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The research aims to : 1 .Identify the level of self-confidence among female volleyball players in the Kurdistan region . 2 .Identify the level of competitive behavior among female volleyball players in the Kurdistan region . 3 .Explore the relationship between self-confidence and competitive behavior among female volleyball players in the Kurdistan region . The researcher employed a descriptive methodology using correlational relationships, which is suitable for the nature and problem of the research. The research community consisted of volleyball players from sports clubs (Sanhareeb, Akkad Ankawa, Dibbandikhan, Sulaimaniyah, Armenian, Qaraqosh, and Erbil Girls) participating in the Northern Region Clubs Volleyball League in the Kurdistan region for the 2022-2023 season, totaling 101 players from 7 clubs. The research sample comprised 80 players, representing 79.20% of the population distributed across the clubs. Six players were excluded for incomplete questionnaires, 10 players for participating in the pilot study, and 5 players for control purposes. The researcher utilized statistical methods such as percentages, means, standard deviations, hypothetical average, and Pearson correlation coefficient for data analysis. The researcher reached several conclusions, including : -Female volleyball players in the Kurdistan region possess a positive and acceptable level of self-confidence . -Female volleyball players in the Kurdistan region exhibit a positive level of competitive behavior . -There is a significant and positive correlation between self-confidence and competitive behavior among female volleyball players in the Kurdistan region. [ABSTRACT FROM AUTHOR]

Background and Objectives: This retrospective case-control study aimed to investigate the quality of life (QoL) of young gastric cancer survivors and determine what should be pursued to obtain the best QoL for them after surgery. Materials and Methods: Patients with stage I gastric cancer who underwent distal subtotal gastrectomy were included. The European Organization for Research and Treatment of Cancer Quality of Life questionnaires were used to assess QoL. The QoL outcomes of younger (age 30–49 years, n = 76) and older (age 50–69 years, n = 232) groups were compared preoperatively, 3 months, and 1 year postoperatively. Results: There was no statistically significant difference in the preoperative QoL except for the physical functioning scale, which favored the younger group (p = 0.020). This difference remained significant throughout the postoperative periods (3 months, p = 0.002; 1 year, p = 0.004). Better QoL was found for the younger group according to the body image scale (p = 0.031). However, it was limited to the 3-month postoperative assessment. Persistent QoL disadvantages for the younger group were revealed by the diarrhea scale at the 3-month (p = 0.007) and 1-year (p = 0.005) postoperative assessments. Conclusions: While young gastric cancer survivors enjoyed better QoL in physical functioning and body image, worse QoL was related to diarrhea after surgery. Despite ever-rising concerns about QoL deterioration in elderly patients in our aged society, young gastric cancer survivors also need QoL support. [ABSTRACT FROM AUTHOR]

Sexual dimorphism is a ubiquitous source of within-species variation, yet the community-level consequences of sex differences remain poorly understood. Here, we analyse a bitrophic model of two competing resource species and a sexually reproducing consumer species. We show that consumer sex differences in resource acquisition can have striking consequences for consumer-resource coexistence, abundance and dynamics. Under both direct interspecific competition and apparent competition between two resource species, sexual dimorphism in consumers attack rates can mediate coexistence of the resource species, while in other cases can lead to exclusion when stable coexistence is typically expected. Slight sex differences in total resource acquisition also can reverse competitive outcomes and lead to density cycles. These effects are expected whenever both consumer sexes require different amounts or types of resources to reproduce. Our results suggest that consumer sexual dimorphism, which is common, has wide-reaching implications for the assembly and dynamics of natural communities.

Social primates face conflicts of interest with other partners when their individual and collective interests collide. Despite living in small, primarily bonded, groups compared to other social primates, gibbons are not exempt from these conflicts in their everyday lives. In the current task, we asked whether dyads of gibbons would solve a conflict of interest over food rewards. We presented dyads of gibbons with a situation in which they could decide whether to take an active role and pull a handle to release food rewards at a distance or take a passive role and avoid action. In this situation, the passive partner could take an advantageous position to obtain the rewards over the active partner. Gibbons participated in three conditions: a control condition with no food rewards, a test condition with indirect food rewards and a test condition with direct food rewards. In both test conditions, five rewards were released at a distance from the handle. In addition, the active individual could obtain one extra food reward from the handle in the direct food condition. We found that gibbons acted more often in the two conditions involving food rewards, and waited longer in the indirect compared to the direct food condition, thus suggesting that they understood the task contingencies. Surprisingly, we found that in a majority of dyads, individuals in the active role obtained most of the payoff compared to individuals in the passive role in both food conditions. Furthermore, in some occasions individuals in the active role did not approach the location where the food was released. These results suggest that while gibbons may strategize to maximize benefits in a competitive food task, they often allowed their partners to obtain better rewards. Our results highlight the importance of social tolerance and motivation as drivers promoting cooperation in these species.

In a Dutch auction, an item is offered for sale at a set maximum price. The price is then gradually lowered over a fixed interval of time until a bid is made, securing the item for the bidder at the current price. Bidders must trade-off between certainty and price: bid early to secure the item and you pay a premium; bid later at a lower price but risk losing to another bidder. These properties of Dutch auctions provide new opportunities to study competitive decision-making in a group setting. We developed a novel computerised Dutch auction platform and conducted a set of experiments manipulating volatility (fixed vs varied number of items for sale) and price reduction interval rate (step-rate). Triplets of participants ([Formula: see text]) competed with hypothetical funds against each other. We report null effects of step-rate and volatility on bidding behaviour. We developed a novel adaptation of prospect theory to account for group bidding behaviour by balancing certainty and subjective expected utility. We show the model is sensitive to variation in auction starting price and can predict the associated changes in group bid prices that were observed in our data.

