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.

No description available.

No description available.

Bimodal resprometry was conducted on reedfish, Calamoichthys caabricus, acclimated to 25C and 33C. The relative proportion of aerial respiration to the total oxygen consumption increased with acclimation temperature (p<0.05), directly correlated to activity (p<0.01) and was inversely correlated with dissolved oxygen (p<0.01). Reedfish survived aquatic hypoxia (<1 ppm) for days solely using aerial respiration. Not surprisingly, reedfish exhibited no behavioral avoidance of aquatic hypoxia when given access to air.

No description available.

No description available.

No description available.

No description available.

No description available.

Patients with autonomic dysfunction have benefited from balancing of parasympathetic and sympathetic activity through the practice of slow breathing exercises. In preliminary studies, patients with various autonomic dysfunctions used biofeedback of respiratory activity to slow breathing to a cadence of six cycles per minute, a frequency known as the resonant frequency (Vaschillo, Vaschillo, & Lehrer, 2006). Breathing at this rate produces cardiovascular resonance (large oscillations in heart rate and blood pressure), forcing the autonomic nervous system to continuously regulate these changes, thereby exercising, and eventually strengthening autonomic control over hemodynamic events. The present study examined several methodologies, such as slow breathing exercises, which are believed to strengthen autonomic control by inducing cardiovascular resonance. Specifically, the current experiment compared different methods of inducing cardiovascular resonance, such as paced breathing and biofeedback assisted protocols. The utility of positive emotion inductions to attenuate respiratory discomfort during slow breathing exercises was also examined. Accurate estimation of the resonant frequency using respiratory methods was largely unsuccessful. However, all respiratory methods produced profound effects in the cardiovascular system, with some differences in the magnitude of effect. In addition, the utility of an emotion induction during slow paced breathing was also demonstrated. The results of this study also support the notion that slow breathing improves pulmonary gas exchange efficiency, in addition to strengthening the baroreflex, by increasing heart rate variability. / Master of Science