The Transfer of Male Cuticular Hydrocarbons Provides a Reliable Cue of the Risk and Intensity of Sperm Competition in Decorated Crickets

Theoretically, males should increase their ejaculate expenditure when the probability of sperm competition occurring (or risk) is high but decrease ejaculate expenditure as the number of competing ejaculates (or intensity) increases. Here we examine whether male decorated crickets (Gryllodes sigillatus) use cuticular hydrocarbons (CHCs) transferred to females by rival males at mating to assess the risk and intensity of sperm competition and adjust their ejaculate accordingly. Unmated females and those perfumed with CHCs extracted from one, three, or five males could be distinguished chemically, providing a reliable cue of the risk and intensity of sperm competition. In agreement with theory, males mating with these females increased sperm number with the risk of sperm competition and decreased sperm number with the intensity of sperm competition. Similarly, as the risk of sperm competition increased, males produced a larger and more attractive spermatophylax (an important non-sperm component of the ejaculate) but these traits did not vary with the intensity of sperm competition. Our results therefore demonstrate that both sperm and non-sperm components of the male ejaculate respond to the risk and intensity of sperm competition in different ways and that CHCs provide males with an important cue to strategically tailor their ejaculate

A description of the profiles of U18 rugby players who attended the Craven Week tournament between 2002-2012

Rugby union has rich tradition in South Africa with the national team having won the Rugby World Cup in 1995 and 2007. The major rugby nations South Africa competes against have clearly defined rugby talent identification (TID) and development (TDE) pathways. These pathways are not as well described in South Africa where the South African Rugby Union (SARU) has adopted a model of identifying talent at an early age through competition. For example, national competitions occur at U13 (Craven Week), U16 (Grant Khomo Week) and U18 (Craven Week and Academy Week) levels. Previous research on talent identification has highlighted the pitfalls of early talent identification. In particular different rates of maturation can influence the manifestation of talent. In a collision sport such as rugby the early maturers have a distinct advantage. An added complexity in the South African context is the need to provide an appropriate development environment within which transformation can take place. At all levels in South African professional rugby, white players dominate team selection. One of the reasons suggested for this dominance is the physical size of white players compared to their black and mixed race (coloured) counterparts. Rugby is a contact sport and physical size is associated with success, so the need to quantify physical difference between racial groups at a junior level over time is important. The first objective of the thesis was to examine the profiles of U18 Craven Week rugby players to gain insight into the development pathway from U13 to U18. A second aim was to understand factors influencing transformation by measuring the physical profiles of the various racial groups over time. The thesis consists of two studies. The specific objective of the first study was quantify how many players in the 2005 U13 Craven Week (n=349) participated in the subsequent U16 Grant Khomo and U18 Craven Week. The study showed that 31.5% of the players who played in the U13 Craven Week, were selected to play at U16 Grant Khomo Week and 24.1% were selected for the U18 Craven Week tournaments. Another interpretation is that 76% of the players selected for the U13 tournament did not play at the U18 Craven Week tournament. The objective of the second study was to determine whether there are differences in body mass, stature and body mass index (BMI) between racial groups in U18 Craven Week players. Another objective was to determine whether these measurements changed between 2002-2012. Self-reported body mass and stature were obtained from U18 players (n=4007) who attended the national tournament during this period. BMI was calculated for each player. The body mass, stature and BMI of these players in South Africa were significantly different between racial groups. For example, white players were 9.8 kg heavier than black players, who were 2.3 kg heavier than coloured players (p<0.0001). The body mass of all groups increased from 2002-2012 (p < 0.0001). White players were 7.0 cm taller than black players, who were 0.5 cm taller than coloured players (p < 0.0001). The stature of players did not change significantly during the study period. The average BMI of white players was 0.9 kg.m⁻² greater than black players who were on average 0.7 kg.m⁻² greater than coloured players (p<0.0001). The BMI of all groups changed similarly over the study period. To conclude, these results question the effectiveness of the u13 tournament in identifying talent and providing an effective development pathway to U18 Craven Week. The SARU also needs to be aware of the ongoing disparities in size between the racial groups playing rugby at an U18 level in South Africa. These size differences may have implications for transforming the game and making it representative of the South African population

Quantifying technical actions in professional soccer using foot-mounted inertial measurement units