Research Summary: We apply a resource‐based view to investigate how the adoption of Artificial Intelligence (AI) affects competitive capabilities and performance. Following prior work on using chess as a controlled setting for studying competitive interactions, we compare the same players' capabilities and performance across conventional, centaur, and engine chess tournaments. Our analysis shows that AI adoption triggers interrelated substitution and complementation dynamics, which make humans' traditional competitive capabilities obsolete, while creating new sources of persistent heterogeneity when humans interact with chess engines. These novel human‐machine capabilities are unrelated, or even negatively related, to traditional capabilities. We contribute an integrated view of substitution and complementation, which identifies AI as the driver of these dynamics and explains how they jointly shift the sources of competitive advantage. Managerial Summary: AI‐based technologies increasingly substitute and complement humans in managerial tasks such as decision making. We investigate how such change affects the sources of competitive advantage. AI‐based engines' adoption in chess allows us to investigate competitive capabilities and performance in human, AI, and hybrid settings. We find that neither humans nor AI in isolation explain performance differences in the AI and hybrid settings. Instead, a new decision‐making resource emerges at the human‐AI intersection, which drives performance but is unrelated or even negatively related to humans' original capability. Our results document how AI adoption changes the sources of competitive advantage and, in turn, requires managers to develop new capabilities to stay relevant in an AI‐based competitive landscape. [ABSTRACT FROM AUTHOR]

Through its behavior, an organism intentionally or unintentionally produces information. Use of this "social information" by surrounding conspecifics or heterospecifics is a ubiquitous phenomenon that can drive strong correlations in fitness-associated behaviors, such as predator avoidance, enhancing survival within and among competing species. By eliciting indirect positive interactions between competing individuals or species, social information might alter overall competitive outcomes. To test this potential, we present new theory that quantifies the effect of social information, modeled as predator avoidance signals/cues, on the outcomes from intraspecific and interspecific competition. Our analytical and numerical results reveal that social information can rescue populations from extinction and can shift the long-term outcome of competitive interactions from mutual exclusion to coexistence, or vice versa, depending on the relative strengths of intraspecific and interspecific social information and competition. Our findings highlight the importance of social information in determining ecological outcomes.

Copyright of Revista Brasileira de Medicina do Esporte is the property of Redprint Editora Ltda. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Brasileira de Medicina do Esporte is the property of Redprint Editora Ltda. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Brasileira de Medicina do Esporte is the property of Redprint Editora Ltda. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Gender imbalances in the labor market continue to be an economic and social problem that could be reduced by artificial intelligence (AI), which is being promoted as a means for fairer and less biased hiring practices. To examine whether these supposed benefits of AI are perceived as such, we have investigated the preferences of individuals, particularly women, for an AI-based evaluation process in a competitive situation. The results of our experimental study (N = 152) show that individuals generally prefer a human evaluator over an AI evaluator—but only if the human evaluator is female. Whereas we demonstrate that women's beliefs in AI to reduce bias and perceived personal discrimination have a positive direct effect, we find no direct effect of the competitors' gender on women's preference for an AI evaluation. However, we find that the belief in AI moderates the other two relationships, which highlights the crucial role of people's general perception of AI tools in realizing AI's full potential and reduce anticipated biases. Our findings provide an initial indication that the use of AI technology in hiring could encourage women to apply for jobs in male-dominated fields and serve as a starting point for future research in this field.

Background and Objectives: This retrospective case-control study aimed to investigate the quality of life (QoL) of young gastric cancer survivors and determine what should be pursued to obtain the best QoL for them after surgery. Materials and Methods: Patients with stage I gastric cancer who underwent distal subtotal gastrectomy were included. The European Organization for Research and Treatment of Cancer Quality of Life questionnaires were used to assess QoL. The QoL outcomes of younger (age 30–49 years, n = 76) and older (age 50–69 years, n = 232) groups were compared preoperatively, 3 months, and 1 year postoperatively. Results: There was no statistically significant difference in the preoperative QoL except for the physical functioning scale, which favored the younger group (p = 0.020). This difference remained significant throughout the postoperative periods (3 months, p = 0.002; 1 year, p = 0.004). Better QoL was found for the younger group according to the body image scale (p = 0.031). However, it was limited to the 3-month postoperative assessment. Persistent QoL disadvantages for the younger group were revealed by the diarrhea scale at the 3-month (p = 0.007) and 1-year (p = 0.005) postoperative assessments. Conclusions: While young gastric cancer survivors enjoyed better QoL in physical functioning and body image, worse QoL was related to diarrhea after surgery. Despite ever-rising concerns about QoL deterioration in elderly patients in our aged society, young gastric cancer survivors also need QoL support.

Social interactions involve complex decision-making tasks that are shaped by dynamic, mutual feedback between participants. An open question is whether and how emergent properties may arise across brains of socially interacting individuals to influence social decisions. By simultaneously performing microendoscopic calcium imaging in pairs of socially interacting mice, we find that animals exhibit interbrain correlations of neural activity in the prefrontal cortex that are dependent on ongoing social interaction. Activity synchrony arises from two neuronal populations that separately encode one's own behaviors and those of the social partner. Strikingly, interbrain correlations predict future social interactions as well as dominance relationships in a competitive context. Together, our study provides conclusive evidence for interbrain synchrony in rodents, uncovers how synchronization arises from activity at the single-cell level, and presents a role for interbrain neural activity coupling as a property of multi-animal systems in coordinating and sustaining social interactions between individuals.

The present lack of sample diversity and ecological theory in psychological science fundamentally limits generalizability and obstructs scientific progress. A focus on the role of socioecology in shaping the evolution of morphology, physiology, and behavior has not yet been widely applied toward psychology. To date, evolutionary approaches to psychology have focused more on finding universals than explaining variability. However, contrasts between small-scale, kin-based rural subsistence societies and large-scale urban, market-based populations, have not been well appreciated. Nor has the variability within high-income countries, or the socioeconomic and cultural transformations affecting even the most remote tribal populations today. Elucidating the causes and effects of such broad changes on psychology and behavior is a fundamental concern of the social sciences; expanding study participants beyond students and other convenience samples is necessary to improve understanding of flexible psychological reaction norms among and within populations. Here I highlight two examples demonstrating how socioecological variability can help explain psychological trait expression: (i) the role of environmental harshness and unpredictability on shaping time preference and related traits, such as impulsivity, vigilance, and self-efficacy; and (ii) the effects of industrialization, market integration, and niche complexity on personality structure. These cases illustrate how appropriate theory can be a powerful tool to help determine choices of diverse study populations and improve the social sciences.

Social hierarchies occur across human societies, so all humans must navigate them. Infants can detect when one individual outranks another1-3, but it is unknown whether they approach others based on their social status. This paper presents a series of seven experiments investigating whether toddlers prefer high- or low-ranking individuals. Toddlers aged 21-31 months watched a zero-sum, right-of-way conflict between two puppets, in which one puppet 'won' because the other yielded the way. Of the 23 toddlers who participated, 20 reached for the puppet that 'won'. However, when one puppet used force and knocked the other puppet down in order to win, 18 out of 22 toddlers reached for the puppet that 'lost'. Five follow-up experiments ruled out alternative explanations for these results. The findings suggest that humans, from a very early age, not only recognize relative status but also incorporate status into their decisions about whether to approach or avoid others, in a way that differs from our nearest primate relatives4.

