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This thesis investigated the relationship of ratings of perceived exertion (RPE) with heart rate (HR) and blood lactate (La) that involved four studies. The first study concerned comparing RPE relationships with elite swimmers during exercise tests performed during in-season (IS) and off-season (OS) periods of training. The second study examined the effect of high ambient temperatures on the HRRPE and La-RPE relationship in elite cyclists during self-paced cycle tests. The third study investigated the effect of acute simulated moderate altitude (1800m) exposure on the HR-RPE and La-RPE relationship in highly trained cross-country skiers during incremental ski-striding treadmill tests. The fourth, and final study, was concerned with RPE relationships during upper and lower body work with elite kayakers and elite cyclists.

This study presents the findings of an investigation of the effects of two different treatments, progressive relaxation and cerebral electrotherapy, on heart rate. With progressive relaxation, the subject relaxes by following instructions. With cerebral electrotherapy, relaxation is due to an external source of stimulation. Decreases in heart rate for subjects receiving progressive relaxation were compared with decreases for subjects receiving cerebral electrotherapy. A placebo group was used to evaluate the effects of both treatments independently. While decreases in heart rate were observed for both treatments, only progressive relaxation produced decreases significantly greater than those of the placebo group. However, decreases in heart rate produced by progressive relaxation were not significantly greater than decreases produced by cerebral electrotherapy.

This study concerned the effect of ethanol on cardiac activity and brain respiration in chick embryos. Ethanol dosages tested ranged from 1.0 mg to 4.0 mg/g weight. Each experiment lasted at least 150 minutes. Cardiac activity in terms of total waveform energies was integrated and printed out for plotting and analysis. The embryonic heart rates were simultaneously determined from physical graph tracings. The embryonic brain respiration was measured using a differential microrespirometer. The effect of ethanol on cardiac activity was one of slight (10 to 13), but statistically significant (p

In this study the effects of age (18-55 years), differing levels of fitness (VO 2max ranging from 35.5 to 68.8ml.kg-1.min-1) and endurance training (10 weeks) on heart rate control were investigated. Fitness level was initially determined by a VO2max stress test, succeeded by cold hand and cold face pressor test of autonomic activity. Following these baseline measurements, the subjects (32 nonsmoking male volunteers) were endurance-trained three to four times a week for a 10-week period. The baseline tests were readministered following the 10-week dynamic exercise training period. These data suggest that a natural consequence of aging is a diminishment of autonomic heart rate control; however, endurance training appears to interrupt the aging influence. Individuals of low fitness level appear to have heart rate control dominated by the sympathetic system, while individuals with high fitness levels have a vagally dominated heart rate control system.

The purposes of the study were to compare ratings of perceived exertion of aerobic dance and treadmill performances under equal work loads and to compare ratings of perceived exertion by males and females in aerobic dance and treadmill work. Subjects were twenty-six college men and women in co-educational conditioning classes. Heart rates were monitored after work bouts and perceived exertion was determined using Borg's RPE scale. Data were analyzed by a two-way analysis of variance with repeated measures. Conclusions of the investigation were: (1) aerobic dance is perceived as less strenuous than the treadmill under equal work loads, and (2) males and females perceive aerobic dance as less strenuous than the treadmill under equal energy bouts.

This study examined the effects of music and metronomic beat on heart rate (HR). ratings of perceived exertion (RPE). and physical endurance in healthy females ages 18 to 30. Volunteers were screened via a health questionnaire and the Astrand Work Test on a Monark bicycle ergometer. yielding a predicted aerobic working capacity (V02) of 28 mililiters or more. The 30 subjects were then randomly assigned to one of two experimental conditions (music or metronome group) for a cycling test at 75% capacity. HR and Borg RPE were measured repeatedly, with a posttest measure of physical endurance (kilometers travelled). No significant differences were found between the groups in HR. RPE. or kilometers travelled. A music questionnaire administered to the music group following the posttest examined the subjects' preference for and familiarity with the music, perceived and preferred volume, and experience with music. Trends and suggestions for future research are discussed.

Boucharq and Corson (1976) found that subjects required to lower heart rate to avoid the loss of money used the strategy of attending to meaningless stimulation twice as often as subjects required to lower heart rates to obtain money, and that subjects decreasing heart rate to avoid the loss of money performed significantly better than subjects required to lower heart rate to obtain money. Seven male and seven female undergraduates participated in a study designed to test the hypothesis that visual focusing on meaningless stimulation and biofeedback would produce larger heart rate decreases than biofeedback alone. Each subject attended three baseline sessions followed by six treatment sessions in which subjects experienced either biofeedback and the meaningless stimulus, or biofeedback alone. The principal dependent measure was heart rate, although frontalis EMG, and EEG Alpha/Theta production were recorded for correlation with heart rate. The results showed that the biofeedback and meaningless stimulus group showed significantly higher heart rates on four of the six treatment sessions when compared to the biofeedback alone group, although neither group evidenced a learning curve. Correlations between heart rate and EMG, and heart rate and EEG frequencies were nonsignificant for all sessions. The findings of this study do not support Bouchard and Corson's (1976) hypothesis that subjects who learned to reduce heart rate did so by focusing attention on meaningless stimulation.

Defibrillators are medical equipments which are widely used to resume the normal pacemaking activities of the heart in patients with myocardivim abnormalities. Electrical defibrillation is usually achieved by passing an electrical current pulse transthoracically through the heart of the patient. The source of this electrical current is usually a high voltage capacitor. The successful operation of defibrillators depends on two parameters, Transthoracic Resistance (TTR) and the peak defibrillation current. So far, control of this peak current during defibrillation by measurement and adjustment of the TTR has not been attempted (adaptive defibrillation). In this thesis, a method is described for implementing such an adaptive defibrillator by control of the defibrillator current.

To test this a three part study would be required. First, it should be determined if there is a difference between the threshold for perception of increased heart rate in psychopaths and normals in order to see if the problem is an attentional one. If such a difference were not found the next step would be to compare psychopaths and normals on the strength of the cognitive fear reaction to Sarm the source of which in this case is increased heart rate. Finally, if results show no cognitive fear attached to the awareness of their increased heart rate, an attempt would be made to condition fear to the physiological stimulus of increased heart rate. The following study was concerned with completion of the initial phase of this three part study.