Prenatal Exercise and Cardiorespiratory Health and Fitness: A Meta-analysis

Vascular health and exercise in females throughout the lifespan: Exploring puberty, pregnancy and menopause

This narrative review highlights the impact of exercise on vascular health in females over the lifespan with an emphasis on puberty, pregnancy and menopause. These events encompass substantial changes in sex hormone levels, particularly oestrogens and progesterone. They are also accompanied by distinct adaptations of the central, peripheral and cerebral vasculature. Regular exercise is an effective mechanism to reduce vascular risk in females of all ages, especially for those at higher risk for vascular disorders. However, there are large variabilities in the vascular adaptations to exercise in females that may be related to circulating sex hormone levels. In addition, exogenous hormones, such as oral contraceptives taken after puberty or hormonal replacement therapy taken to mitigate symptoms of menopause, may interact with exercise-induced changes in vascular function. We highlight how more research is needed to understand the optimal exercise interventions to promote vascular health in females across the lifespan, especially during times of hormonal transition.

Running for two (or three!): the journey of an ultramarathoner across two pregnancies

There is a lack of evidence regarding the safety of long-duration and vigorous-intensity physical activity during pregnancy, such as that required during an ultramarathon. This case study is the first to examine the training, performance, health, and delivery outcomes for an ultramarathoner across two successive pregnancies (one twin and one singleton) that were delivered when the athlete was 41 and 43 yr, respectively. During her twin pregnancy, she ran an average of 91.72 ± 23.17 km across 9.06 ± 2.38 h/wk. Both twins were normal for gestational age and delivered at 37 wk. Twin 2 experienced mild hypoxic-ischemic encephalopathy but made a full recovery following treatment. Twin pregnancy increases the risk of this complication, and there is no evidence to suggest that it is associated with vigorous-intensity endurance activity. During her singleton pregnancy, the participant's distance and pace increased, running on average 157.80 ± 14.69 km across 14.08 ± 1.60 h/wk. She also competed in five races including three ultramarathons and ranked well, with no adverse events during or following each of the races. She delivered prematurely (36 wk and 6 days), but her baby was normal for gestational age.NEW & NOTEWORTHY This study provides the first description of a pregnant female ultramarathoner's training patterns, performance outcomes, and health and birthing outcomes across two pregnancies.

Cardiovascular effects of exercise training in pregnant people with a high body mass index: secondary results from a randomised controlled trial (ETIP)

Objectives

We aimed to determine the effectiveness of exercise training during pregnancy on peak oxygen uptake (V̇O2peak), cardiac function and flow-mediated dilatation (FMD) of the brachial artery throughout pregnancy and post partum in individuals with a prepregnancy body mass index (BMI) ≥28 kg/m2.

Trial design

Parallel-group randomised controlled trial (RCT).

Methods

The exercise group in the Exercise Training in Pregnancy (ETIP) RCT was offered 3 weekly supervised exercise sessions comprising 35 min of moderate-intensity treadmill walking followed by 25 min of strength exercises. The intervention started in gestational weeks 12-18 and continued throughout pregnancy. We measured V̇O2peak and FMD at baseline, in gestational weeks 34-37 and 3 months post partum and offered echocardiography in gestational weeks 14, 20, and 32, and 6-8 weeks postpartum.

Results

Of the 91 participants included in ETIP, 87 participants (age: 31.3±4.2 years, BMI: 34.6±4.3 kg/m2) provided data on V̇O2peak, cardiac function and/or FMD. There was no statistically significant effect of exercise training on V̇O2peak in gestational weeks 34-37, with an estimated effect of 1.7 mL/min/kg (95% CI -0.4 to 3.7, p=0.112) or post partum (1.6 mL/min/kg, 95% CI -0.2 to 3.4, p=0.079), compared with the control group. There were no statistically significant between-group differences in either FMD or any of the echocardiographic outcomes. Only 50% of the participants in the exercise group fulfilled our prespecified adherence criteria.

Conclusion

Offering pregnant individuals with BMI ≥28 kg/m2, a supervised exercise intervention did not improve cardiorespiratory fitness, cardiac function or FMD.

Trial registration number

NCT01243554.

Maternal physical activity in healthy pregnancy: Effect on fetal oxygen supply

AIM

We review evidence for effects of physical activity before and during gestation on the course of pregnancy and ask if there are circumstances where physical activity can stress the fetus due to competition for oxygen and energy substrates.