The perceived support of supernatural agents has been historically, ethnographically, and theoretically linked with confidence in engaging in violent intergroup conflict. However, scant experimental investigations of such links have been reported to date, and the extant evidence derives largely from indirect laboratory methods of limited ecological validity. Here, we experimentally tested the hypothesis that perceived supernatural aid would heighten inclinations toward coalitional aggression using a realistic simulated coalitional combat paradigm: competitive team paintball. In a between-subjects design, US paintball players recruited for the study were experimentally primed with thoughts of supernatural support using a guided visualization exercise analogous to prayer, or with a control visualization of a nature scene. The participants then competed in a team paintball battle game modeled after "Capture the Flag." Immediately before and after the battle, participants completed surveys assessing confidence in their coalitional and personal battle performance. Participants assessed their coalition's prospects of victory and performance more positively after visualizing supernatural aid. Participants primed with supernatural support also reported inflated assessments of their own performance. Importantly, however, covarying increases in assessments of their overall coalition's performance accounted for the latter effect. This study provided support for the hypothesis that perceived supernatural support can heighten both prospective confidence in coalitional victory and retrospective confidence in the combat performance of one's team, while highlighting the role of competitive play in evoking the coalitional psychology of intergroup conflict. These results accord with and extend convergent prior findings derived from laboratory paradigms far removed from the experience of combat. Accordingly, the field study approach utilized here shows promise as a method for investigating coalitional battle dynamics in a realistic, experientially immersive manner.

The invasive Argentine ant (Linepithema humile) has become established worldwide in regions with Mediterranean or subtropical climates. The species typically disrupts the balance of natural ecosystems by competitively displacing some native ant species via strong exploitation and interference competition. Here we report that Argentine ants utilize glandular secretions for inter and intra-specific communications during aggressive interactions with a heterospecific competitor, California harvester ant (Pogonomyrmex californicus). Chemical analyses indicated that Argentine ants deploy glandular secretions containing two major volatile iridoids, dolichodial and iridomyrmecin, on the competitor's cuticular surface during aggressive interactions. Bioassays indicated that the glandular secretions function as a defensive allomone, causing high levels of irritation in the heterospecific. Furthermore, the same glandular secretions elicited alarm and attraction of conspecific nestmates, potentially enabling more rapid/coordinated defense by the Argentine ants. Two major volatile constituents of the glandular secretion, dolichodial and iridomyrmecin, were sufficient to elicit these responses in conspecifics (as a mixture or individual compounds). The current study suggests that invasive Argentine ants' superior exploitation and interference competition may rely on the species' effective semiochemical parsimony.

The financial health of enterprises and their continued profitability and competitiveness in the market are influenced considerably by the level of earnings achieved. Enterprises are forced to report the best possible results to demonstrate financial strength and competitiveness and to provide a good accounting for investors and creditors. Thus, the main objective of the study is to investigate whether there is any mutual dependence between corporate financial stability and earnings management. To measure these categories, Altman’s Z score was used to determine the financial health of enterprises, and the Beneish M-score and modified Jones model were applied to detect earnings manipulation. Using the chi-square test, the results revealed a statistically significant dependence between financial distress and earnings manipulation. Then, a multivariate statistical technique of correspondence analysis was applied to the categorical data to find categories of factors that are mutually correspondent. Based on a dataset of 11,105 enterprises operating in the Visegrad countries, the results found that enterprises that are threatened by bankruptcy or located in the gray zone tend to manipulate their earnings to maintain credibility, creditworthiness, and competitiveness. Because the financial health of an enterprise provides a potential incentive for earnings manipulation, state authorities, regulators, and policy-makers may benefit from the findings of the study.

This study is aimed to test a theoretical model of the critical thinking, self-efficacy, and adaptation ability prediction towards competitive behavior, with social comparison as a mediator. Participants comprised 334 active university students in Jakarta, the capital of Indonesia. This study applied a predictive-correlational design, with data obtained using questionnaires and analyzed with Structural Equation Modeling. The analysis indicated that the theoretical model corresponds to empirical data (RMSEA = 0.00, NNFI = 1.00) showing that sample data is an accurate representation of the data that would be present in the population (RMSEA < 0.05, NNFI > 0.90). However, critical thinking ability can not predict competitive behavior as mediated by social comparison. This present study provides a deeper understanding that competition is a complex behavior that involves the dimensions of a person's cognitive, self, and adaptive qualities, that cannot be separated from the social context.

States have long used economic sanctions in response to violations of international law as a strategy to restore order. Increasingly, firms also reject doing business with violators. In response to the war in Ukraine, hundreds of multinational corporations voluntarily withdrew from Russia, even when policymakers were still debating the extent of sanctions. How did firm managers evaluate whether to withdraw from the Russian market? Using a survey experiment with Japanese firm managers conducted three months after the Russian invasion of Ukraine in 2022, we explore how peer effects-information on what other firms are doing in response to the crisis-influence support for withdrawal of business activity with Russia. Our findings show that information about withdrawal by other firms from a diverse set of countries promotes peer conformity that increases support. In contrast, information about ongoing business with Russia by Chinese firms fosters competition that reduces support. Market exposure moderates these reactions, although the concern about peer behavior does not appear to be driven by a reputation mechanism. Our research provides insight into how business actors perceive the strategic interplay of peer influence and market dynamics in the context of geopolitical conflicts., Competing Interests: Competing interests statement:The authors declare no competing interest.

Deciding where to forage must not only account for variations in habitat quality but also where others might forage. Recent studies have suggested that when individuals remember recent foraging outcomes, negative frequency-dependent learning can allow them to avoid resources exploited by others (indirect competition). This process can drive the emergence of consistent differences in resource use (resource partitioning) at the population level. However, indirect cues of competition can be difficult for individuals to sense. Here, we propose that information pooling through collective decision-making-i.e. collective intelligence-can allow populations of group-living animals to more effectively partition resources relative to populations of solitary animals. We test this hypothesis by simulating (i) individuals preferring to forage where they were recently successful and (ii) cohesive groups that choose one resource using a majority rule. While solitary animals can partially avoid indirect competition through negative frequency-dependent learning, resource partitioning is more likely to emerge in populations of group-living animals. Populations of larger groups also better partition resources than populations of smaller groups, especially in environments with more choices. Our results give insight into the value of long- versus short-term memory, home range sizes and the evolution of specialization, optimal group sizes and territoriality. This article is part of the theme issue 'Connected interactions: enriching food web research by spatial and social interactions'.

