In this thesis we describe two instances of the nonlinear interaction between a fluid and an elastic solid to mimic or explain some phenomenon seen in nature. We focus on the phenomena of singing of small song birds and swimming of small fish. Song birds show a versatile range of tones and compositions that have highly complex spectral structure, while fish cut through water with amazing ease. The complexity of the Navier Stokes Equations that describe the fluid coupled with large deformation elasticity equations, makes analytic attempts intractable. Hence experiments were carried out with simple physical models to explain these observations. In the first case a cylindrical elastic tube (2.5cm long, 2.5mm diameter) was used to model the vocal organ, the syrinx, of a song bird. Muscle action was mimicked using a linear motor that implemented a squeezing action and the action of the lungs was modeled by a constant source of air flow. The combined fluid-elastic system behaved like a nonlinear dynamical system and produced sound under certain conditions of external parameters. Moreover the structure of the sound created depended sensitively on the control parameters, which in this case was dominated by the position of the linear motor. The motor was dynamically controlled to produce a range of songs from simple tonal ones of the Vireo to the complex chaotic songs of the Zebra Finch. In the second instance, a cantilever (5cm long, 1cm wide)suspended between and driven by magnetic coils arranged in an anti-Helmholtz configuration, was used to mimic the dynamics of the caudal fin of a small fish. Three different gaits were observed as a function of the control parameter, the drive frequency. One of these gaits maximized thrust and hydrodynamic efficiency, and velocities unto 6 body lengths per second were measured. / Engineering and Applied Sciences

Hagfishes have both intrigued and confused biologists since Linnaeus first mistakenly classified one as an "intestinal worm." Modern hagfishes (Myxinidae) are elongate, marine fishes often described by what they lack: jaws, scales, paired fins, or a vertebral column. Accompanying this reduced morphology was a long-held view that hagfish are lazy animals that mostly lay about on the ocean floor, but more recent research has revealed them to be active hunters and scavengers in the benthic community. Routine swimming is a requisite part of these activities, yet knowledge of how these exceptionally flexible fishes swim is limited. Here, I use an integrative experimental approach to provide a more comprehensive, quantitative understanding of locomotory mechanisms in hagfishes. In Chapters 1 and 2, I use high-speed videography to quantify whole-body kinematics of steady and unsteady swimming in Eptatretus stoutii and Myxine glutinosa, representing the two main lineages within Myxinidae. Both species generally swim with high amplitude head movements and use tail beat frequency to control swim speed, but inter- and intra-specific variation in other undulatory wave variables suggests multiple mechanisms to modulate speed. Changes in the shape of the body wave characterize the observed unsteady swimming behaviors. During positive linear accelerations, hagfish transiently adopt a larger, longer body wave. During lateral maneuvers, hagfish approximate “sidewinding” behavior as anterior body regions interact with the substrate while posterior body regions propagate waves of lateral bending toward the tail tip. Chapter 3 integrates kinematics with hydrodynamics, using particle image velocimetry to visualize the flow field around swimming E. stoutii. The steady swimming wake consists of caudolateral fluid jets, which turn caudally during linear accelerations. Wake jets orient asymmetrically during lateral swimming, contributing both forward and lateral thrust over a complete tail beat. The hydrodynamic patterns observed reinforce kinematics-based hypotheses on how hagfishes enact their various swimming behaviors. In Chapter 4, I use simple robotically-controlled physical models to examine functional relationships between body flexural stiffness, shape, kinematics, hydrodynamics, and swimming performance. I relate model swim performance to characteristics of hagfish swimming, and describe lessons that passively undulating models impart for understanding locomotion by live elongate undulatory swimmers.

Enteric pathogens in pool water can be unintentionally ingested during swimming, increasing the risk of Acute Gastrointestinal Illness. Swimmer activities and behaviors influence pool water ingestion rates, and can be quantified for use in risk assessment. Enteric infection risk estimates help identify data gaps, areas to focus resources, and research needs. Primary objectives of this study were to develop electronic, self-administered "exposure" and "pool operations" questionnaires; to gather swimmer behavior and activity data for use in risk assessment; and to estimate Cryptosporidium parvum infection risk in swimmers. Results were used to identify data gaps and future research needs relative to treated recreational water. To achieve these objectives, 126 swimmers were recruited at four pool sites in Tucson, Arizona, video-taped, and asked to complete a post-swim questionnaire. Forty-six of the 126 swimmers submitted a 24 hr post-swim urine sample for quantifying pool water ingestion. Head submersion frequency and duration and splashes to the face were observed and quantified in video analysis, and activities and behaviors were reported on the exposure questionnaire. Variable data were analyzed for associations with pool water ingestion estimated by urinalysis. Results indicate questionnaires can be self-administered electronically; the exposure questionnaire can be used to estimate ingestion magnitude in place of urinalysis; leisure swimming activities (diving, playing, splashing, wading, sitting) and frequency of face splashes are ingestion exposure factors; and that Cryptosporidium infection risk is greatest among leisure swimmers. Other activities observed and suspected of having associations with ingestion were short submersion durations (<1 sec), and spitting and spouting water. More research and resources focused on improving treated recreational water environments and reducing risks among swimmers are needed. Developing an indicator organism test representative of Cryptosporidium, a monitoring program for treated recreational water, education aimed at leisure swimmer, and routine engineering and administrative controls are recommended. Swimming is a unique activity that can be enjoyed by people of all ages and abilities. Controlling hazards in pool environments reduces Recreational Waterborne Illness risks associated with pool water ingestion and improves the health and safety of swimmers.

