Vision-based tracking for sports performance analysis

With the world of professional sports shifting towards employing better sport analytics, the demand for vision-based performance analysis is growing increasingly in recent years. In addition, the nature of many sports does not allow the use of any kind of sensors or other wearable markers attached to players for monitoring their performances during competitions. This provides a potential application of systematic observations such as tracking information of the players to help coaches to develop their visual skills and perceptual awareness needed to make decisions about team strategy or training plans. My PhD project is part of a bigger ongoing project between sport scientists and computer scientists involving also industry partners and sports organisations. The overall idea is to investigate the contribution technology can make to the analysis of sports performance on the example of team sports such as rugby, football or hockey. A particular focus is on vision-based tracking, so that information about the location and dynamics of the players can be gained without any additional sensors on the players. To start with, prior approaches on visual tracking are extensively reviewed and analysed. In this thesis, methods to deal with the difficulties in visual tracking to handle the target appearance changes caused by intrinsic (e.g. pose variation) and extrinsic factors, such as occlusion, are proposed. This analysis highlights the importance of the proposed visual tracking algorithms, which reflect these challenges and suggest robust and accurate frameworks to estimate the target state in a complex tracking scenario such as a sports scene, thereby facilitating the tracking process. Next, a framework for continuously tracking multiple targets is proposed. Compared to single target tracking, multi-target tracking such as tracking the players on a sports field, poses additional difficulties, namely data association, which needs to be addressed. Here, the aim is to locate all targets of interest, inferring their trajectories and deciding which observation corresponds to which target trajectory is. In this thesis, an efficient framework is proposed to handle this particular problem, especially in sport scenes, where the players of the same team tend to look similar and exhibit complex interactions and unpredictable movements resulting in matching ambiguity between the players. The presented approach is also evaluated on different sports datasets and shows promising results. Finally, information from the proposed tracking system is utilised as the basic input for further higher level performance analysis such as tactics and team formations, which can help coaches to design a better training plan. Due to the continuous nature of many team sports (e.g. soccer, hockey), it is not straightforward to infer the high-level team behaviours, such as players’ interaction. The proposed framework relies on two distinct levels of performance analysis: low-level performance analysis, such as identifying players positions on the play field, as well as a high-level analysis, where the aim is to estimate the density of player locations or detecting their possible interaction group. The related experiments show the proposed approach can effectively explore this high-level information, which has many potential applications.

Training-related risk of common illnesses in elite swimmers over a 4-yr period

The evolution of imperfect mimicry in hoverflies

Ideas about the evolution of imperfect mimicry are reviewed. Their relevance to the colours patterns of hoverflies (Diptera, Syrphidae) are discussed in detail. Most if not all of the hoverflies labelled as mimetic actually are mimics. The apparently poor nature of their resemblance does not prevent them from obtaining at least some protection from suitably experienced birds. Mimicry is a dominant theme of this very large family of Diptera, with at least a quarter of all species in Europe being mimetic. Hoverfly mimics fall into three major groups according to their models, involving bumblebees, honeybees and social wasps. There are striking differences in the general levels of mimetic fidelity and relative abundances of the three groups, with accurate mimicry, low abundance and polymorphism characterizing the bumblebee mimics: more than half of all the species of bumblebee mimics are polymorphic. Mimics of social wasps tend to be poor mimics, have high relative abundance, and polymorphism is completely absent. Bumblebee models fall into a small number of Muellerian mimicry rings which are very different between the Palaearctic and Nearctic regions. Social wasps and associated models form one large Muellerian complex. Together with honeybees, these complexes probably form real clusters of forms as perceived by many birds. All three groups of syrphid mimics contain both good and poor mimics; some mimics are remarkably accurate, and have close morphological and behavioural resemblance. At least some apparently 'poor' mimetic resemblances may be much closer in birds' perception than we imagine, and more work needs to be done on this. Bumblebees are the least noxious and wasps the most noxious of the three main model groups. The basis of noxiousness is different, with bumblebees being classified as non-food, whereas honeybees and wasps are nasty-tasting and (rarely) stinging. The distribution of mimicry is exactly what would be expected from this ordering, with polymorphic and accurate forms being a key feature of mimics of the least noxious models, while highly noxious models have poor-quality mimicry. Even if the high abundance of many syrphid mimics relative to their models is a recent artefact of man-made environmental change, this does not preclude these species from being mimics. It seems unlikely that bird predation actually controls the populations of adult syrphids. Being rare relative to a model may have promoted or accelerated the evolution of perfect mimicry: theoretically this might account for the pattern of rare good mimics and abundant poor ones, but the idea is intrinsically unlikely. Many mimics seem to have hour-to-hour abundances related to those of their models, presumably as a result of behavioural convergence. We need to know much more about the psychology of birds as predators. There are at least four processes that need elucidating: (a) learning about the noxiousness of models; (b) the erasing of that learning through contact with mimics (extinction, or learned forgetting); (c) forgetting; (d) deliberate risk-taking and the physiological states that promote it. Johnston's (2002) model of the stabilization of imperfect mimicry by kin selection is unlikely to account for the colour patterns of hoverflies. Sherratt's (2002) model of the influence of multiple models potentially accounts for all the patterns of hoverfly mimicry, and is the most promising avenue for testing.

