Effect of Physical Fitness on Response to Orthostasis in Healthy Young Women
Abstract
The purpose of this study was to examine the relationship between fitness level and cardiovascular response to orthostatic stress in healthy women between the ages of 20 and 35. Subjects were divided into three groups on the basis of VOxmax: High-Fit (n = 4; mean VO2max = 57.8 ml/kg/min); Med-Fit (n =8; mean VO2max = 46.4 ml/kg/min); and Low-Fit (n = 4; mean VO2max = 34.7 ml/kg/min) . Subjects were exposed to three trials of 70 deg. head up tilt each followed by a ten minute supine rest period. Heart rate and blood pressure were recorded at 1, 3 and 5 minute intervals during head up tilt and at 5 and 10 minute intervals during the supine rest period. The mean heart rate and blood pressure changes from supine to one minute upright were calculated for each group. The change in heart rate per change in systolic blood pressure from supine to 70 deg. upright was used as an index of baroreflex responsiveness. There was a strong inverse correlation between fitness level and heart rate both resting and at 1 minute upright (r=.83;r=.84 p < .001). An analysis of baroreflex indicies between groups showed no fitness related differences in heart rate and blood pressure response to orthostasis.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 01, 1988
- Accession Number
- ADA196377
Entities
People
- Carolyn K. Gooch
Organizations
- Air Force Institute of Technology