RESULTS

We first summarize physiological responses to exercise in nonpregnant people and known physiological adaptations to pregnancy. Comparing the two, we conclude that physical activity prior to and continuing during gestation is beneficial to pregnancy outcome. The effect of starting an exercise regimen during pregnancy is less easy to assess as few studies have been undertaken. Results from animal models suggest that the effects of maternal exercise on the fetus are transient; the fetus can readily compensate for a short-term reduction in oxygen supply.

CONCLUSION

In general, we conclude that physical activity before and during pregnancy is beneficial, and exercise started during pregnancy is unlikely to affect fetal development. We caution, however, that there are circumstances where this may not apply. They include the intensive exercise regimens of elite athletes and pregnancies at high altitudes where hypoxia occurs even in the resting state.

Exercise effects on maternal vascular health and blood pressure during pregnancy and postpartum: a systematic review and meta-analysis

AIMS

This systematic review aimed to assess the effects of exercise training during pregnancy and the postpartum period on maternal vascular health and blood pressure (BP).

METHODS AND RESULTS

The outcome of interest was pulse wave velocity (PWV), flow-mediated dilation (FMD), and BP from pregnancy to 1-year postpartum. Five databases, including Ovid MEDLINE, EMBASE, CINAHL, Web of Science, and Cochrane Library, were systematically searched from inception to August 2023. Studies of randomized controlled trials (RCTs) comparing the effects of prenatal or postpartum exercise to a non-exercise control group were included. The risk of bias and the certainty of evidence were assessed. Random-effects meta-analyses and sensitivity analyses were conducted. In total, 20 RCTs involving 1221 women were included. Exercise training, initiated from Week 8 during gestation or between 6 and 14 weeks after delivery, with the programme lasting for a minimum of 4 weeks up to 6 months, showed no significant impact on PWV and FMD. However, it resulted in a significant reduction in systolic BP (SBP) [mean difference (MD): -4.37 mmHg; 95% confidence interval (CI): -7.48 to -1.26; P = 0.006] and diastolic BP (DBP) (MD: -2.94 mmHg; 95% CI: -5.17 to -0.71; P = 0.01) with very low certainty. Subgroup analyses revealed consistent trends across different gestational stages, types of exercise, weekly exercise times, and training periods.

CONCLUSION

Exercise training during pregnancy and the postpartum period demonstrates a favourable effect on reducing maternal BP. However, further investigations with rigorous methodologies and larger sample sizes are needed to strengthen these conclusions.

Guidelines for assessing maternal cardiovascular physiology during pregnancy and postpartum

Maternal mortality rates are at an all-time high across the world and are set to increase in subsequent years. Cardiovascular disease is the leading cause of death during pregnancy and postpartum, especially in the United States. Therefore, understanding the physiological changes in the cardiovascular system during normal pregnancy is necessary to understand disease-related pathology. Significant systemic and cardiovascular physiological changes occur during pregnancy that are essential for supporting the maternal-fetal dyad. The physiological impact of pregnancy on the cardiovascular system has been examined in both experimental animal models and in humans. However, there is a continued need in this field of study to provide increased rigor and reproducibility. Therefore, these guidelines aim to provide information regarding best practices and recommendations to accurately and rigorously measure cardiovascular physiology during normal and cardiovascular disease-complicated pregnancies in human and animal models.

Physical activity promotion among pregnancy - the role of physician from the women's perspective

Objective

The clear benefits of planned and supervised physical activity (PA) during pregnancy make it imperative that women are encouraged and educated about this activity. This study aimed to investigate how effectively physician promote physical activity and exercise among pregnant women. It also examines pro-health changes in selected health behaviours during pregnancy.

Methods

This cross-sectional study recruited a total of 353 pregnant women in Wielkopolskie Voivodship in Poland. An anonymous survey (on-line or in-paper) was used to assess physical activity before and during pregnancy (with Pregnancy Physical Activity Questionnaire), physical activity self-efficacy, well-being (WHO-5 Well-Being Index), and guidance received from physicians on physical activity during pregnancy.

Results

Only 41% of women surveyed followed WHO recommendations for PA before pregnancy, and they were much more likely to discuss safety and the need to change the intensity or type of PA with their doctor or gynaecologist. Only 23% of women were asked about their PA before pregnancy and less than 40% were encouraged to be active during pregnancy. We observed a higher probability of poor well-being among pregnant women who were inactive before pregnancy (OR = 1.873, 95%CI 1.026 to 3.421, p = 0.041).

