Final answer:
During pregnancy, there's an increase in maternal blood volume and respiratory minute volume. However, responses such as increased body temperature and baroreceptor firing rates in response to exercise can be different compared to the non-pregnant state due to the body's adaptations to pregnancy. These adaptations, along with digestive and urinary changes, can affect physiologic responses to exercise.
Step-by-step explanation:
When comparing the physiologic responses to acute exercise during pregnancy to those in non-pregnant women, there are several changes and also some elements that remain stable or decrease. During pregnancy, several changes occur including an increase in maternal blood volume by 30 percent and a 50 percent rise in respiratory minute volume to meet the additional oxygen demands of the fetus and the mother's increased metabolic rate. In the context of exercise, these adjustments in nonpregnant individuals ordinarily lead to an increase in body temperature and increased firing rates of baroreceptors in response to the raised blood volume and pressure.
Conversely, during pregnancy, certain responses, such as body temperature, might not increase as they would in a non-pregnant state because the body is already adapting to the pregnancy. Additionally, changes in the circulatory system, such as the decreased firing rates of baroreceptors, alongside decreased epinephrine and norepinephrine release by the adrenal glands during pregnancy may affect how the body responds to exercise compared to the non-pregnant state. Furthermore, the digestive and urinary systems also undergo changes that could lead to decreased digestive activity during acute exercise to allocate resources towards the fetus and the exercise demands. Common discomforts such as nausea, heartburn, and increased frequency of urination can exacerbate the impact of exercise during pregnancy.