Aortic Baroreceptor Reflex Control of Blood Pressure: Effect of Fitness (open access)

Aortic Baroreceptor Reflex Control of Blood Pressure: Effect of Fitness

Aortic baroreflex (ABR) control of blood pressure was examined in 7 untrained (UT) and 8 endurance exercise trained (EET) young men. ABR control of blood pressure was determined during a steady state phenylephrine infusion to increase mean arterial pressure 10-15 mmHg, combined with positive neck pressure to counteract the increased carotid sinus transmural pressure, and low levels of lower body negative pressure to counteract the increased central venous pressure. Functioning alone, the ABR was functionally adequate to control blood pressure. However, ABR control of HR was significantly diminished in the EET subjects due solely to the decrease in the ABR sensitivity. The persistent strain from an increased stroke volume resulting from endurance exercise training could be the responsible mechanism.
Date: May 1992
Creator: Andresen, Jean M.
System: The UNT Digital Library
The Effectiveness of an Exercise Intervention Program in Reducing Cardiovascular Risk Among Employees in a University Setting (open access)

The Effectiveness of an Exercise Intervention Program in Reducing Cardiovascular Risk Among Employees in a University Setting

Nine physiological measures were evaluated pre- to post-intervention on subjects participating in a university health promotion program over a seven-month period. Frequency of program attendance and choice of activity were also assessed. Of the 88 employees initially screened, most of the subjects were staff members (n=82, 93%),with a majority being female (n=68, 77%). Significant differences in physiological measures were found pre- to post-intervention between "higher" and "lower" cardiovascular risk participants, primarily due to the type of activity chosen. .The results indicate that health promotion programs at a university are an effective way to have an impact on employees in reducing their cardiovascular risk factors.
Date: May 1992
Creator: Ball, Susan J. (Susan Jean)
System: The UNT Digital Library
Predicting Peak Oxygen Uptake from Ratings of Perceived Exertion During Submaximal Cycle Ergometry (open access)

Predicting Peak Oxygen Uptake from Ratings of Perceived Exertion During Submaximal Cycle Ergometry

The purpose of this study was to predict VO2pak using ratings of perceived exertion (RPE), heart rate (HR), and percent fat (PFAT). Subjects were males (n= 60) (PFAT, M SD = 14.4 6.1) and females (n= 67) (PFAT, M SD = 23.4 4.9) with ages ranging from 18 to 33 years. Subjects performed an incremental cycle ergometer protocol and RPE, HR and Vo2 were measured at each stage until VO2 ak was achieved. Mean RPE and HR at the submaximal workload of 100 watts were, (RPE100) M= 12.7 2.6 and (HR100) M= 146.924.7 respectively. Correlations (p< .001) with VO2p. were -.75 (PFAT), -.66 (HR100), -.67 (FIPE100). The multiple correlation using PFAT, HR100, and RPE100 as predictors of VO2pak was .83 (SEE= 5.28 ml-kg BW'smin"). Each predictor contributed to the correlation (p<.01). The results indicate that PFAT combined with exercise responses of RPE and HR provide valid estimates of VO2peak with a relatively small SEE.
Date: May 1992
Creator: Fairfield, Eric S. (Eric Scott)
System: The UNT Digital Library