Conclusion

Health professionals infrequently educate and motivate women to be physically active during pregnancy. Physician advice, as it is currently perceived by women, seems to be insufficient to help pregnant women meet the recommendations for PA during pregnancy.

Stress is not so bad-cortisol level and psychological functioning after 8-week HIIT program during pregnancy: a randomized controlled trial

Background

Amid extensive pregnancy exercise research, the impact of High Intensity Interval Training (HIIT) on pregnant women's mental health is underexplored. Despite exercise benefits, it can trigger stress responses like elevated cortisol. This study fills the gap by investigating correlations between hair cortisol levels, mental health, and HIIT effects in pregnant women.

Methods

We conducted a randomized control trial among 38 Caucasian women in uncomplicated, singleton pregnancy (age 31.11 ± 4.03 years, 21.82 ± 4.30 week of gestation; mean ± SD). The experimental group comprised 22 women engaged in an 8-week high-intensity interval training program (HIIT). The comparative group consisted of 16 pregnant women undergoing an 8-week educational program (EDU). Before and after the interventions, all women were evaluated using the following tools: Hair cortisol level measurements, Beck Depression Inventory - II for depressive symptoms assessment, Childbirth Attitudes Questionnaire for childbirth fear measurement, 12-item Short Form Health Survey to gage health-related quality of life, International Physical Activity Questionnaire for physical activity level estimation, and a Progressive maximal exercise test to evaluate maternal exercise capacity.

Results

The key finding of our study reveals that women engaged in the HIIT intervention exhibited a distinct cortisol production pattern in contrast to the EDU group practicing standard moderate intensity physical activity. In the HIIT group, there was an increase in hair cortisol levels, while the EDU group showed a notable decrease. Remarkably, HIIT stimulated cortisol production without adversely impacting fear of childbirth and psychophysical condition during pregnancy. In fact, only the HIIT group showed a significant enhancement in mental health.

Conclusion

No links were discovered between hair cortisol levels and the severity of depressive symptoms, psychophysical well-being, or fear of childbirth. Hence, based on our research, employing cortisol levels during pregnancy as an indicator of negative stress or depression risk appears unwarranted.

Can Pre-Pregnancy Body Mass Index and Maternal Exercise Affect Birth and Neonatal Outcomes-A Cross Sectional Study

There has been a dramatic worldwide increase in the prevalence of obesity or overweight and physical inactivity in women of reproductive age. Growing evidence suggests that pre-pregnancy maternal abnormal body mass index (BMI) and lower physical activity level are associated with poor maternal health and perinatal outcomes. The aim of this study was to assess how self-perceived exercise and pre-pregnancy BMI are associated with preterm birth, low birth weight, and type of birth. We conducted a retrospective cross-sectional study of 394 Polish women in the postpartum period. We used a questionnaire with the structure of the medical interview. To analyze factors related to birth outcomes, we used the Pearson's Chi-squared test of independence and odds ratio (OR), with a corresponding 95% confidence interval (CI), followed by a multiple logistic regression. Women who reported being physically active before pregnancy (p = 0.00) and during pregnancy (p = 0.03) were more likely to give birth on time and had a lower incidence of very-premature and extremely premature births compared to inactive women. Importantly, they were more likely to have vaginal birth (p = 0.03). Pre-pregnancy BMI influenced the week of delivery, i.e., inadequate, too-high BMI contributed to an increase in the percentage of premature births [OR (95% CI) = 1.19 (1.06; 1.34)]. The findings indicate that promoting physical activity and weight management remains a priority in public health policy, and women of childbearing age should be encouraged to adopt or maintain an active and healthy lifestyle during pregnancy in order to avoid sedentary- and obesity-associated risks affecting birth and newborns' health.

Moderate intensity exercise in pregnant patients with cardiovascular disease: A pilot study

BACKGROUND

Exercise in pregnancy has proven health benefits, yet the safety of exercise in patients with pre-existing cardiovascular disease (CVD) has not been established. Our aim was to determine the feasibility and safety profile of moderate intensity exercise during pregnancy in patients with CVD, compared with those without CVD.

METHODS

This is a prospective single center pilot study of a moderate intensity exercise regimen, with data collection through wearable fitness trackers and personal exercise logs in pregnant patients with and without pre-existing CVD. The primary outcome was Doppler umbilical artery systolic to diastolic (S/D) ratio measured between 32 and 34 weeks' gestation. The secondary outcomes were adverse maternal and fetal events, trends in wearable fitness tracker data, C-reactive protein levels, and weight changes.

