No description available.

Ability to duplicate an inspired volume level was studied in five healthy males using the psychophysical method of reproduction. Three conditions were evaluated in order to investigate the perceptual cues used for obtaining a specific inspired volume. Conditions were designed to progressively remove cues that might affect the subject's ability to duplicate an inspired lung volume. In each, the subject performed a standard inspiration, spanning from end expiratory position to 35% of inspiratory capacity. Conditions were varied as follows: (1) subjects were instructed to perform both the standard and test (reproduction) inspirations at the same flow rate and beginning at the same lung volume, (2) subjects were instructed to make the flow rate of the test inspiration faster or slower from standard inspiration, and (3) subjects were instructed to begin the test inspiration at a different lung volume than the standard inspirations. The group mean error for all conditions combined for the first day on which each condition was performed was 173 ml, compared to a mean error of 133 ml. Reduction in errors for all conditions from the first to the second day of performance indicates a practice effect. There was no significant difference in errors between conditions. These results indicate the final lung volume, which remained constant for all three conditions, is important for accurate duplication of inspired volume. This finding for learned respiratory movements is comparable to that found by other researchers for skilled limb movements.

published_or_final_version / abstract / toc / Physical Education and Sport Science / Master / Master of Philosophy

The present study was designed to investigate the hypothesis that individuals with the Hyperventilation Syndrome (HVS) are predominantly thoracic breathers. An analogue population was used to examine the breathing patterns of likely (N = 16) as opposed to unlikely (N = 16) hyperventilators. The relative thoracic as opposed to abdominal contribution to total respiratory volume was assessed during periods of quiet breathing and mild stress. Differences in thoracic contribution to total respiratory volume were not found between the likely and unlikely hyperventilators, nor between the quiet and mild stress conditions. A significant effect for sex existed, with females demonstrating a greater thoracic contribution to total respiratory volume than males. A significant group by sex interaction occurred, with likely male hyperventilators displaying a significantly lower thoracic contribution to total respiratory volume than both likely and unlikely females. Results are discussed in terms of application to the HVS, and future avenues of research are suggested.

No description available.

Call number: LD2668 .T4 1985 M3775 / Master of Science / Electrical and Computer Engineering

No description available.

The ventilatory threshold (VT) is measured frequently during graded exercise tests (GXT) for exercise prescription purposes. The computerized V-slope method for VT determination has been reported to be valid yet little data exists concerning the reliability of the measure. The purpose of this study was to determine the reliability of the VT using the computerized V-slope method. Sixteen healthy volunteers, (eight men and eight women) ages 21-27 (23.6 ± 1.7yrs), performed three maximal GXT on an electronically-braked cycle using an individualized ramp protocol. A minimum of 48 hours separated each test; all three tests were completed within two weeks. Breath-by-breath analysis of gas exchange was performed using a SensorMedics 2900 cart. The VT, expressed as L • min1, was selected by a computerized V-slope method. There were no differences in V02 max between the 3 trials, (overall mean 3.18 ± 0.87 L - min-1). No significant differences were observed for V02 at VT (L - min-1) for tests 1, 2, and 3 (1.62 ± 0.44, 1.58 ± 0.49, and 1.49 ± 0.48) respectively. The VT was determined to be 49.7 ± 7.9% of V02 max. Correlations between the VT in trials 1-2, 1-3, and 2-3 were 0.829, 0.791, and 0.925, respectively. The overall coefficient of variation (C.V.) of the VT measures was 10.61 ± 5.1%. The overall (male and female) variability in VT was 1.28 ± 0.63 METS. Due to high variability and a wide range in correlations, the results failed to support the reliability in the computerized V-slope method. / School of Physical Education

No description available.

Call number: LD2668 .T4 1984 R516 / Master of Science