Effects of human pregnancy and aerobic conditioning on alveolar gas exchange during exercise
- 1 July 2005
- journal article
- research article
- Published by Canadian Science Publishing in Canadian Journal of Physiology and Pharmacology
- Vol. 83 (7), 625-633
- https://doi.org/10.1139/y05-054
Abstract
This study examined the effects of aerobic conditioning during the second and third trimesters of human pregnancy on ventilatory responses to graded cycling. Previously sedentary pregnant women were assigned randomly to an exercise group (n = 14) or a nonexercising control group (n = 14). Data were collected at 15–17 weeks, 25–27 weeks and 34–36 weeks of pregnancy. Testing involved 20 W·min–1 increases in work rate to a heart rate of 170 beats·min–1 and (or) volitional fatigue. Breath-by-breath ventilatory and alveolar gas exchange measurements were compared at rest, a standard submaximal [Formula: see text]O2 and peak exercise. Within both groups, resting [Formula: see text]E, [Formula: see text]A, and VT/TI increased significantly with advancing gestation. Peak work rate, O2 pulse [Formula: see text]O2/HR, [Formula: see text]E, [Formula: see text]A respiratory rate, VT/TI, [Formula: see text]O2, [Formula: see text]CO2, and the ventilatory threshold (Tvent) were increased after physical conditioning. Chronic maternal exercise has no significant effect on pregnancy-induced changes in ventilation and (or) alveolar gas exchange at rest or during standard submaximal exercise. Training-induced increases in Tvent and peak oxygen pulse support the efficacy of prenatal fitness programs to improve maternal work capacity. Key words: human gestation, respiration, chronic exercise.Keywords
This publication has 21 references indexed in Scilit:
- Joint SOGC/CSEP Clinical Practice Guideline: Exercise in Pregnancy and the Postpartum PeriodCanadian Journal of Applied Physiology, 2003
- The effect of endurance training on the ventilatory response to exercise in elite cyclistsEuropean Journal of Applied Physiology, 2000
- Normal Cardiopulmonary Physiology During PregnancyClinical Obstetrics and Gynecology, 1996
- Relationship between inspiratory effort and breathlessness in pregnancyJournal of Applied Physiology, 1991
- Ventilatory Drive and Respiratory Muscle Function in PregnancyAmerican Review of Respiratory Disease, 1991
- Alignment of ventilation and gas fraction for breath-by-breath respiratory gas exchange calculations in exerciseComputers and Biomedical Research, 1991
- Pulmonary and ventilatory responses to pregnancy, immersion, and exerciseJournal of Applied Physiology, 1989
- Mediation of reduced ventilatory response to exercise after endurance trainingJournal of Applied Physiology, 1987
- A new method for detecting anaerobic threshold by gas exchangeJournal of Applied Physiology, 1986
- Breath-by-breath measurement of true alveolar gas exchangeJournal of Applied Physiology, 1981