RESULTS

At baseline, the CVD group (62% congenital heart disease) took part in more prepregnancy walking, less weightlifting, and had a higher body mass index compared to the control group, and on average walked 539 fewer steps per day during pregnancy than the control group. Resting heart rate (HR) was found to increase in both groups up to 30 weeks' gestation. The cardiovascular disease group displayed an overall lower exercise intensity, as measured by the ability to increase HR with exercise over resting heart rate 1 hour prior to exercise at study baseline (45% vs 59% P < .001). Umbilical artery S/D ratio was normal in both groups. No differences were seen in adverse events between groups.

CONCLUSIONS

This pilot study of moderate intensity exercise in pregnant individuals with pre-existing CVD demonstrated that patients with CVD were not able to increase their HR during exercise throughout pregnancy compared to those in the control group. Although a small study group, this data supports the hypothesis that exercise interventions during pregnancy for patients with CVD are feasible without evidence abnormal fetal Doppler profiles. Further studies using wearable fitness trackers may provide the opportunity to understand how to safely tailor exercise programs to pregnant individuals with CVD.

Effects of 8-Week Online, Supervised High-Intensity Interval Training on the Parameters Related to the Anaerobic Threshold, Body Weight, and Body Composition during Pregnancy: A Randomized Controlled Trial

We aimed to assess the effects of an 8-week, online high-intensity interval training (HIIT) program on the parameters related to the anaerobic threshold (AT), body weight, and body composition in pregnant women. A total of 69 Caucasian women with an uncomplicated singleton pregnancy (age: 31 ± 4 years; gestational age: 22 ± 5 weeks; mean ± standard deviation) were randomly allocated to either an 8-week HIIT program (HIIT group) or to a comparative 8-week educational program (EDU group). Our most important finding was that even with the 8-week progression of pregnancy and physiological weight gain, the HIIT group maintained the same level of parameters related to AT: volume of oxygen at the AT (VO2/AT), percentage of maximal oxygen uptake at the AT (%VO2max/AT), and heart rate at the AT (HR/AT). In contrast, in the EDU group we observed a substantial deterioration of parameters related to the AT. The HIIT intervention substantially reduced the fat mass percentage (median: 30 to 28%; p < 0.01) and improved the total fat-free mass percentage (median: 70% to 72%; p < 0.01). In the EDU group, the body composition did not change significantly. An online, supervised HIIT program may be used to prevent the pregnancy-related risk of excessive weight gain and reduction in exercise capacity without yielding adverse obstetric or neonatal outcomes.

The intergenerational effects of parental physical activity on offspring brain and neurocognition in humans: A scoping review

Animal models suggest physical activity (PA) has intergenerational effects on brain health and neurocognition. This scoping review compiles the human literature in this area, identifies knowledge gaps, and makes recommendations for future research. We systematically searched for experimental or observational studies conducted in humans, published in English, and reporting parental PA exposure (preconception or prenatal) and subsequent offspring brain and neurocognition. Two reviewers independently screened studies according to predetermined inclusion criteria. Fourteen studies were included (four experimental and 10 observational) reporting on 93,486 parent-child dyads (100% maternal, 0% paternal). Prenatal maternal PA exposure was examined in 10 (71%) studies, while preconception and prenatal PA exposure was examined in four (29%) studies. Maternal PA exposure was positively related to offspring (0-20y) brain and neurocognitive development in 25% of experimental studies and 100% of observational studies. Little is known about the intergenerational effects of parental PA on offspring brain and neurocognition in humans, particularly paternal preconception PA. More experimental studies with longer offspring follow-up and more objective and/or mechanistic assessments are required.

ACTIVE PREGNANCY: Workshop on Promotion of Physical Activity in Pregnancy for Exercise Professionals

Introduction

A one-day workshop on promotion of physical activity in pregnancy for exercise professionals was delivered during 2021, to 137 participants. The main aim of this workshop was to motivate and prepare exercise professionals for promoting physical activity and implementing prenatal exercise programs, in their respective private or public fitness centers or other physical activity settings.

Methods

The contents of the workshop were focused on six topics based on the "Pregnancy and Postpartum Exercise Specialist" educational standards by EuropeActive and the "Exercise and Physical Activity during Pregnancy and Postpartum" textbook published by Springer. Participants provided feedback on the effectiveness and satisfaction with the workshop.

Results

Overall evaluations from the feedback forms showed that majority of the participants agreed that the workshop achieved its objectives with a major recommendation as to the organization of more short duration workshops, the inclusion of practical sessions, and the separation of the contents addressing the postpartum period.