Competition in sports, unlike cooperation in everyday life, does not involve a single solution because individuals aim to behave unpredictably, thereby preventing others from predicting their actions. This study determined how individuals in court-based sports attempted to control others' unpredictable behaviors, addressing the gap in previous studies regarding the lack of clarity around strategies employed by individuals in competitive situations. We achieved this by applying a switching hybrid dynamics model, considering external inputs to analyze individual behaviors. Consequently, the study indicates that skilled individuals, in contrast to intermediate players, exhibit greater consistency in their behaviors. These skilled individuals lead others to anticipate their consistency and subsequently employ strategies to disrupt these expectations. This strategy exploits the principles of active human inference, implying that competition involves cooperation. This was revealed by an analysis of both human decision-making and behavior in actual matches as discrete and continuous dynamical systems. This interpersonal strategy could assist policymakers in the field of everyday life to enhance competitiveness. This strategy enables policymakers to adopt new policies that promote cooperation with competitors, ultimately increasing competitiveness in various aspects of our daily lives., (© 2024. The Author(s).)

Pressure is an innate feature of competition and stimulates cognitions and emotions that can both reduce and enhance performance. Similarly, teams are ubiquitous in sport and influence their members in various ways. Yet, we know little about the ways in which teams influence their members' responses to pressure, whether they are an added demand, inducing social indispensability and exacerbating the effects of pressure, or a resource, providing shared responsibility and buffering pressure effects. We conducted a field experiment across two samples of skilled handball players (N = 189) to test how outcome interdependence vs. independence influenced athletes' appraisals of task importance and coping prospects, anxiety and excitement, and penalty shooting performance under lower vs. higher situational pressure, and to what extent performance order and teammate skill moderated these effects. We found that pressure increased task importance and emotional intensity yet being part of a team or not made little difference. Descriptively, interdependence did attenuate the increase in anxiety under higher pressure and, if paired with skilled teammates, strengthen the increase in excitement. Yet, weak pressure manipulations, insensitive samples and measures require replication and prohibit conclusive interpretations regarding the influence of teams on members' responses to pressure., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Purpose : We investigated youth volleyball players' perception of affordances for different types of serves. Methods : Participants were separated into Less Experienced ( n  = 13, maximum of 3 years of competitive volleyball experience) and More Experienced ( n  = 11, minimum of 4 years of competitive volleyball experience) groups. In the Sideline Condition, participants were asked to report the narrowest gap, relative to either the left or right sideline, into which they could serve the ball. In the Short Condition, participants were asked to report the narrowest gap, relative to the net, into which they could serve the ball. Participants then attempted to serve into their reported gaps. Results : The proportion of successful serves was greater for the More Experienced group than for the Less Experienced group, but a statistically significant interaction revealed that this was true only when performing sideline serves. As expected, reported servable gaps were larger for the Short Serve condition ( M  = 3.66 m, SD = 0.67 m) than for the Sideline Serve condition ( M  = 1.93 m, SD = 0.71 m), F (1, 22) = 80.45, p  < .001, partial η 2  = 0.79. Conclusions : Our study extends previous work to a different sport (volleyball) and to different sport-specific actions (serving the ball). The finding that perceived minimum servable gap sizes were larger for short serves than for sideline serves is consistent with differences in the constraints operating on the two types of serves in the context of game play.

Dominance hierarchies are known for mitigating conflicts and guiding priority of access to limited resources in gregarious animals. The dominance hierarchy of dairy cows is typically investigated using agonistic interactions, often monitored at the feed bunk right after fresh feed delivery when competition is high, resulting in frequent interactions. Yet, the outcome of agonistic interactions during times of high competition may be more influenced by cows' high valuation of fresh feed than their intrinsic attributes, such that the dominance hierarchy constructed using agonistic interactions under high versus low competition times might differ. We tested how the structure of the dominance hierarchy changes in relation to different levels of competition in a dynamic group of 48 lactating dairy cows over 10 mo, with 6 cows exchanged every 16 d, for a total of 159 cows. Using a validated algorithm, we continuously detected the actor and reactor of replacement behaviors in 30 feed bins as cows competed for feed. We also calculated the percentage of occupied feed bins to characterize competition at the moment of each replacement. These data were combined to create hierarchies using Elo ratings, separately for 25 occupancy levels ranging from 13% to 100%. For each 1% rise in feeder occupancy, hierarchy steepness fell by 2.41 × 10 -3 ± 9.71 × 10 -5 (SE), and the percentage of dyads where both cows replaced each other rose by 0.13% ± 0.01%. At the highest feeder occupancy level in comparison to the lowest one, we observed 7.57% more dyads in which the dominant individual (those that won more interactions at the lowest feeder occupancy) started to lose proportionally more. The magnitude of decrease in the winning rate of the dominant individual in those dyads also got amplified by 1.06 × 10 -3 % ± 1.37 × 10 -4 % (SE) for each 1% increase in feeder occupancy. These findings illustrate how inferred hierarchies vary with competition, with high competition flattening the hierarchy due to increased success of subordinate animals. We suggest that during heightened competition, increased valuation of resources can affect competitive success more than the individual's intrinsic dominance attributes. We recommend against calculating dominance hierarchies based on agonistic interactions during periods of high competition alone, and more generally urge researchers to differentiate agonistic interactions based on context when constructing dominance hierarchies., (The Authors. Published by Elsevier Inc. on behalf of the American Dairy Science Association®. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).)

The Multi-Action Plan model offers an idiosyncratic, sport-specific, and applied framework categorising two peak (Type 1 & 2) and two non-peak performance types (Type 3 & 4). The purpose of the present study was to examine the transitions between these Performance Types across three competition-simulating training judo fights. After videoing three judo fights per participant, we interviewed six high-level judo practitioners (Md age  = 19 years) using video-stimulated recall. While watching their fights, participants indicated which Performance Types they experienced during each fight and, subsequently, discussed their experience with the lead researcher. Findings indicated that participants spent most time in effortful mental states (Type 2 & 3). Additionally, they identified currently not defined states 'between' current typologies, e.g., T2.5. Overall, participants reported more down- than upregulations. Specifically, they described downregulations as mostly uncontrolled and related to fatigue, technical-tactical, or cognitive-emotional transition cues. In contrast, they characterised upregulations as deliberate and proactive mental resets, utilising strategies such as self-talk. Lastly, we discussed our findings in relation to existing literature and offered implications for research and practice., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Background: While most game theoretical models assume that individuals randomly interact with all other group members, strong evidence indicates that individuals tend to preferentially interact with some of them. The position of an individual in a network affects, among other factors related to survival, its predation risk and competitive success. Here I then modified the Hawk-Dove game to explore the effect of social network structure on competitive strategy of individuals that differ in their fighting ability and may adjust their use of the Hawk, Dove and Assessor tactics to maximize their foraging success when they meet opponents they are connected with., Results: From randomly generated networks, I demonstrate that phenotypic assortment by fighting ability reduces individuals' aggressiveness and, as such, favours cooperative interactions. Furthermore, the success of individuals with the weakest fighting ability is usually highest within networks where they most frequently meet opponents with the same fighting ability as their own, suggesting they might benefit from breaking connections with strong contestants. This might be the case when strong contestants systematically rely on the aggressive Hawk tactic or the risk of being predated is low and independent of the number of neighbours. Thus, I extended the model and built a dynamic model to allow individuals not only to adjust their behaviour to local conditions but also to modify the structure of the social network. The number of connections and degree of phenotypic assortment are then affected by ecological factors (e.g. resources value and predation risk), but above all by whether individuals can reliably assess the competitive ability of their opponents and adjust their behaviour accordingly., Conclusions: These findings provide strong evidence that behaviour can play a key role in shaping network structure and highlight the importance of considering the coevolution of network and behaviour to apprehend its consequences on population dynamics., (© 2024. The Author(s).)

