A longitudinal study of maternal oxygen saturation during short-term submaximal exercise

Assessment of physical fitness during pregnancy: validity and reliability of fitness tests, and relationship with maternal and neonatal health - a systematic review

Objectives

To systematically review studies evaluating one or more components of physical fitness (PF) in pregnant women, to answer two research questions: (1) What tests have been employed to assess PF in pregnant women? and (2) What is the validity and reliability of these tests and their relationship with maternal and neonatal health?

Design

A systematic review.

Data sources

PubMed and Web of Science.

Eligibility criteria

Original English or Spanish full-text articles in a group of healthy pregnant women which at least one component of PF was assessed (field based or laboratory tests).

Results

A total of 149 articles containing a sum of 191 fitness tests were included. Among the 191 fitness tests, 99 (ie, 52%) assessed cardiorespiratory fitness through 75 different protocols, 28 (15%) assessed muscular fitness through 16 different protocols, 14 (7%) assessed flexibility through 13 different protocols, 45 (24%) assessed balance through 40 different protocols, 2 assessed speed with the same protocol and 3 were multidimensional tests using one protocol. A total of 19 articles with 23 tests (13%) assessed either validity (n=4), reliability (n=6) or the relationship of PF with maternal and neonatal health (n=16).

Conclusion

Physical fitness has been assessed through a wide variety of protocols, mostly lacking validity and reliability data, and no consensus exists on the most suitable fitness tests to be performed during pregnancy.

PROSPERO registration number

CRD42018117554.

Blood oxygenation response to aerobic exercise combined with breathing exercises in pregnant women: a randomized controlled trial

Background

There are many physiological changes occur during pregnancy that affect oxygenation of the pregnant women. It was considered that aerobic and breathing exercises are safe for the mother and the fetus especially moderate intensity exercise during pregnancy.

Objective

This study was designed to investigate the blood oxygenation response to aerobic exercise combined with breathing exercises in pregnant women.

Methodology

Forty pregnant women were selected from obstetrics and gynecology outpatient clinic at Kasr El Einy Hospital, Egypt, confidentiality was assured. They were ranged from 25 to 30 years old, with body mass index (BMI) less than 30 kg/m2 and at the beginning of 3rd trimester, this study was conducted from September 2019 to April 2020. They were assigned into two groups: group A performed aerobic exercise in a form of walking for 20 min. On the treadmill at 60–75% of the maximum heart rate (MHR) of each woman, three times per week in addition to deep breathing exercises in form of diaphragmatic and lateral costal breathing; group B who performed deep breathing exercises only in form of diaphragmatic and lateral costal breathing. The program continued for three months, three times per week. The oxygen saturation (SaO2) was measured twice time, firstly, at the beginning of 3rd trimester of pregnancy then after three months of treatment program.

Results

The results of this study revealed a statistically significant difference in the oxygen saturation in group A than in group B.

Conclusion

It could be concluded that there was significant statistical effect of aerobic exercise combined with breathing exercises on blood oxygenation in pregnant women. It improved the oxygen saturation in pregnant women.

Low-impact exercise during pregnancy - a study of safety

BACKGROUND

Exercise is an important part of many women's lives. Women are often advised to refrain from physical exercise during pregnancy. The reason given is mainly safety, i.e. fear of maternal hyperthermia, which is known to be related to neural tube defects. However, exercise during pregnancy has not been shown to be related to hyperthermia.

OBJECTIVE

To study temperature and oxygen saturation responses to low-impact exercise in healthy pregnant women.

METHODS

Forty pregnant women and 11 controls participating in low-impact aerobic exercise were monitored before exercise, at maximum-exercise level, and after exercise with regard to core temperature, heart rate, and oxygen saturation level.

RESULTS

The core temperature among the pregnant women did not increase significantly at maximum exercise or after exercise (36.5 versus 36.7 or 36.5 degrees C, P = 0.1, P = 0.5). None of the pregnant women were even close to approaching a dangerous body temperature at an intensity level of 69% of their maximum heart rate. As compared with pre-exercise values, oxygen saturation among pregnant women was significantly reduced at both maximum-exercise and postexercise measurements, but no measurement was below 95% in oxygen saturation.

CONCLUSION

Low-impact aerobics at about 70% of one's maximum heart rate appears to be safe in terms of risk of maternal hyperthermia.

Physiological Basis for Recommendations Regarding Exercise during Pregnancy at High Altitude

Although exercise during pregnancy has been shown to be safe and is now recommended by the American College of Obstetricians and Gynecologists and the Society of Obstetricians and Gynaecologists of Canada for all healthy women, little is known about the combined effects of high altitude and exercise during pregnancy. Due to a paucity of experimental data, recommendations regarding exercise during pregnancy at elevations >/=1600 m must be based on synthesis of available information regarding the independent effects of high altitude and exercise on uteroplacental oxygen delivery. Maternal hyperventilation and elevated blood hemoglobin concentration maintain resting arterial oxygen content at or above sea-level values. During exercise, however, arterial hemoglobin saturation falls, lowering the oxygen content. Resting uterine artery blood flow is lower in residents at 3100 m than at 1600 m, and flow is likely to decrease further during exercise, in proportion to the intensity and duration. The combined reduction in arterial oxygen content and uterine artery flow suggest that fetal oxygen delivery is compromised during exercise at altitude. Anemia, which should be defined according to altitude-adjusted criteria, will further diminish oxygen delivery. Clinicians may wish to monitor patient hemoglobin concentration more frequently and adopt a more conservative stance regarding exercise during pregnancy for both residents and visitors of altitudes >/=1600 m.