The purpose of this study was to examine the utilization of imagery and the impact of imagery use on collegiate synchronized swimmers. Swimmers (N=165) completed The Sport Imagery Questionnaire (Hall et al. 2005), reporting their frequency of imaging. Interviews were conducted (N=11) to further ascertain why and when synchronized swimmers use imagery and mechanisms they employ for more effective imaging experiences. Exploratory factor analyses indicated three of Hall et al's (2005) five subscales showed significant differences between skill level groups. Specifically, motivational specific functions of imagery data showed significant differences between elite swimmers and the other three groups (advanced, intermediate, and novice). Cognitive specific and motivational general-mastery functions of imagery data indicated significant differences between elite and novice swimmers, suggesting that novice swimmers are less likely to use these subscales of imagery compared to elite swimmers. Qualitative data provided evidence of elite swimmers having more sophisticated and developed applications of imaging skills. The results suggest the global implications of this study and how imagery improves synchronized swimming training programs. Key findings include: Each progressive skill level had better imaging skills and utilization than the lower levels Years experience, repetition, and training impact synchronized swimmers use of imagery The very nature of certain common synchronized swimming drills such as "think-throughs and land drill" elicit imaging training The sport of synchronized swimming is an excellent instrument to research imaging training techniques.

This thesis considers the perceived athleticism of synchronized swimming by looking at the implications of representations of Esther Williams and "pretty swimming" in popular culture, the allocation of space for women's sport in a local public swimming pool, and an inaugural championship event. Focusing on the first British Columbia (BC) synchronized swimming championships, which were held on February 5, 1949 at Crystal Pool in Vancouver, it shows that images of synchronized swimming as "entertainment" facilitated the development of a new arena of competition for BC women, but that this was accompanied, in effect, by a trivialization of the accomplishments of organizers and athletes. Chapter One examines the construction of a "global" mermaid by analysing Esther Williams' first film, Bathing Beauty (1944), as a typical example of the Metro-Goldwyn- Mayer (MGM) aquamusical, a genre that produced images of synchronized swimming as frivolous entertainment. Chapter Two considers how these sorts of images affected the allocation of physical space at Crystal Pool, Vancouver's only indoor public swimming pool at the time, for women's sport. Chapter Three introduces two women who were involved in the 1949 BC synchronized swimming championships: May Brown, who at the time was a University of British Columbia (UBC) Physical Education instructor and synchronized swimming judge, and Maureen Bray (Hibberson), a UBC student who won the individual championship event. Their recollections provide an important corrective to the "pretty swimming" stereotype by demonstrating that these women used the cultural and physical space allotted to them to create a new sport for local women. The final chapter also includes episodes from my personal experiences as a synchronized swimmer in BC during the 1980s to underscore the complicated and conflicted heritage for synchronized swimmers in BC represented by the legacy of the 1949 championships and the MGM aquamusical.

The purpose of this study was to determine the influence of swimming on 10-12 years old children. There were 4 groups of schoolchildren: swimming group of boys (25 persons), swimming group of girls (15 persons), boys nonswimming group (25 persons) and girls nonswimming group (15 persons). There were 80 schoolchildren with the average age of 11,2±0,74 years. The high and weight were measured. Also were measured size of a chest, vital capasity. The results showed that no solid diference of high were found between the groups. Higher values of body mass were found in both swimming groups in comparison with nonswimming groups. Larger vital capasity were also found in swimming groups. The results showed that swimmers had stronger pulmonary system than nonswimmers. There was found positive efect of swimming on pulmonary system, swimming also helps to increase vital capasity of 10-12 years old pupils.

