Changes in aerobic power of women, ages 20-64 yr.

This study quantified and compared the cross-sectional and longitudinal influence of age, self-report physical activity (SR-PA), and body composition (%fat) on the decline of maximal aerobic power (VO2peak) of women. The cross-sectional sample consisted of 409 healthy women, ages 20-64 yr. The 43 women of the longitudinal sample were from the same population and examined twice, the mean time between tests was 3.7 (+/-2.2) yr. Peak oxygen uptake was determined by indirect calorimetry during a maximal treadmill test. The zero-order correlation of -0.742 between VO2peak and %fat was significantly (P < 0.05) higher then the SR-PA (r = 0.626) and age correlations (r = -0.633). Linear regression defined the cross-sectional age-related decline in VO2peak at 0.537 ml.kg-1.min-1.yr-1. Multiple regression analysis (R = 0.851) showed that adding %fat and SR-PA and their interaction to the regression model reduced the age regression weight of -0.537, to -0.265 ml.kg-1.min-1.yr-1. Statistically controlling for time differences between tests, general linear models analysis showed that longitudinal changes in aerobic power were due to independent changes in %fat and SR-PA, confirming the cross-sectional results. These findings are consistent with men's data from the same lab showing that about 50% of the cross-sectional age-related decline in VO2peak was due to %fat and SR-PA.

Changes in aerobic power of men, ages 25-70 yr.

This study quantified and compared the cross-sectional and longitudinal influence of age, self-report physical activity (SR-PA), and body composition (%fat) on the decline of maximal aerobic power (VO2peak). The cross-sectional sample consisted of 1,499 healthy men ages 25-70 yr. The 156 men of the longitudinal sample were from the same population and examined twice, the mean time between tests was 4.1 (+/- 1.2) yr. Peak oxygen uptake was determined by indirect calorimetry during a maximal treadmill exercise test. The zero-order correlations between VO2peak and %fat (r = -0.62) and SR-PA (r = 0.58) were significantly (P < 0.05) higher that the age correlation (r = -0.45). Linear regression defined the cross-sectional age-related decline in VO2peak at 0.46 ml.kg-1.min-1.yr-1. Multiple regression analysis (R = 0.79) showed that nearly 50% of this cross-sectional decline was due to %fat and SR-PA, adding these lifestyle variables to the multiple regression model reduced the age regression weight to -0.26 ml.kg-1.min-1.yr-1. Statistically controlling for time differences between tests, general linear models analysis showed that longitudinal changes in aerobic power were due to independent changes in %fat and SR-PA, confirming the cross-sectional results.

Evaluation of the NASA/JSC blood pressure screening clinic.

This study evaluated the NASA/Johnson Space Center's blood pressure screening program, which was designed to identify the proportion of NASA employees who were hypertensive and to identify self-report variables related to elevated pressures. In 1978, a random sample of 3892 employees was selected from over 2,100 NASA employees. Twenty-eight percent were classified as hypertensive by the criterion of systolic pressure of 140 or above or diastolic pressure of 90 or greater. Approximately 16% of all employees had a history of hypertension; the remaining 12% of the identified hypertensives were unaware of their potential health problem. Multivariate analysis showed that elevated systolic pressures were more prevalent in the older, heavier employees. Of hypertensives under treatment, about 74% were under poor control as judged from blood pressures randomly taken at their place of employment. These results demonstrated the effectiveness of screening for unsuspecting hypertensives in industry.

Longitudinal evaluation of an exercise prescription intervention program with periodic ergometric testing: a ten-year appraisal.

The purpose of this investigation was to identify the longitudinal physiological and cardiological changes that occurred in a sample of male NASA executives who participated in an individualized physical conditioning program for 10 years. Only 19% discontinued program participation. Oxygen uptake increased significatnly during the 10 years and the increase was attributed to those who exercised three or more days per week. Serum cholesterol exhibited an upward trend similar to the trend reported in the Framingham population, but systolic blood pressure decreased with age. About 30% of the executives exhibited cardiac arrhythmias during exercise. The incidence of PVCs and PACs increased with age. During the period studied, five executives developed sudden acute myocardial symptomatology which was not detected by the exercise stress test.

Intra-His bundle block complicating acute inferior myocardial infarction.

The unexpected findings of atrioventricular block or delay in the His bundle and proximal branches are described in a 51-year-old man with acute inferior myocardial infarction with narrow QRS complexes. With the information from the His bundle electrogram, the site of atrioventricular block is precisely localized.

Extensive coronary artery disease in a young woman.

PIP: A case history is presented of a 26-year-old woman who complained of substernal and left arm pain during such activities as making a bed, dancing, vacuuming and intercourse. She was diagnosed as having hyperlipidemia and mild hypertension. During the time that she took oral contraceptives (OCs) she was free of chest pain and could pursue normal activity. Coronary bypass surgery with saphenous vein graft resulted in the patient's death in the operating room. Autopsy revealed extensive atherosclerotic occlusive disease of the coronary arteries. It is generally thought that the high levels of circulating estrogens in OCs exert a protective action upon the coronary arteries.^ieng