Jung and Goddess: the significance of Jungian and post-Jungian theory to the development of the Western Goddess Movement

This study is concerned with the significance of Jungian and post-Jungian theory to the development of the contemporary Western Goddess Movement, which includes the various self-identified nature-based, Pagan, Goddess Feminism, Goddess Consciousness, Goddess Spirituality, Wicca, and Goddess-centred faith traditions that have seen a combined increase in Western adherents over the past five decades and share a common goal to claim Goddess as an active part of Western consciousness and faith traditions. The Western Goddess Movement has been strongly influenced by Jung’s thought, and by feminist revisions of Jungian Theory, sometimes interpreted idiosyncratically, but presented as a route to personal and spiritual transformation. The analysis examines ways in which women encounter Goddess through a process of Jungian Individuation and traces the development of Jungian and post-Jungian theories by identifying the key thinkers and central ideas that helped to shape the development of the Western Goddess Movement. It does so through a close reading and analysis of five biographical ‘rebirth’ memoirs published between 1981 and 1998: Christine Downing’s (1981) The Goddess: Mythological Images of the Feminine; Jean Shinoda Bolen’s (1994) Crossing to Avalon: A Woman’s Midlife Pilgrimage; Sue Monk Kidd’s (1996) The Dance of the Dissident Daughter: A Woman’s Journey from Christian Tradition to the Sacred Feminine; Margaret Starbird’s (1998) The Goddess in the Gospels: Reclaiming the Sacred Feminine; and Phyllis Curott’s (1998) Book of Shadows: A Modern Woman’s Journey into the Wisdom of Witchcraft and the Magic of the Goddess. These five memoirs reflect the diversity of the faith traditions in the Western Goddess Movement. The enquiry centres upon two parallel and complementary research threads: 1) critically examining the content of the memoirs in order to determine their contribution to the development of the Goddess Movement and 2) charting and sourcing the development of the major Jungian and post-Jungian theories championed in the memoirs in order to evaluate the significance of Jungian and post-Jungian thought in the Movement. The aim of this study was to gain a better understanding of the original research question: what is the significance of Jungian and post-Jungian theory for the development of the Western Goddess Movement? Each memoir is subjected to critical review of its intended audiences, its achievements, its functions and strengths, and its theoretical frameworks. Research results offered more than the experiences of five Western women, it also provided evidence to analyse the significance of Jungian and post-Jungian theory to the development of the Western Goddess Movement. The findings demonstrate the vital contributions of the analytical psychology of Carl Jung, and post-Jungians M Esther Harding, Erich Neumann, Christine Downing, E.C. Whitmont, and Jean Shinoda Bolen; the additional contributions of Sue Monk Kidd, Margaret Starbird, and Phyllis Curott, and exhibit Jungian and post-Jungian pathways to Goddess. Through a variety of approaches to Jungian categories, these memoirs constitute a literature of Individuation for the Western Goddess Movement.

Sports sponsorship as a channel for brand engagement on social media

The purpose of this Mater’s Thesis was to examine how sports sponsorship can be used as a channel for brand engagement on social media. All these three concepts have been researched previously, however, up until now they have been studied separately. Therefore, the aim was also to investigate the interrelations between these three concepts, as there is a lack of academic base on the matter. The theory of the research was based on existing academic researches of social media, brand engagement and sports sponsorship. The empirical part of the research was conducted by utilizing quantitative research method. An online questionnaire was published on Facebook pages of two Liiga ice hockey teams. In the end the total sample consisted of 322 viable respondents. The collected data was analyzed by using statistical analysis software, SPSS. The findings of the empirical research reveal that information, enjoyment, personal identity, social interaction and compensation motivate consumers to engage with brands on social media. However, the behavior of consumers is more passive than active brand engagement. Personal identity and compensation serve as motivational reasons for brand engagement on both active and passive level, while the rest are only passive brand engagement. Besides motivation there are other variables that affect consumers. Support for the team reflects to brand engagement, which is passive brand engagement. The visibility of the brand during the event is linked to both active and passive brand engagement. Prior information of sports team and event and frequency of attendance can be linked only to active brand engagement. On the other hand, congruence between the team and brand reflects only to passive brand engagement.

Effects of acute exercise on salivary free insulin-like growth factor 1 and interleukin 10 in sportsmen.

