Although frogs are recognized as accomplished swimmers, no detailed biomechanical study has been done. The hydrodynamics and mechanics of swimming, in the frog, Hymenochirus boettgeri, are investigated in this thesis. Hydrodynamic drag, of the body and splayed hind limbs of preserved H. boettgeri, was assessed by drop-tank experiments. Drag tests were also performed with the semi-terrestrial Rana pipiens. A comparison of their drag coefficients (CD) under dynamically similar conditions, suggests that jumping performance may not compromise the swimming ability of R. pipiens. Drag of the expanded foot of H. boettgeri, and acetate models thereof, was investigated by free fall drop-tank experiments, and a subtraction technique. The results of these methods and flow visualization experiments support the assumption that animal paddles can be treated as three dimensional flat plates, oriented normal to the direction of flow. Cine films were used to study swimming during the near-vertical breathing excursions of H. boettgeri. The acceleration of frogs throughout hind limb extension (power stroke), is distinct from other drag-based paddlers (eg. angelfish and water boatman), which accelerate and decelerate within the power stroke phase. The propulsive force generated during the power stroke of a single sequence (sequence 1) is calculated from quasi-steady drag (static-body drag measurements, see Chapter I) and inertial considerations. Additional components of the forcebalance, including the net effect of gravity and buoyancy, and the longitudinal added mass forces associated with the frog's body, are integrated to establish upper and lower bounds of the propulsive force. The propulsive force remains positive throughout extension. The validity of using static drag estimates to describe dynamic resistance is explored. Results from Chapter II suggest that simple drag-based models may not be sufficient to explain the swimming patterns observed. The right hind limb of the sequence 1 animal was modelled as a series of linked circular cylinders (the femur, tibiofibula, and metatarsal-phalangeal segments) and a flat plate (the foot). A blade-element approach was used to calculate the instantaneous drag-based and accelerative force components (parallel to the direction of motion) generated by hind limb flexion and extension. The negative thrust, generated by hind limb flexion, is probably responsible for the observed deceleration of the sequence 1 animal. Positive thrust is generated only during the initial stages of extension, almost exclusively by the feet. The impulse of the accelerative-based thrust far exceedes the impulse of the drag-based thrust. Negative thrust is initiated midway, and continues thoughout extension, despite the acceleration of the animal. Hind limb interaction, is thought to provide propulsive thrust for the latter half of the extension phase. A jet and/or ground effect may be involved. It is suggested that a combination of reactive, resistive and interactive forces are required to explain propulsion in H. boettgeri, and probably other anurans. / Science, Faculty of / Zoology, Department of / Graduate

Athletics competition represents the classical test of physical fitness or performance capacity. The individual’s performance is the combined result of the coordinated exertion and integration of a variety of functions. Intercollegiate swimmers are an example of highly trained individuals. Their swim training provides almost maximal activation of the aerobic process or the cardiovascular system. This high level of cardiovascular fitness and physical performance is the result of natural endowment plus the specific effects of swim training. INdividuals that began to train vigorously at an early age (as young as 8 years old) have shown increases in several aspects of aerobic capacity. Compared to others of the same age, swimmers have increased cardiac output, stroke volume, vital capacity and total hemoglobin counts. The intensity of the training program has been shown to correlate positively with increases in cardiovascular fitness.

The following purposes were established for the study: 1. To determine the scope of the area known as aquatic art. 2. To determine the basic knowledge and understandings necessary for competent teaching in the area of aquatic art. 3. To present in the form of a handbook principles and procedures for organizing, administering, and conducting an aquatic art program.

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