No description available.

No description available.

Thesis (Ph. D.)--University of Hawaii at Manoa, 1991. / Includes bibliographical references (leaves 142-163) / Microfiche. / xi, 163 leaves, bound ill. 29 cm

There is a long history of visual preferences for natural environments over urban environments, as well as beliefs in the restorative value of time spent in natural environments. Diverse theoretical perspectives, such as information overload, learning and evolutionary theories, can be used to help explain these preferences and beliefs, and early empirical research has found tentative support for them. The present study capitalizes on a recovery-from-stress experimental paradigm developed by Ulrich. Subjects are presented with a brief videotaped stressor followed by a brief videotaped outdoor environment while psychological and physiological indicators of arousal and emotion are monitored. In this study, two stressors and four environments were manipulated between subjects. The environments differed along two dimensions that were derived from visual preference research and theoretical predictions: whether they were natural or urban in character, and the presence or absence of a river. Physiological indicators of arousal included heart rate, skin conductance, respiration rate and salivary cortisol levels. Facial electromyographic (EMG) placements were used to assess the emotional valence of subjects' responding. The Zuckerman Inventory of Personal Responses (ZIPERS) was used to assess psychological responding. Analyses yielded a limited and occasionally inconsistent pattern of results. Many of the inconsistent responses to the environments were found across stressors, suggesting that either arousal level or the particular nature of the arousal generated by the two stressors may have interacted with the recovery environments. Despite these inconsistencies, the tentative conclusions that could be reached were generally consistent with past research and theoretical predictions. Evidence from the arousal variables suggested that the Nature and Water environments elicited less arousal during the recovery phase than did the Urban and Non-Water environments; and, there was corraboration or partial corraboration for each of these findings from the self-report data. Similarly, data from the EMG placements favored the Nature environments over the Urban environments, and in particular suggested that the Non-Water Natural (meadow) environment was less likely to produce negative emotions than the other environments. Again, this finding received some support from the self-report data. Possible explanations for the limited and occasionally inconsistent nature of the findings are offered in the discussion section, with the most likely candidate being the relatively attractive Urban environments used in this study compared to those used in past research.

Call number: LD2668 .T4 1985 D37 / Master of Science

This study was designed to assess the appropriateness of current standardized checklists used to measure stressful life events in a noninstitutionalized population aged 65-74 years of age. Previous studies, sampling from a younger aged population, have demonstrated a temporal association between an increase in stressful life events and psychophysiological disease. Before stress can be studied as a precipitator of disease onset in the aged, it must be determined if the instruments designed to measure stress are reliable and valid for use with the aged. Specifically, the following questions were examined: (1) Reliability--Are the checklists reliable for use with this population? (2) Relevance--Are the checklists valid for use with this population? (3) Are these events considered to be stressful for this population? (4) Does the scoring system used influence the results? (5) Are the events included on the checklists events that occur in the lives of people aged 65-74? (6) Are there other events, not on the checklists, which are stressful for older people? The data base for this study consisted of responses from 185 subjects aged 65-74 years. Each respondent completed three standardized checklists designed to measure stressful life events and a demographic sheet which included provision for respondents to write any stressful event(s) that had occurred. Results were analyzed by subscale. As a result of this study it was determined that: (1) Reliability coefficients across subscales were not sufficiently large to warrant using these checklists with this aged population. (2) The three checklists were not valid for use with this aged population. (3) Respondents in this study perceived most events as being more stressful than did a younger age standardized group. (4) Standardized weights for the events should be assigned by people aged 65-74 years. (5) Stressful life events are different for people aged 65-74 years than for younger aged people. It was recommended that the checklists be revised for use with this age population. This revision includes modifying events on the checklist and having people aged 65-74 years assign standardized weights that reflect the stressfulness of the events.