This thesis aimed to (i) establish the concurrent validity and intra-unit reliability of a foot-mounted inertial measurement unit (IMU), for measuring the frequency of technical actions performed during soccer training activities, and (ii) to quantify the within-microcycle, inter-positional, and between-drill differences in the technical actions of professional soccer training using foot-mounted IMUs.Twelve male amateur soccer players collectively performed 8,640 ball touches and 5,760 releases, throughout a series of technical soccer tasks, repeated over two pre-determined distances. Concurrent validity was determined by calculating the proportion of agreement (PA) between the IMU and retrospective video analyses. Intra-unit reliability was established using the same method, supplemented by a percentage coefficient of variation (CV). Intra-operator reliability of the reference performance analyst, who conducted all analyses, was established by manually coding three randomly selected repetitions of each soccer task three times (PA = 100.0%). The IMU exhibited good concurrent validity (PA = 95.1% - 100.0%) and intra-unit reliability (PA = 95.9% - 96.9%, CV = 1.4% - 2.9%) for measuring ball touches and releases throughout all experimental conditions.Twenty-one male professional soccer players’ technical performance data (ball touches, releases, ball touches per minute, releases per minute), collected during training sessions throughout 24 weekly microcycles (i.e., match day [MD] minus day number [MD - n]), was subsequently analysed using general linear modelling. The most ball touches (X = 218.0) and releases (X = 110.8) were observed on MD - 1, with MD - 5 eliciting the highest frequency of ball touches per minute (X = 3.8) and releases per minute (X = 1.7). Central midfielders performed the most ball touches (X = 221.9), releases (X = 108.3), ball touches per minute (X = 3.4), and releases per minute (X = 1.6). Small-sided games evoked more ball touches per minute (Xdiff = 1.5), and releases per minute (Xdiff = 0.1), than previously reported in match-play. The fewest ball touches per minute (X = 1.2) and releases per minute (X = 0.5) were observed during tactical drills. The results of this thesis indicate that the foot-mounted IMU displayed promising capacity as a valid and reliable method of quantifying technical actions in soccer, as well as providing a novel understanding of the within-microcycle, inter-positional, and between-drill differences in the technical actions performed by professional players during training

TRACKING FORMATION CHANGES AND ITS EFFECTS ON SOCCER USING POSITION DATA

This study investigated the application of advanced machine learning methods, specifically k-means clustering, k-Nearest Neighbors (kNN), and Support Vector Machines (SVM), to analyze player tracking data in soccer. The primary hypothesis posits that such data can yield a standalone, in-depth understanding of soccer matches. The study revealed that while k-means and spatial analysis are promising in analyzing player positions, kNN and SVM show limitations without additional variables. Spatial analysis examined each team’s convex hull and studied the correlation between team length, width, and surface area. Results showed team length and surface area have a strong positive correlation with a value of 0.8954. This suggested that teams with longer team length have a more direct style of play with players more spread out which led to larger surface areas. k-means clustering was performed with different k values derived from different approaches. The silhouette method recommended a k value of 2 and the elbow recommended a k value of 4. The context of the sport suggested additional analysis with a k value of 11. The results from k-means suggested natural data partitions, highlighting distinct player roles and field positions. kNN was performed to find similar players with the model of k = 19 showing the highest accuracy of 8.61%. The SVM model returned a classification of 55 classes which indicated a highly granular level of categorization for player roles. The results from kNN and SVM indicated the necessity of further contextual data for more effective analysis and emphasized the need for balanced datasets and careful model evaluation to avoid biases and ensure practical application in real-world scenarios. In conclusion, each algorithm offers unique perspectives and interpretations on player positioning and team formations. These algorithms, when combined with expert knowledge and additional contextual data, can significantly enrich the scope of analysis in soccer. Future work should consider incorporating event data and additional variables to enhance the depth of analytical insights, enabling a more comprehensive understanding of how formations evolve in response to various in-game situations