Drawing from the conservation of resources theory, this study proposes that individuals who perceive environmental competitiveness may improve their mental health through their job crafting behaviors at work. Data were collected from 450 full-time Chinese employees using a three-wave time-lagged approach. The results showed that perceived environmental competitiveness is positively correlated with job crafting, and job crafting has a positive relationship with mental health. Moreover, the results indicated that job crafting mediates the relationship between perceived environmental competitiveness and mental health. Additionally, the present study found that work-family conflict plays a moderating role in the relationships among environmental competitiveness, job crafting and mental health. A moderated mediation model was proposed in this study. Finally, theoretical and practical implications of this study are also discussed., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Cheng and Wang.)

This paper examined the psychological impact of contextual influences (i.e., contract type and playing experience) on sport anxiety in elite women cricketers participating in The Hundred. A sample of 71 elite female cricketers playing during the 2021-2022 season took part. Forty-nine of the sample (69%) held professional contracts, and 22 (31%) had yet to sign a professional contract. Participants provided details about their contract type and playing experience and completed self-report measures assessing sport anxiety, mental toughness, and general self-efficacy. Since mental toughness and self-efficacy are non-cognitive constructs, which buffer competitive trait anxiety, analysis controlled for these variables. Multivariate analyses of covariance examined sport anxiety scores among participants in relation to Hundred matches played (either 0, 1-10, or more than 10) and contract type (whether participants had a professional contract in place or not). Subfactors of Worry, Somatic, and Confusion assessed sports anxiety. No significant main effects existed. However, alongside a significant interaction, a covariate mental toughness effect occurred. Examination of the interaction revealed Worry scores were lower in cricketers who were yet to play a Hundred match who had not received a professional contract. Furthermore, Worry and Somatic scores were higher in cricketers that had played more than 10 Hundred matches and had not received a professional contract. These findings have important implications for the development of elite women cricketers. Particularly, they highlight the need to differentially support players through their career progression., Competing Interests: The authors have declared that no competing interests exist, (Copyright: © 2024 Cross et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

It is widely known controversies about the results of violent video game increase aggression. However, the role of competitive video games, has received less research attention, and the underlying mechanisms of their influence are unknown. This study aimed to expand the existing literature by systematically exploring the effects of competitive video game exposure on adolescent aggression and the mediating role of impulsivity. In so doing, three types of studies (collectively N = 2919, mean age varied from 13.75 to 15.44 years, with a balanced gender) combining cross-sectional, experimental, and longitudinal approaches, were conducted. The findings consistently show that competitive video game exposure increased adolescents' aggression and impulsivity. Also, impulsivity mediated the correlation and long-term effect of competitive video game exposure on aggression. However, the experimental study did not confirm the short-term mediating effect of impulsivity, which may be related to the type of aggression measured in the study. The results indicate that competitive video game exposure is an important antecedent factor for adolescent aggression, and impulsivity is the key underlying mechanism., (© 2024. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Our aim in the present study was to test the efficacy of a 13-week, 19-session psychological intervention program on young soccer players' competitive anxiety and their sport psychological profiles. Participants were 37 players in the under-15 age category, of which 18 players formed the experimental group ( M age = 14.67 years, SD = .48) and 19 players formed the control group ( M age = 14.23 years, SD = .42); this was a quasi-experimental design without random assignment to groups. We had all participants complete the Psychological Inventory of Sport Performance (IPED), the Questionnaire of Psychological Characteristics of Sport Performance (CPRD), and the Competition State Anxiety Inventory-2 (CSAI-2) before and after the intervention. Results indicated positive effects for the intervention group (but not the control group) on stress control and motivation dimensions of the CPRD, cognitive anxiety and self-confidence on the CSAI-2, and self-confidence and attentional control on the IPED. These results suggest that psychological training for athletes contributes to their improved psychological skills, providing them tools to better adapt to the competitive environment., Competing Interests: Declaration of Conflicting InterestsThe author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

The Association of Ringside Physicians (ARP) is committed to the concept of fair competition. It advocates for two equally skilled and matched athletes to keep bouts fair, competitive, entertaining, and, most importantly, safe for all combatants. Numerous studies have proven that transgender women may have a competitive athletic advantage against otherwise matched cis-gender women. Likewise, transgender men may suffer a competitive disadvantage against cis-gender men. These differences - both anatomic and physiologic - persist despite normalization of sex hormone levels and create disparities in competitive abilities that are not compatible with the spirit of fair competition. More importantly, allowing transgender athletes to compete against cisgender athletes in combat sports, which already involve significant risk of serious injury, unnecessarily raises the risk of injury due to these differences. Hence the ARP does not support transgender athlete competition against cisgender athletes in combat sports.

Intraspecific variation in vertebrate eye size is well known. Ecological factors such as light availability are often correlated with shifts in relative eye size. However, experimental tests of selection on eye size are lacking. Trinidadian killifish (Anablepsoides hartii) are found in sites that differ in predation intensity. Sites that lack predators are characterized by lower light, high killifish densities, low resource availability, and intense competition for food. We previously found that killifish in sites that lack predators have evolved a larger "relative" eye size (eye size corrected for body size) than fish from sites with predators. Here, we used transplant experiments to test how selection operates on eye size when fish that are adapted to sites with predators are translocated into sites where predators are absent. We observed a significant "population × relative eye size" interaction; the relationship between relative eye size and a proxy for fitness (rates of individual growth) was positive in the transplanted fish. The trend was the opposite for resident fish. Such results provide experimental support that larger eyes enhance fitness and are favoured in environments characterized by low light and high competition., (© The Author(s) 2024. Published by Oxford University Press on behalf of the European Society of Evolutionary Biology. All rights reserved. For commercial re-use, please contact reprints@oup.com for reprints and translation rights for reprints. All other permissions can be obtained through our RightsLink service via the Permissions link on the article page on our site—for further information please contact journals.permissions@oup.com.)

