Maximal exercise during hypobaric hypoxia (447 Torr) in moderate-altitude natives.

Six low-altitude natives (LAN) (373 m or less, aged 19-25 yr) and eight moderate-altitude natives (MAN) (1830-2200 m, aged 19-23 yr) were studied at both their residence (home) altitude (740 Torr and 587 Torr, respectively) and in a hypobaric chamber at a simulated altitude of 4270 m (447 Torr). Following a 2-d adaptation period, subjects performed an incremented test on the cycle ergometer until voluntary exhaustion. Significantly (P less than 0.05) greater differences in percent change of maximum exercise variables (total exercise time, exercise intensity, VO2, VCO2, VE/VO2 and HR) were noted in the LAN group than in the MAN group, going from their residence altitude to 447 Torr. The decrement in VO2max was 15% in the MAN group compared to 34% in the LAN group. The anaerobic threshold (% VO2max), estimated from VE BTPS measurements, was similar in both groups at residence altitude and at 447 Torr. In the morning prior to exercise testing at 447 Torr, LAN subjects reported greater (P less than 0.001) symptoms of acute mountain sickness (AMS) than MAN subjects. Our results indicate that, with respect to maximum exercise performance, moderate-altitude natives are at an advantage during early adaptation to hypobaric hypoxia.

The nomological validity of the Type A personality among employed adults.

The nomological validity of the Type A behavior pattern was explored. The Structured Interview (SI) and a battery of personality trait, physical health, and strain measures were administered to an occupationally diverse sample of 568 workers. Ss were also monitored for physiological reactivity and recovery (blood pressure, heart rate, skin temperature, and electrodermal response) to the SI and a subsequent Stroop Color-Word Conflict Task. A confirmatory factor analysis demonstrated that SI scores can be factored into three distinct dimensions. There was considerable overlap in the patterns of personality traits that characterized the Type A components, but only a Hostility dimension was significantly related to physiological reactivity and recovery. The results have implications for distinguishing coronary-proneness from the more traditional Type A conceptualization.

An interdisciplinary approach to the treatment of a hyperfunctional voice disorder.

The purpose of this article is to describe the treatment of a 45-year-old male with a hyperfunctional voice disorder by a biofeedback therapist and a speech-language pathologist. The interdisciplinary approach to the treatment of this voice disorder involved the combined use of traditional voice therapy techniques and EMG biofeedback procedures together with cognitive behavioral therapy. Voice therapy was facilitated through the use of a computer-based, speech-monitoring system. The remediation of this voice disorder was attributed to the collaborative efforts of two professionals representing diverse professional training and treatment protocols. The results showed reductions in muscle activity in the infrahyoid and laryngeal areas as well as improved use of proper breathing and voicing onset behaviors. Follow-up at 10 and 15 months posttreatment intervals indicated that the client had retained all target voice skills and the tension reduction/biofeedback skills. Results suggest that interdisciplinary, collaborative efforts using biofeedback and voice therapy can prove beneficial in the treatment of hyperfunctional voice disorders.

Cardiovascular responses to emotional stress (quiz interview) in post-myocardial infarction patients and matched control subjects.

In this investigation, 30 male post-myocardial infarction patients and 30 male control subjects matched according to age and occupation were given a 12-minute tape-recorded stress quiz described by Schiffer et al. Cardiovascular responses (electrocardiogram, heart rate, systolic, blood pressure, and diastolic blood pressure) to emotional stimuli were monitored in a laboratory setting at rest before the quiz and at two-minute intervals during the quiz. Heart rate and blood pressure values were significantly higher during the quiz than at rest for both patient and control groups. There was a significantly higher response for diastolic pressure and a significantly lower response for heart rate in the patient group compared with the control group. In the analysis for occupational status in the entire population, systolic pressure was significantly higher for the executives than for non-executives. Subgroup analyses of patients with angina, hypertension and/or ECG changes (N = 12) revealed a significantly higher diastolic pressure response than found in either the patients without these symptoms (N = 18) or in the controls (N = 30). In comparison to exercise test results, the emotional stress test (quiz) elicited somewhat more PVC's but less ST segment depression. These results support previous reports suggesting that emotional stress testing may be a valid tool in the diagnosis of coronary heart disease and in determining the physiological mechanisms which underlie the association between emotional stress and coronary heart disease.

Convergent validity of type A behavior pattern scales and their ability to predict physiological responsiveness in a sample of female public employees.

The purpose of this study was to assess the construct validity of the structured interview (SI), Jenkins Activity Survey (JAS), Thurstone Activity Scale, and Bortner Type A Scale in a sample of female employees from a government service agency. Criteria for validity assessment were physiological reactance to a mental stressor, psychological strains experienced at work, physical symptoms associated with work, and urinary catecholamine production at work. A continuous Type A SI scale demonstrated better convergent and construct validity than did the SI category scores. All of the SI Type A scales were reliable. Among the questionnaire measures only the Thurstone Activity Scale was reliable and showed the strongest construct validity. The SI measures of Type A tended to correlate with physiological responsiveness (changes in heart rate, skin temperature, and skin conductance), while the questionnaire measures correlated with self-reports of job strains (satisfaction, irritation, depression, physical symptoms), thus indicating the operation of measurement artifacts in validity assessment. No significant correlations were obtained between Type A and catecholamines. Comparison of correlation analysis with subgroup analysis revealed the former to be a more powerful test of the relationships that may exist between Type A behavior pattern and relevant criteria.

Incidence of stress-related disorders among American and Brazilian men and women.

Cross-cultural differences in physical and emotional responses to stressors are reported in this study. Among professionals (e.g., managers, supervisors), the incidence of stress-related disorders can have remarkable impact upon organizational performance as well as personal well-being. In order to study the relationship of nationality and gender to stress-related disorders, 148 American and 180 Brazilian professionals completed a questionnaire asking them to identify their unique responses to occupational stressors. Statistical analysis indicated that significant differences exist between the responses based upon both nationality and gender. Specifically, Americans reported a significantly higher incidence of allergies and irritable bowel syndrome, while Brazilians reported a higher incidence of Raynaud's syndrome (major manifestations are cold hands/feet). The males reported a higher incidence of high blood pressure and TMJ dysfunction/bruxism (a major manifestation is teeth grinding), while the females reported a higher incidence of tension headaches. The results are discussed in comparison to other cross-cultural and cross-gender studies with similar outcomes.