A CASE STUDY OF SPORTS FEDERATIONS IN UGANDA

학위논문(석사) -- 서울대학교대학원 : 사범대학 체육교육과,글로벌스포츠매니지먼트전공, 2021.8. 힐다.스포츠 산업에서 성 불평등은 오랫동안 논쟁거리가 되어 오고 있다. 심지어 현대 올림픽의 창시자인 피에르 드 쿠베르텡 남작은 1989년에 스포츠에 참여하는 여성이 얼마나 힘든지는 중요하지 않다, 그녀들은 고통을 감내할 줄 모르기 때문이다고 언급하기도 하였다. 1978년에는 유네스코에서 아직 스포츠를 인간의 기초권리로 인정하지 않았으며, 이를 통해서도 아직 스포츠 분야는 갈 길이 멀다고 생각한다. 스포츠계에서 여성들이 직면하는 어려움이 많음에도 불구하고, 많은 여성들이 여성과 남성의 평등한 스포츠 참여에 대한 권리를 쟁취하기 위해서 그 길을 이끌어 나아가고 있다. 여성들 또한 남성들처럼 스포츠 참여를 통해 리더십과 자존감을 향상시키고 신체의 건강을 도모할 수 있어야 한다. 여성과 소녀들의 스포츠 참여는 특히 건강해야 한다. 스포츠는 교육, 건강, 사회적 교류를 위해서 성별과 나이, 능력, 인종, 지역, 정치, 사회 경제적 배경과 관계없이 누구나 참여할 수 있는 공공재여야 한다. 그러나 2012년 런던 하계올림픽만 보아도 대다수의 참여국가들의 대표단이 남성으로 편성되어 있는 현실은 스포츠에서의 성불평등이 여전히 존재한다는 것을 보여준다. 남성과 여성의 생물학적 차이를 근거로 계속해서 성차별이 남아 있다면, 그것은 여성의 참여 기회를 감소시킬 것이다. 나아가 이것은 지속적인 사회 정치적인 요인을 재생산 할 가능성이 높다. 본 연구의 근본적인 목적은 우간다의 스포츠 성과와 생활 스포츠 영역에서의 스포츠 참여의 불평등을 야기하는 근본적인 원인을 파악하고, 나아가 궁극적으로 여성의 엘리트 스포츠 경기 성과와 스포츠 참여에 지속적으로 영향을 미치는 문화적, 사회, 정치적 원인을 고찰하는 것이다. 따라서 아래 3가지 질문에 대한 해답을 구하는 방식으로 연구를 진행하였다. 우간다의 스포츠 지도자와 협회 관리자들은 성 계층화에 대해서 어떤 인식을 가지고 있는가? 여성 스포츠 지도자들은 스포츠 영역에서 양성 평등(인기, 참여, 대중의 관심)이 어떤 수준으로 이뤄져 있다고 인식하고 있는가?스포츠 분야 전체에서 스포츠 리더들의 양성평등을 촉진하기 위한 전략은 무엇인가? 우간다 스포츠 연맹에서부터 스포츠 지도자들의 의견, 아이디어와 경험에 대한 해석과 사례를 질적 연구하였다. 연구주제에 필요한 정보를 수집하기 위해 설문조사를 하였다. 그리고 나서 데이터의 주제별 내용 분석을 하였다. 그 결과는 여성들이 스포츠 리더십에 관여하지 않는 많은 이유들 중, 사회가 여성이 할 수 없다고 생각하기 때문이라는 것을 보여주었다. 게다가, 여성들은 성희롱과 여성의 능력을 증명해야 하는 많은 도전들을 직면해야 하기 때문이다. 그리고 또한, 연구는 연구 인구로부터 성평등을 촉진하기 위한 전략들을 알아낼 수 있었다. 그 중 하나는 동등한 지도력의 공유와 순환 그리고 성(남성/여성)과 관련하여 서로 다르지만 동등한 후보들을 채우는 것이다.Gender inequality in the sports industry has long been a contentious issue—even the founder of the modern Olympics, Baron Pierre de Coubertin, said in 1896, "It doesn't matter how difficult a sportswoman can be, her organism is not cut out in order to sustain those shocks." It was a long journey to acceptance and recognition for women in sport, including the delays to an extent that UNESCO only accepted sport and physical activity as a human right for every human being way back in 1978. Despite the challenges women face in sports, many women have led and are still leading the way. The road to gender equality and women's engagement in sports profits just as it does to men in helping improve leadership skills, enhance self-esteem and grades (boys in school), and encourage physical fitness. Women and girls who participate in sports and fitness activities are healthier. Sport is recognized as having a relevant societal role in promoting education, fitness, intercultural dialog and individual growth, regardless of gender, ethnicity, age, capacity, religion, political affiliation, sexual orientation and socio-economic background. However, it was not until the 2012 London Summer Olympic Games that every country delegation included a female athlete. While the gender gap in sport remains closed due to biological differences affecting results, it is also affected by reduced opportunities and socio-political factors that influence the full participation of women in a wide range of sports around the world. Until the cultural atmosphere is equal, there is minimal scientific discussion of physiological differences using methods that analyze improvement in both male and female world sports records. The goal of this research was to provide an insight to the issues underlying gender and sport inequalities in sport performance and sports participation in general in Uganda and to consider the impact of cultural