Having the same parents repeatedly complete questionnaires over time, the current community based study investigated beliefs relevant to supervision, drowning risk, and water safety for children aged two through five enrolled in swim lessons. Results revealed that many parents value swimming lessons for young children and view supervision as an important prevention approach. Water safety beliefs and accuracy in judging children’s swim abilities improved over lessons, but time in lessons was related to endorsing poorer supervision of children near water. Having experienced a “close call” for drowning was found to make parents more aware of drowning risk and the importance of close supervision. Results highlight the need for parent education that targets beliefs about water safety and supervision during lessons, and also suggest that a close call for drowning may act as a “teachable moment” for parents and be an appropriate time to implement such interventions.

Twelve middle aged men and women (23-59 years) participated in twelve weeks (36 sessions) of endurance swim training at an approximate intensity of 75% maximum heart rate (Karvonen Method) (14). This training resulted in improved cardiorespiratory fitness as evidenced by a significant (9.4%) increase in mean maximal oxygen uptake (liters/ min.) and a significant bradycardial response during submaximal walking. Subjects lost significant amounts of subcutaneous body fat, as measured by skinfold calipers, but experienced very little change in absolute body weight (.1 kg.) suggesting an increase in muscle weight. Data from the submaximal walking test, administered after each 12 session period of training, showed a nonlinear decline in heart rate throughout training. This, possibly, was in response to an accumulating fatigue factor brought on by a rapid increase in the amount of total work that the subjects were doing during the middle stage of training.

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This study examines the effects of acceleration on fluid forces acting on the hand in swimming and presents a new pressure method to predict fluid forces acting on the accelerating hand. Swimmers and coaches require accurate information about swimmers� fluid forces, propulsion and drag, in order to improve performance. In general, swimmers are likely to generate propulsion mainly with their hands in the front crawl stroke, butterfly and back crawl stroke. Researchers have attempted to estimate the fluid forces on the hands with various techniques including a cinematographic method (a "quasi-static" approach), a pressure method and a numerical method of computational fluid dynamics. However, the effect of accelerations on fluid forces acting on the hand has not yet been well quantified. Understanding of the effect of acceleration on fluid forces on the hand can provide useful information to enhance swimming performance. Also the developments of a method to predict fluid forces acting on the accelerating hand in swimming can be used to evaluate swimming performance more accurately. The present study used a hand model attached to a load cell to measure forces in three orthogonal directions and pressure sensors to measure pressures on the hand model rotated in the flume. The model position was measured by a potentiometer fixed to the axis of the model rotation. The quantification of the effect of acceleration was based on a simple theoretical understanding for fluid mechanics, using the inertia coefficients and the coefficients of fluid forces, that is widely accepted in other disciplines. The quantification was focused mainly in the direction tangential to the model rotation because the magnitude of the velocity changed in this direction. The overall effect of acceleration on fluid forces on the hand model was that the inertia coefficients increased rapidly in the early phase of the model movement, then in the final deceleration phase of model movement the inertia coefficients decreased to a negative value and then became small. The inertia coefficient increased in the impulsive start of the hand model, indicating that fluid forces acting on the hand increased as accelerations of the hand increased. This result was consistent with the simple theoretical understanding to induce additional fluid forces on the hand, that is, fluid forces on the hand increased as accelerations increased. However, the inertia coefficient decreased and reached large negative values in the late phase of the model movement involving decelerated motion, indicating that fluid forces on the hand increased as acceleration of the hand decreased to negative values (decelerations). That result was not consistent with the simple theoretical understanding to induce additional fluid forces on the hand because the simple theoretical understanding cannot take account of the preceding history of the fluid motion around the hand model associated with the formation of vortices. Thus, more sophisticated theory is needed. The dynamic pressure measured by the pressure sensors implied that the induced fluid forces might be due to large attached vortices behind the hand model. The hand was considered as a blunt body when the angle of attack was large (maximum = 90�) and an aerofoil shape when the angle of attack was small. The inertia coefficients became large when the hand model was set at the large angles of attack, indicating that the effect of accelerations on the hand model increased when the hand surface was directed to the on-coming flows (blunt body). For the development of the new pressure method, a regression analysis was used to build a single best-fit equation to predict fluid forces acting on the accelerating hand model. The single best-fit equation was acquired for various orientations of the hand model. The accuracy of prediction of fluid forces acting on the accelerating hand model was checked by a root mean square (RMS) difference. The RMS difference by the pressure method was approximately half of the RMS difference by the "quasi-static" approach that has been a major method to predict fluid forces exerted by the hand in swimming. The present study has quantified the effect of acceleration on fluid forces acting on the hand in swimming and developed a new pressure method including acceleration effects to predict fluid forces acting on the accelerating hand.