Background: Saliva analysis is rapidly developing as a tool for the assessment of biomarkers of sports training. It remains poorly understood whether a short bout of sport training can alter some salivary immune biomarkers. Aim: To investigate the effect of acute exercise using football training session on salivary flow rate, salivary free Insulin-like Growth Factor-1 (IGF-1) and Interleukin 10 (IL-10). Methods: Saliva samples were collected before and immediately after a football session. Salivary flow rates, salivary levels of free IGF-1 and IL-10 (using ELISA) were determined. Data was analyzed and compared using Related Samples Wilcoxon Signed Rank test (non-parametric test). Relationships between salivary flow rate and levels of free IGF-1 and IL-10 were determined using Spearman correlation test. Results: There were 22 male footballers with a mean age of 20.46 years. Salivary flow rate reduced significantly (p = 0.01) after the training session while salivary levels of free IGF-1 and IL-10 did not show any significant change. Also, there were no correlations between salivary flow rates and salivary levels of free IGF-1 and IL-10 before and after exercise. Conclusion: These findings suggest that acute exercise caused significant reduction in salivary flow rate but no change in the levels of salivary free IGF-1 and IL-10.

Active Foreground Region Extraction and Tracking for Sports Video Annotation

Automatic video segmentation plays a vital role in sports videos annotation. This paper presents a fully automatic and computationally efficient algorithm for analysis of sports videos. Various methods of automatic shot boundary detection have been proposed to perform automatic video segmentation. These investigations mainly concentrate on detecting fades and dissolves for fast processing of the entire video scene without providing any additional feedback on object relativity within the shots. The goal of the proposed method is to identify regions that perform certain activities in a scene. The model uses some low-level feature video processing algorithms to extract the shot boundaries from a video scene and to identify dominant colours within these boundaries. An object classification method is used for clustering the seed distributions of the dominant colours to homogeneous regions. Using a simple tracking method a classification of these regions to active or static is performed. The efficiency of the proposed framework is demonstrated over a standard video benchmark with numerous types of sport events and the experimental results show that our algorithm can be used with high accuracy for automatic annotation of active regions for sport videos.

Cooperação e liderança: Uma possível relação

Dissertação de Mestrado apresentada ao Instituto Superior de Psicologia Aplicada para obtenção de grau de Mestre na especialidade de Psicologia Social e das Organizações.

Adaptation of motor control to training and disuse : contribution of muscle synergy analysis and movement variability

The well-known degrees of freedom problem originally introduced by Nikolai Bernstein (1967) results from the high abundance of degrees of freedom in the musculoskeletal system. Such abundance in motor control have two sides: i) because it is unlikely that the Central Nervous System controls each degree of freedom independently, the complexity of the control needs to be reduced, and ii) because there are many options to perform a movement, a repetition of a given movement is never the same. It leads to two main topics in motor control and biomechanics: motor coordination and motor variability. The present thesis aimed to understand how motor systems behave and adapt under specific conditions. This thesis comprises three studies that focused on three topics of major interest in the field of sports sciences and medicine: expertise, injury risk and fatigue. The first study (expertise) has focused on the muscle coordination topic to further investigate the effect of expertise on the muscle synergistic organization, which ultimately may represent the underlying neural strategies. Studies 2 (excessive medial knee displacement) and 3 (fatigue) both aimed to better understand its impact on the dynamic local stability. The main findings of the present thesis suggest: 1) there is a great robustness in muscle synergistic organization between swimmers at different levels of expertise (study 1, chapter II), which ultimately indicate that differences in muscle coordination is mainly explained by peripheral adaptations; 2) injury risk factors such as excessive medial knee displacement (study 2, chapter III) and fatigue (study 3, chapter IV) alter the dynamic local stability of the neuromuscular system towards a more unstable state. This change in dynamic local stability represents a loss of adaptability in the neuromuscular system reducing the flexibility to adapt to a perturbation.

Towards modern municipal sports and recreation management in Costa Rica

Sports and recreation management is addressed here using a model that combines the policies and methodologies applied in the Costa Rican context as a result of a concern to identify the real needs in the sports, recreation, and health promotion fields through the different manifestations of human movement.  This approach has been developed during eight years of work in the Costa Rican Sports and Recreation Institute (Instituto Costarricense del Deporte y la Recreación-ICODER) together with different Costa Rican communities, both rural and urban, and local organizations, such as Comprehensive Development Community Associations, Sports and Recreation Community Boards (CCDR), Municipal Mayorships, and NGOs, among others.  This article particularly takes into consideration the experience of the CCDRs as entities that have been given the responsibility by the Costa Rican Government to promote and manage municipal sports and recreation services with a convenient offering that would meet the needs of users or customers.  In this way, this article is aimed at answering the question on how Boards should conduct an efficient management in a way that they also meet the needs of public users or customers in the municipalities of the country, by proposing a management model that serves as an additional instrument to improving the already existing services managed by the aforementioned entities.  This study presents a model of Costa Rican management structured with the theoretical elements that currently define the organization and planning of sports and recreation as a service.