and socio-political factors that ultimately continue to affect women's performance and Women sports in Uganda. The research had three research questions to look at namely: - What the perception of sports leaders on gender stratification in the leadership and management of sports in Uganda are, How women sports leaders perceive female sports in terms of gender equality measures (i.e., participation, popularity and spectatorship interest) and then what the strategies for promoting gender equality among sports leaders in the entire sports sector are. The study used a Qualitative approach of research method where a case study was conducted to get as well as interpret the opinions, ideas and also experiences of sports leaders in Ugandan Sports Federations. A semi-structured questionnaire was utilized to collect information with regards to the study topic and objectives. The data was then analyzed by way of doing a thematic content analysis. The results showed that among the many reasons why women are not involved in sports leadership is because the society believes that women are not able. Furthermore, women face a lot of challenges like sexual harassment and putting them on spotlight for them to prove their competence as women. And then more also that, the study was able to realize from the population of study some strategies for promoting gender equality. And one among the many is equal sharing and rotation of leadership and having to fill in different and equal candidates with regards to sex (male/female).CHAPTER 1. INTRODUCTION １ 1.1. Background of the study １ 1.2. Problem Statement ３ 1.3. Purpose of the Study ３ 1.4. Research Questions ４ 1.5. Scope of the Study ４ 1.5.1. Geographical scope ４ 1.5.2. Content scope ４ 1.5.3. Time scope ４ 1.5. Significance of the study ５ 1.6. Definitions of Key Terms ５ Chapter 2: Literature Review ５ 2.1. Introduction ５ 2.2. Theories ６ 2.2.1. Theory of Gender Stratification ６ 2.2.2. Sports benefit for Socio Value ８ 2.3. Review of Key Terms １１ 2.3.1. Sports １１ 2.3.2. Gender Stratification １３ 2.4. History of Women's Sport １５ Chapter 3. Method ２４ 3.3.1. Sampling Techniques and Procedures ２５ 3.3.2. Interview Participants Selection Criteria ２６ Chapter 4. Result ３０ 4.1.1. Equal opportunities for both men and women to compete for top leadership positions ３１ 4.1.2. Women given opportunities to participate in sports leadership conferences and workshops ３２ 4.1.3. Women in management position are respected by staff members ３３ 4.1.4. The challenges faced by women in leadership positions ３５ 4.1.5. The challenges faced by women to grow up the career in sports leadership ３７ 4.2.1. The negative cultural prejudices that affect women participation in sports leadership ３８ 4.2.2. Men are more popular in sports activities/sports management in most federations than women ４１ 4.2.3. Community members/sports funs awareness of the influence of women in Sports ４２ 4.3. The Strategies for Promoting Gender Equality among Sports Leaders in the Entire Sports Sector ４４ 4.3.1. The actions taken by the federations in promoting gender equality among sports leaders ４４ 4.3.2. The actions that can be taken to promote women sports leaders ４５ Chapter 5. Discussion, Conclusions and Recommendations ４７ 5.1. Discussion ４７ 5.2. Limitations of the study ４８ 5.3. Conclusion ４９ 5.4. Recommendation ５１ References ５２ APPENDIX 1: INTER`VIEW GUIDE ５７ Appendix 2: Consent Form ６０ Appendix 3: Coded Data ６３ 국문초록 ７８석