Learning is a taxonomically widespread process by which animals change their behavioural responses to stimuli as a result of experience. In this way, it plays a crucial role in the development of individual behaviour and underpins substantial phenotypic variation within populations. Nevertheless, the impact of learning in social contexts on evolutionary change is not well understood. Here, we develop game theoretical models of competition for resources in small groups (e.g. producer-scrounger and hawk-dove games) in which actions are controlled by reinforcement learning and show that biases in the subjective valuation of different actions readily evolve. Moreover, in many cases, the convergence stable levels of bias exist at fitness minima and therefore lead to disruptive selection on learning rules and, potentially, to the evolution of genetic polymorphisms. Thus, we show how reinforcement learning in social contexts can be a driver of evolutionary diversification. In addition, we consider the evolution of ability in our games, showing that learning can also drive disruptive selection on the ability to perform a task.

Interspecific competition is an important factor in the population dynamics and geographical distribution of insect populations. Fall armyworm (FAW), Spodoptera frugiperda, an invasive species, and the Asian corn borer (ACB), Ostrinia furnacalis, a native pest species are major pests on maize in China, posing a threat to maize yield and grain quality. A series of laboratory, greenhouse, and field experiments were conducted to elucidate the competitive interactions between FAW and ACB. In the laboratory experiments, FAW exhibited aggressive behaviors more frequently when compared with ACB, while the latter species exhibited defense behaviors more frequently. Higher intraspecific competition was recorded in the FAW conspecific rather than in ACB, particularly in the 6th larval stage. FAW had a higher interspecific competitive advantage through intraguild predation over ACB, resulting in partial or complete displacement ACB when initially the ratio of the 2 species was 1 : 1. The interspecific competition also had significantly influenced on the population parameters, defensive enzymes, and nutrient of these 2 species. Competitive interaction proved that the response of superoxide, catalase, and soluble protein in FAW were significantly increased, whereas the total sugar content in both species was substantially decreased. Survival rate, and the plant damage that co-infested by both species varied significantly among the sequential combinations under greenhouse and field conditions. FAW consistently exhibited stronger intraspecific aggression than ACB under laboratory and field conditions when co-existing on the same feeding guild. These findings contribute to efforts toward the improvement of integrated pest management programs for FAW, in decision making for invasive and native pests' management strategies to reduce the high risks of FAW and ACB outbreaks., (© 2023 Institute of Zoology, Chinese Academy of Sciences.)

The hypothesis that species' ranges are limited by interspecific competition has motivated decades of debate, but a general answer remains elusive. Here we test this hypothesis for lowland tropical birds by examining species' precipitation niche breadths. We focus on precipitation because it-not temperature-is the dominant climate variable that shapes the biota of the lowland tropics. We used 3.6 million fine-scale citizen science records from eBird to measure species' precipitation niche breadths in 19 different regions across the globe. Consistent with the predictions of the interspecific competition hypothesis, multiple lines of evidence show that species have narrower precipitation niches in regions with more species. This means species inhabit more specialized precipitation niches in species-rich regions. We predict this niche specialization should make tropical species in high diversity regions disproportionately vulnerable to changes in precipitation regimes; preliminary empirical evidence is consistent with this prediction., (© 2024 John Wiley & Sons Ltd.)

Marine predators often aggregate at the air-sea boundary layer to pursue shared prey. In such scenarios, seabirds are likely to benefit from underwater predators herding fish schools into tight clusters thereby enhancing seabirds' prey detectability and capture potential. However, this coexistence can lead to competition, affecting not only immediate foraging strategies but also their distribution and interspecies dynamics. We investigated both the longitudinal relationships and instantaneous interactions between streaked shearwaters ( Calonectris leucomelas ) and common dolphinfish ( Coryphaena hippurus ), both preying on Japanese anchovy ( Engraulis japonicus ). Using GPS data from 2011 to 2021, we calculated behavioural parameters for streaked shearwaters as an index of time spent and distance travelled. Despite the abundance of Japanese anchovies, we found that streaked shearwaters might increase their foraging time in the presence of underwater predators. Moreover, video loggers provided direct evidence of streaked shearwaters and common dolphinfish attacking the same fish schools, potentially interfering with bird foraging by dolphinfish. Our results suggest that the presence of underwater predators in a given patch might increase the time spent by seabirds foraging without affecting the distance travelled. This highlights the need for future studies that consider the potential adverse effects of other top predators on seabird prey availability.

Indirect aggression is commonly used in adulthood, but most researchers have focused on this behavior in romantic relationships or from an intrasexual competition perspective. Therefore, we aimed to understand the social characteristics and mental health correlates of indirect aggression by combining perspectives from developmental psychopathology and evolutionary psychology. We examined: (1) whether social characteristics (social comparison, hypercompetitiveness) contributed to indirect aggression (perpetration, victimization) and (2) whether there were indirect effects from indirect aggression (perpetration, victimization) to mental health difficulties through loneliness. In a cross-sectional sample of 475 young adults (57.7% women, 51.6% White, M age  = 20.2, SD age  = 2.18), path analyses revealed that social comparison predicted indirect aggression victimization, which indirectly predicted mental health difficulties (depression, anxiety, somatic symptoms) through loneliness. In contrast, indirect aggression perpetration was only predicted by hypercompetitiveness. The findings highlight that reframing cognitions associated with social comparison could help prevent indirect aggression and mental health difficulties among young people., (© 2024 The Author(s). Aggressive Behavior published by Wiley Periodicals LLC.)