Two investigations were conducted with collegiate golfers for separate, but related purposes. 1) To investigate the effects of a physical conditioning program (strength, power and flexibility training) on clubhead speed, consistency, and putting distance control. 2) To investigate the effects of 36 continuous holes of competitive golf on testosterone and cortisol response and their relation to performance.Study #1: Subjects were ten men and six women NCAA Division I golfers. Supervised strength, power, and flexibility training was performed 3 times per week for 11 weeks. Golf ball launch conditions, putting distance control, strength, power, and flexibility tests were conducted before and after training. Significant (p < 0.05) increases were noted for all strength, power, and flexibility tests. Clubhead speed increased significantly (1.6%) from pre to post training, equating to a 4.9-meter increase in driving distance. No significant differences were observed for clubface-angle or launch-angle deviation. Putting distance performance significantly improved for the men-only group (29.6%). Significant (p < .05) correlations resulted between clubhead speed and rotational power (r = 0.86) for the men-only group. Qualitative video analysis did not show any consistent trends in swing mechanics alterations. Eleven weeks of physical conditioning increased clubhead speed without a negative effect on consistency or putting distance control in intercollegiate men and women golfers. Study #2: Subjects were eight NCAA Division I men golfers. Saliva samples were taken 45 minutes prior to the round and after each hole during a 36-hole competition. Time matched baseline samples were collected. Six and 36-hole area under the curve (AUC) values were calculated for endocrine measures. Salivary cortisol increased by 111% (p < 0.05) during competition compared to baseline. Testosterone-to-cortisol ratio was significantly lower (45%) throughout the competition compared to baseline. Significant (p < 0.05) correlations resulted between: 36-hole AUC testosterone-to-cortisol ratio difference and 36-hole score (r = 0.82), CSAI-2 somatic anxiety and pre-round cortisol (r = 0. 81), testosterone (r = -0.80), and testosterone-to-cortisol ratio (r = -0.72). These results indicate a significant hormonal strain during 10 hours of competitive golf, low TIC ratio relation with low golf scores, and CSAI-2 relation with endocrine measures. / School of Physical Education

Cardiovascular responses and tolerance to an orthostatic stress were examined in eight men before and after eight months of endurance exercise training. Following training, maximal oxygen consumption and blood volume were increased, and resting heart rate reduced. Orthostatic tolerance was reduced following training in all eight subjects. It was concluded that prolonged endurance training decreased orthostatic tolerance and this decrease in tolerance appeared associated with attenuated baroreflex sensitivity and alterations in autonomic balance secondary to an increased parasympathetic tone noted with training.

Life events inventories have been extensively used to investigate the relationship between stressful life events and the etiology of disease. In order to elucidate conceptual and methodological issues surrounding the use of these instruments, a Life Events Questionnaire was constructed and administered to 100 university students. Subjects indicated which of 40 events they had experienced and rated all events on a 20 point scale based on the amount of readjustment judged to be required by each event, both for themselves and for a hypothetical average person. Results of a three-way ANOVA indicated that in the majority of cases, neither the gender nor the experience of the rater, nor the point of reference used in making the judgment had a significant effect on the magnitude of the ratings obtained. For ratings of events which did show significant group differences, the primary finding was that normative values appear to be more consistently applied to estimates of others' reactions than to those of the raters themselves.

A dissertation submitted in fulfilment of the requirements for the degree Master of Science in Engineering, in the Faculty of Engineering and the Built Environment, University of the Witwatersrand, Johannesburg. January 2017 Johannesburg / It is well known that emotional stress has a negative impact on people’s health and physical, emotional and mental performance. Previous research has investigated the effects of stress on various aspects of physiology such as respiration, heart rate, heart rate variability (HRV), skin conductance, skin temperature and electrical activity in the brain. Essentially, HRV, Electroencephalography (EEG), skin conductance and skin temperature appear to reflect a stress response or state of arousal. Whilst the relationship between respiration rate, respiration rhythm and HRV is well documented, less is known about the relationship between respiration rate, EEG, skin conductance and skin temperature, whilst HRV is maximum (when there is resonance between HRV and respiration i.e. in phase with one another). This research project aims to investigate the impact that one session of slow paced breathing has on EEG, heart rate variability (HRV), skin conductance and skin temperature. Twenty male participants were randomly assigned to either a control or intervention group. Physiological data were recorded for the intervention and control group during one breathing session, over a short initial baseline (B1), a main session of 12 minutes, and a final baseline (B2). The only difference between the control and intervention groups was that during the main session, the intervention group practiced slow paced breathing (at 6 breaths per minute), while the control group breathed spontaneously. Wavelet transformation was used to analyse EEG data while Fourier transformation was used to analyse HRV. The study shows that slow-paced breathing significantly increases the low frequency and total power of the HRV but does not change the high frequency power of HRV. Furthermore, skin temperature significantly increased for the control group from B1 to Main, and was significantly higher for the control group when compared to the intervention group during the main session. There were no significant skin temperature changes between sessions for the intervention group. Skin conductance increased significantly from Main to B2 for the control group. No significant changes were found between sessions for the intervention group and between groups. EEG theta power at Cz decreased significantly from Main to B2 for the control group only, while theta power decreased at F4 from Main to B2 for both groups. Lastly, beta power at Cz decreased from B1 to B2 for the control group only. This significant effect that slow-paced breathing has on HRV suggests the hypothesis that with frequent practice, basal HRV would increase, and with it, potential benefits such as a reduction in anxiety and improved performance in specific tasks. Slow-paced breathing biofeedback thus shows promise as a simple, cheap, measurable and effective method to reduce the impact of stress on some physiological signals, suggesting a direction for future research. / MT2017