The role of conspecific social information on male mating decisions

Tese de doutoramento, Biologia (Etologia), Universidade de Lisboa, Faculdade de Ciências, 2018Behavioural plasticity occurs when animals adjust their behaviour to current environmental conditions. Research suggests that this ability helps animals cope with changeable environments, especially in the social domain, where social information is highly variable and unpredictable. In this thesis I evaluated the contribution of the complexity of social information to: 1) male mating behaviours, 2) evolution of courtship display, and 3) evolution of dishonest communication. For male mating behaviours, I performed experiments with guppies (Poecilia reticulata). I predicted that males would invest more on mating attempts if they spend more time without mating (chapter 2), and when there was a higher probability of mating success or fertilization success (chapters 3 and 4). I found that time between encounters with females (not time between actual mating opportunities) was determinant to male investment. Moreover, males did not avoid encountering competitors but invested more when they were the first to arrive near females (not the last), and when competing against more attractive males (but only for orange colouration). These evidences support that males produce complex plastic responses in face of diverse social information. For the evolution of courtship display and dishonest communication, my hypothesis was that competitor (bystander) males use the courtship performance of other males as information about their competitive ability, and that displayer males adjust their behaviour accordingly. For this, I performed systematic reviews (chapter 5), where I found that male male courtship display is, indeed, frequently associated with intrasexual competition, suggesting that courtship display has evolved a dual utility: attract females and intimidate competitors. A corollary of this, which I developed in a conceptual study (chapter 6), is that males can display dishonestly to deter competitors. If so, the interference of bystanders in communication systems could have a non-negligent role in the evolution of dishonest signalling

Helping the man in the middle: assessing and training referee performance

This thesis describes an applied programme of research with the English Rugby Football Union (RFU) national panel of referees. Referee performance can have a critical impact on the outcomes of games and as a consequence the future status of the clubs & players concerned. Surprisingly, given the importance of referees, access to scientific support for these individuals is almost non-existent. Furthermore, there are only a handful of empirical investigations that have explored refereeing performance and none that has attempted to train sports officials. Accordingly, this programme of research set out to understand, operationalise and train the key aspects of referee performance. Using a multi-modal approach the first investigation used referee performance profiling and content analyses of three sources of literature to establish the key areas of referee performance. The Cornerstones Performance Model of Refereeing emerged, overarched by the psychological characteristics of excellence; featuring knowledge and application of the law; contextual judgment; personality and management skills; and fitness and positioning. The model was subsequently adopted by the RFU to structure the applied support programme and guide the development and selection of the English RFU referees. A naturalistic approach was adopted, focussing primarily on the decision-making aspects of the performance model. A video based, law-application assessment tool revealed surprisingly low levels of accuracy amongst referees and their support groups. Accordingly, a training programme was designed to reinforce accurate and coherent interpretations. A group of national panel referees watched videotaped scenarios taken from premier league games, showing 5 sets of 5 tackles, in each case with an expert providing the interpretation of the correct decision. All referee groups improved their performance from pre to posttest, with the lowest ranked referees showing significant improvements. However, as the performance model presents, referee DM is influenced by many factors beyond a simple application of the law. Accordingly, the final investigation explored the factors that change the game context and how they influence rugby-union referees management of the game. Following the nominal group technique, two groups of referees listed contextual factors that they felt might affect their decisions during a game. Individual ratings of this list with both groups revealed the most important factors to be the "temper of the game," "the level of player respect/rapport," "position on pitch," "scoreline," and the "time left in the game." To verify these factors a think-aloud protocol was conducted with three international referees, assessing how they weigh their decisions based on the context and how this affects their management of the game. The results suggest that elite referees use "preventative refereeing" to help maintain the natural flow to a game. Finally, the implications of this research programme are discussed in the light of expediting the development of high performance referees in open team sports

Physical Preparation in Female Rugby Codes: An Investigation of Current Practices

Female sports have recently seen a dramatic rise in participation and professionalism world-wide. Despite progress, the infrastructure and general sport science provisions in many female sports are behind their male counterparts. From a performance perspective, marked differences in physical and physiological characteristics can be seen between the sexes. Although physical preparation practices for male athletes are known, there are currently no published literature pertaining exclusively to female athletes. This information would provide invaluable data for both the researcher and practitioner alike. This survey therefore aimed to examine current practices utilized in female rugby codes (union, league, and sevens). A questionnaire assessing seasonal physical preparation practices, recovery, monitoring and sport science technology, and unique aspects in female rugby was developed. Thirty-seven physical preparation practitioners (32 males, 5 females) responded to the questionnaire. Most participants (78%) worked with national or regional/state level female athletes. Performance testing was more frequently assessed in the pre- (97%) and in-season (86%), than off-season (23%). Resistance, cardiovascular, sprint and plyometric training, and recovery sessions were all believed to be important to enhancing performance and implemented by most participants (≥ 89%). Sport science technologies were commonly (54%) utilized to inform current practice. Menstrual cycle phase was monitored by 22% of practitioners. The most frequently reported unique considerations in female rugby codes included psycho-social aspects (41%), the menstrual cycle (22%), and physical differences (22%). Practitioners working with female rugby can use the presented data to inform and develop current practices