Our purpose in this study was to investigate the relationship between self-efficacy, fear of failure, competitive state anxiety, and flow among elite golfers. We surveyed 375 elite golfers ( N = 375; male = 187, female = 188) who were registered with the Korean Sports and Olympic Committee, and we analyzed their survey responses using descriptive statistics, confirmatory factor analysis, correlation analysis, and structural equation modelling. As expected, we found golf self-efficacy (GSE) to be significantly related to fear of failure (FOF). We also found FOF and competitive state anxiety (CSA) significantly related to flow. Finally, we verified a suspected hierarchical or mediating effect in these relationships such that we verified predictive relationships of flow as follows: GSE→FOF→CSA→Flow. These golfers' self-efficacy had a buffering effect of lowering their FOF and CSA in the pathway toward flow. A suggested implication of these findings is that to enhance a golfer's performance by minimizing interfering psychological factors, it is essential to boost their self-efficacy., Competing Interests: Declaration of conflicting interestsThe author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Background: Effective interprofessional teamwork is essential for the efficiency, safety and quality of healthcare system services and requires interprofessional education for medical students. Physical education is a simple and easy way to teach teamwork, which translates into team performance in the work environment. This study was conducted to examine the effectiveness of the physical education competition model, instead of the exams model, for improving teamwork skills among medical students., Methods: A quasiexperimental intervention design was used to measure the effect of a 16-week cheerleading programme on subjects' teamwork skills by completing a teamwork scale comprising four subdimensions, namely, personal characteristics, teamwork, leadership, and conflict management, before the start and at the end of the programme, and by comparing nonwinning to winning students to measure the effect of teamwork skills on team performance., Results: A total of 179 students completed the valid baseline and posttest (effective rate = 95.21%). The teamwork scale scores (B M = 4.81, R M = 5.05, p < 0.001) and 4 subdimension scores (personal characteristics p = 0.002, teamwork p = 0.028, leadership p < 0.001, conflict management p < 0.001) were statistically significant. Twenty-two of the 44 items in the scale improved significantly. The differences between students who won the competition and those who did not (N M=4.86, W M=5.14, p<0.01) were statistically significant, with no significant differences in personal characteristics p = 0.183; significant differences in the 3 subdimensions of teamwork p < 0.01, leadership p = 0.024, and conflict management p = 0.037; and a significant increase in 13 out of 44 self-efficacy items on the scale., Conclusions: The "race for exams" physical education programme improved teamwork among medical students, and increased teamwork improved team performance. The "competition instead of examination" physical education programme provides a quantifiable method for improving interprofessional teamwork among medical students., (© 2024. The Author(s).)

Background: In the cognitive-affective model of athlete burnout, anxiety is a key physiological response to stress that influences the development of burnout in athletes. Despite its importance, there has been little research on the relationship between competitive anxiety and athlete burnout, particularly regarding the mediating mechanisms. This study aimed to explore the relationship between competitive anxiety and athlete burnout, with a focus on the mediating role of general need satisfaction from self-determination theory., Methods: The current study employed a cross-sectional design involving 618 college athletes (354 females, mean age 20.57 years), comprising 303 participants in individual sports and 315 in team sports. These participants completed the Sport Anxiety Scale-2 (SAS-2), the Athlete Burnout Questionnaire (ABQ), and the Basic Psychological Need Satisfaction Scale in General (BPNSS-G) online. Subsequently, correlation, regression, and mediation analyses were conducted using SPSS and JASP to examine the relationships between the variables., Results: Regression results indicated that somatic anxiety (beta = 0.116, t = 2.21, p = 0.028) and concentration disruption (beta = 0.259, t = 5.35, p < 0.001) in competitive anxiety were positively correlated with athlete burnout. Worry in competitive anxiety was negatively correlated with competence (beta =-0.149, t=-2.70, p = 0.007) and autonomy (beta =-0.179, t=-3.25, p = 0.001) in needs satisfaction. Additionally, the regression results found that competence (beta =-0.178, t=-3.39, p = 0.001) and Autonomy (beta =-0.208, t=-4.17, p < 0.001) were negatively associated with athlete burnout. Mediation analyses revealed significant direct effects in the relationship between somatic anxiety (Effect = 0.116, p = 0.026) along with concentration disruption (Effect = 0.259, p < 0.001) and athlete burnout. In the indirect effect, worry (Effect = 0.071, p = 0.002) as well as concentration disruption (Effect = 0.082, p < 0.001) had significant effects in relation to athlete burnout, respectively., Conclusions: Overall, the current study found that somatic anxiety and concentration disruption in competitive anxiety are related to athlete burnout. Moreover, competence and autonomy in need satisfaction mediated the relationship between competitive anxiety (worry and concentration disruption) and athlete burnout. The findings of this study not only shed further light on the relationship between competitive anxiety and athlete burnout but also provide theoretical insights into the mediating mechanisms of this relationship., (© 2024. The Author(s).)

This study aims to identify contextual situations (score, game time, the interaction between teammates and opponents, start and restart plays) that increase the odds ratio of maintenance of ball possession and scoring a goal. Twenty professional futsal players were evaluated in seven home official matches. The games were filmed to analyze the offensive actions. In total, 828 attacking plays were analyzed. The absence of defensive pressure from the opponent resulted in a greater odds ratio (OR) for loss of ball possession (OR = 1.7, 95% CI = 1.7 to 2.2), but also increased total effectiveness (OR = 6.5; 95%CI = 2.2 to 19.5). The received fouls did not increase the total effectiveness (OR = 0.2; 95%CI = 0.01 to 4.2; p = 0.40). The court regions close to the opponent's goal area and areas where there was less defensive pressure had a higher frequency of goals ( p < 0.05). The results demonstrated that shooting close to opponents' areas and having no defensive pressure were the situations with increased odds of goal-scoring. Maintaining ball possession per se did not increase the OR of goal scoring, however situations when shootings were performed with low defensive pressure could increase chances of goal scoring.

Grounded in Self-Determination Theory, this game-to-game study among Flemish volleyball coaches and athletes had two primary objectives. First, we examined how variations in need-supportive and need-thwarting coaching styles related to variations in athletes' basic psychological needs, motivation, and coach-rated performance. Second, we examined whether athletes who perceived their coach as need-thwarting during a specific game would experience different outcomes based on the overall need-supportive or need-thwarting coaching style they encountered across games. Linear mixed modeling on data from 190 elite volleyball athletes (M age  = 23.95, 32.6 % male) and their 26 coaches (M age  = 48.12, 95.7 % male) indicated positive associations between game-specific need-supportive coaching and athletes' reports of game-specific basic psychological need experiences and motivation, as well as coach-rated performance, whereas game-specific need-thwarting coaching showed opposite trends. Athlete perceptions of a coaching style were more predictive of the outcomes than coach perceptions. Second, the lack of systematic cross-level interactions between game-specific coaching and team-level coaching indicated that the observed correlates of game-specific need-thwarting and need-supportive coaching hold regardless of the perceived overall need-thwarting or need-supportive style of the coach across games., Competing Interests: Declaration of competing interest The authors have no relevant financial or non-financial interests to disclose., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

