目标定向和归因方式进行探讨。了解中国网球运动员的目标定向及归因方式的现状,丰富运动员对目标定向和归因方式的认识。研究结果显示：网球运动员的目标定向在性别上存在显著性差异;网球运动员基本归因类型,在成功情境下为：内部的、稳定的、可控的;在失败情境下为：内部的、稳定的、不可控的;网球运动员在成功情境下的归因方式没有性别差异,在失败情境下内外源、稳定性存在性别差异;网球运动员的目标定向与归因方式的相关性不高,存在着低度相关。     

Basketball game-related statistics that discriminate between teams’ season-long success

Abstract

The aim of the present study was to identify the game-related statistics that discriminate between season-long successful and unsuccessful basketball teams participating in the Spanish Basketball League (LEB1). The sample included all 145 average records per season from the 870 games played between the 2000–2001 and the 2005–2006 regular seasons. The following game-related statistics were gathered from the official box scores of the Spanish Basketball Federation: 2- and 3-point field-goal attempts (both successful and unsuccessful), free-throws (both successful and unsuccessful), defensive and offensive rebounds, assists, steals, turnovers, blocks (both made and received), and fouls (both committed and received). To control for season variability, all results were normalized to minutes played each season and then converted to z-scores. The results allowed discrimination between best and worst teams’ performances through the following game-related statistics: assists (SC=0.47), steals (SC=0.34), and blocks (SC=0.30). The function obtained correctly classified 82.4% of the cases. In conclusion, season-long performance may be supported by players’ and teams’ passing skills and defensive preparation.     

American Association for Health,Physical Education,and Recreation

ABSTRACT

Purpose: The purpose of this study was to identify whether post-resistance exercise (REx) blood flow restriction (BFR) can elicit a similar acute training stimulus to that offered by either heavy REx or traditional low-load BFR REx. Method: Ten men completed trials with 30% one-repetition maximum (1RM) for 5 sets of 15 repetitions without BFR (30%), with BFR during exercise (30% RD), and with postexercise BFR (30% RP) and at 75% 1RM for 3 sets of 10 repetitions. Lactate and cortisol were measured before and up to 60 min after exercise. Thigh circumference, ratings of perceived exertion (RPE), and pain were measured before and after exercise. Surface electromyography was measured during exercise. Results: All conditions had a large effect (effect size [ES] > 0.8) on lactate, with the largest effects observed with the 75% condition; no differences were observed between the 30% conditions. All conditions had a moderate effect (ES > 0.25 ≤ 0.4) on increasing thigh circumference. This effect was maintained (ES = 0.35) with the application of BFR after REx (30% RP). Change in RPE, from the first to last set, was significantly greater with 30% RD compared with other conditions (all p < .05). Electromyography amplitude was higher and percentage change was greater for the 75% condition compared with the other conditions (both p < .05). Conclusions: The application of BFR immediately post-REx altered several of the responses associated with REx that is aimed at inducing muscular hypertrophy. Additionally, these changes occurred with less pain and perceived exertion suggesting that this form of REx may offer an alternative, tolerable method of REx.