Accession Number : ADA337800

Title :   Effects of Human Pregnancy on Responses to Exercise Above and Below the Ventilatory Anaerobic Threshold.

Descriptive Note : Annual rep. 1 Oct 96-30 Sep 97,

Corporate Author : QUEEN'S UNIV KINGSTON (ONTARIO)

Personal Author(s) : Wolfe, Larry A.

PDF Url : ADA337800

Report Date : OCT 1997

Pagination or Media Count : 71

Abstract : The purpose of this contract is to study the effects of healthy human pregnancy on cardiac autonomic function (Study #1), oxygen uptake kinetics (Study #2), and acid-base regulation (Study #3) at rest and during upright cycling at intensities above and below the ventilatory anaerobic threshold (T(vent)). Study #1 is currently in progress and results to date support our hypotheses that cardiac parasympathetic nervous system activity is blunted in the resting state and that sympathetic activity is reduced during strenuous exercise above T(vent) in late gestation. Technical aspects of the study and the testing protocol have been finalized for Study #2 and data collection will begin in January 1998. Study #3 is essentially complete and supports the concept that arterialized plasma H+ is lower in the pregnant vs. nonpregnant state. However, changes in H+ induced by standardized strenuous exercise are comparable in the pregnant vs. nonpregnant state. Nonpregnant subjects may have greater reductions in the strong ion difference (SID) in response to exercise above (T(vent)), but this is compensated by a greater respiratory response and a reduced arterial plasma carbon dioxide tension. Our results to date support the hypothesis that healthy physically active women can safely adapt to short bouts of strenuous exercise in late gestation.

Descriptors :   *PREGNANCY, *CARDIOVASCULAR SYSTEM, CONTROL, HUMANS, ACID BASE EQUILIBRIUM, THRESHOLD EFFECTS, INTENSITY, CYCLES, RESPONSE, DATA ACQUISITION, STANDARDIZATION, RESPIRATORY SYSTEM, KINETICS, HYPOTHESES, RESPONSE(BIOLOGY), SYMPATHETIC NERVOUS SYSTEM, AUTONOMIC NERVOUS SYSTEM, OXYGEN CONSUMPTION, EXERCISE(PHYSIOLOGY), ANAEROBIC PROCESSES.

Subject Categories : Medicine and Medical Research

Distribution Statement : APPROVED FOR PUBLIC RELEASE