The tackle contest is the most common and most injurious match contact event in rugby and is an indicator of performance. Tackle Ready is World Rugby's tackle technique education program. Limited research has characterized the tackle contest in women's rugby. The purpose of this study is to: (1) identify the match situational characteristics, ball-carrier and tackler technical actions demonstrated in elite women's Rugby Union and (2) to determine the extent to which Tackle Ready recommended tackle techniques were exhibited. Technical characteristics for 1500 tackle events in the 2022-2023 Women's Six Nations Championship were visually assessed according to a predefined coding framework and the Tackle Ready program. Tackles lacked full completion (0.2%) of the 22 coded Tackle Ready techniques with 47% of the recommended techniques demonstrated in each tackle on average (range 15%-98%). A high proportion of tackles involved two defenders (48%), approaching ball-carriers from the side (38%) or oblique angles (39%), in an upright position (30%), and with initial contact made with the arm (51%). Incorrect pre-contact head positioning and head placement upon contact accounted for 50% and 15% of tackles, respectively, and there was a mean of 14 (95% CI 11-18) head and neck contacts to a tackler and 18 (95% CI 14-22) head and neck contacts to a ball-carrier per game. Targeted interventions to encourage adoption of recommended techniques are needed to reduce tackle-related injury risk in women's rugby. This study provides valuable context for future discussion across law enforcement, coach education and gender-specific tackle coaching in the women's game., (© 2024 The Authors. European Journal of Sport Science published by Wiley‐VCH GmbH on behalf of European College of Sport Science.)

AbstractIntransitive competition has received much attention over the past decade. Indeed, these cyclic arrangements of species interactions have the potential to promote and stabilize species coexistence. However, the importance of intransitive interactions in real-world species-rich communities containing a mixture of hierarchic and intransitive interactions remains unknown. Here, using simulations, we explore the behavior of intransitive loops when they interact with outer competitors, as would be expected in real-world communities. Our results show that dominant competitors often cancel the beneficial effects of intransitive loops of inferior competitors. These results call for caution when inferring beneficial effects of intransitivity on species coexistence. Although intransitive loops are a frequent motif in competition networks, their positive effects on species coexistence may be less important than previously thought. The specific properties of a subnetwork-such as stabilization by intransitive loops-should thus not be interpreted independently of the global network.

Background: Wheelchair tennis, a globally popular sport, features a professional tour spanning 40 countries and over 160 tournaments. Despite its widespread appeal, information about the physical demands of wheelchair tennis is scattered across various studies, necessitating a comprehensive systematic review to synthesise available data., Objective: The aim was to provide a detailed synthesis of the physical demands associated with wheelchair tennis, encompassing diverse factors such as court surfaces, performance levels, sport classes, and sexes., Methods: We conducted comprehensive searches in the PubMed, Embase, CINAHL, and SPORTDiscus databases, covering articles from inception to March 1, 2023. Forward and backward citation tracking from the included articles was carried out using Scopus, and we established eligibility criteria following the Population, Exposure, Comparison, Outcome, and Study design (PECOS) framework. Our study focused on wheelchair tennis players participating at regional, national, or international levels, including both juniors and adults, and open and quad players. We analysed singles and doubles matches and considered sex (male, female), sport class (open, quad), and court surface type (hard, clay, grass) as key comparative points. The outcomes of interest encompassed play duration, on-court movement, stroke performance, and physiological match variables. The selected study designs included observational cross-sectional, longitudinal, and intervention studies (baseline data only). We calculated pooled means or mean differences with 95% confidence intervals (CIs) and employed a random-effects meta-analysis with robust variance estimation. We assessed heterogeneity using Cochrane Q and 95% prediction intervals., Results: Our literature search retrieved 643 records, with 24 articles meeting our inclusion criteria. Most available information focused on international male wheelchair tennis players in the open division, primarily competing in singles on hard courts. Key findings (mean [95% CI]) for these players on hard courts were match duration 65.9 min [55.0-78.8], set duration 35.0 min [28.2-43.5], game duration 4.6 min [0.92-23.3], rally duration 6.1 s [3.7-10.2], effective playing time 19.8% [18.9-20.7], and work-to-rest ratio 1:4.1 [1:3.7-1:4.4]. Insufficient data were available to analyse play duration for female players. However, for the available data on hard court matches, the average set duration was 34.8 min [32.5-37.2]. International male players on hard court covered an average distance per match of 3859 m [1917-7768], with mean and peak average forward speeds of 1.06 m/s [0.85-1.32] and 3.55 m/s [2.92-4.31], respectively. These players executed an average of 365.9 [317.2-422.1] strokes per match, 200.6 [134.7-299.0] per set, 25.4 [16.7-38.7] per game, and 3.4 [2.6-4.6] per rally. Insufficient data were available for a meta-analysis of female players' on-court movement and stroke performance. The average and peak heart rates of international male players on hard court were 134.3 [124.2-145.1] and 166.0 [132.7-207.6] beats per minute, and the average match heart rate expressed as a percentage of peak heart rate was 74.7% [46.4-100]. We found no studies concerning regional players or juniors, and only one study on doubles match play., Conclusions: While we present a comprehensive overview of the physical demands of wheelchair tennis, our understanding predominantly centres around international male players competing on hard courts in the open division. To attain a more comprehensive insight into the sport's physical requirements, future research should prioritise the inclusion of data on female and quad players, juniors, doubles, and matches played on clay and grass court surfaces. Such endeavours will facilitate the development of more tailored and effective training programmes for wheelchair tennis players and coaches. The protocol for this systematic review was registered a priori at the International Platform of Registered Systematic Review and Meta-analysis Protocols (Registration https://doi.org/10.37766/inplasy2023.3.0060 )., (© 2024. The Author(s), under exclusive licence to Springer Nature Switzerland AG.)

Most studies on deception in soccer penalty kicks have focused on the deceptive actions used by penalty takers. However, it is worth noting that deception can also be played out by goalkeepers. To examine the effectiveness of goalkeepers' deceptive actions in professional competition, we analysed 714 penalty kicks taken during matches in the English Premier League and German Bundesliga, spanning the seasons from 2016-2017 to 2019-2020. We scored whether goalkeepers used deception, and if so, what type of deception, the outcome of the penalty and the kicking strategy of the penalty taker. The results showed that goalkeepers used deception in half of the penalty kicks, resulting in significantly less goals compared to penalties without deception. This advantage was similar for the different types of deception, but larger when penalty takers paid attention to goalkeepers. We propose that the deceptive actions by goalkeepers are effective, mainly because it leads the penalty taker to lose focus. The practical implications of these findings are discussed for both goalkeepers and penalty takers.