Discussion

The workshop on promotion of physical activity in pregnancy for exercise professionals was successfully organized and the participants are looking forward for future ones.

Association between Cardiorespiratory Fitness and Hypertensive Disorders of Pregnancy: A Systematic Review and Meta-Analysis

Hypertensive disorders of pregnancy (HDP) are associated with future cardiovascular disease (CVD), which may be mediated by diminished cardiorespiratory fitness (CRF). In this systematic review and meta-analysis, we summarize evidence linking CRF with HDP before, during, and after pregnancy. We searched relevant databases to identify observational or randomized studies that measured CRF (VO2 max or peak, VO2 at anaerobic threshold, or work rate at peak VO2) in women with and without HDP. We pooled results using random effects models. Fourteen studies (n = 2406 women) reporting on CRF before, during, and after pregnancy were included. Before pregnancy, women who developed HDP had lower CRF (e.g., VO2max < 37 vs. ≥37 mL O2/min) than those without HDP (two studies, 811 women). VO2max at 14−18 weeks of pregnancy was marginally lower among women who developed preeclampsia vs. normotensive women (three studies, 275 women; mean difference 0.43 mL/kg/min [95% CI 0.97, 0.10]). Postpartum, there was a trend towards lower VO2peak in women with previous preeclampsia (three studies, 208 women; 0.26 mL/kg/min [−0.54, 0.02]). While exploratory, our findings raise the possibility that CRF can identify women at risk for HDP, and furthermore, that HDP confers a hit to a woman’s cardiorespiratory reserve.

Maternal Exercise Before and During Pregnancy Facilitates Embryonic Myogenesis by Enhancing Thyroid Hormone Signaling

Background: Maternal exercise (ME) improves fetal and offspring muscle development, but mechanisms remain to be established. Since the thyroid hormone (TH) is critical for cell differentiation during embryonic development, we hypothesized that ME elevates TH receptor (THR) signaling in embryos, which promotes embryonic myogenesis. Methods: Female mice were exercised daily on a treadmill or received a daily TH, triiodothyronine (T3) injection. Embryos (embryonic day 12.5 [E12.5]) and P19 cells were used for studying effects of TH on embryonic myogenesis. TH levels in serum and embryos after ME or T3I were analyzed. Expression of TH signaling related genes and myogenic genes was assessed. THRα binding to the promoters of myogenic genes was investigated by chromatin immunoprecipitation-qantitative polymerase chain reaction (ChIP-qPCR). A CRISPR/CAS9 plasmid was utilized to knock out THRα in P19 cells. Results: ME elevated TH levels in both maternal circulation and embryos, which were correlated with enhanced TH signaling and myogenesis. At E12.5, both myogenic determinants (Pax3, Pax7) and myogenic regulatory factors (Myf5, Myod) were upregulated in ME embryos. ME increased THRα content and elevated messenger RNA (mRNA) expression of TH transporter Slc16a2 and deiodinase Dio2. In addition, the THRα binding to the promoters of Pax3/7 was increased. In P19 embryoid bodies, T3 promoted myogenic differentiation, which was abolished by ablating THRα. Furthermore, maternal daily injection of T3 at a level matching exercised mothers promoted embryonic myogenesis. Conclusions: ME promotes TH delivery to the embryos and enhances embryonic myogenesis, which is partially mediated by enhanced TH signaling in ME embryos.

Active Pregnancy: A Physical Exercise Program Promoting Fitness and Health during Pregnancy-Development and Validation of a Complex Intervention

Physical activity during pregnancy is a public health issue. In the view of reproducibility and the successful implementation of exercise interventions, reporting the quality of such study design must be ensured. The objective of this study was to develop and validate a physical exercise program promoting fitness and health during pregnancy. A qualitative methodological study was carried out. For the description of the exercise program, the Consensus on Exercise Reporting Template (CERT) was used. For the validation of the program, the revised guideline of the Criteria for Reporting the Development and Evaluation of Complex Interventions in Health Care (CReDECI2) was followed and went through three stages of development, piloting, and evaluation. The customizable exercise program was designed and validated by exercise and health specialists based on evidence-based, international recommendations and supported by different educational tools to be implemented by qualified exercise professionals in health and fitness settings. A 12-week testing intervention addressing a group of 29 pregnant women was carried out. The program's feasibility was subsequently evaluated by all the pregnant women. The CReDECI2 process guides practitioners and researchers in developing and evaluating complex educational interventions. The presented intervention may assist exercise specialists, health professionals, and researchers in planning, promoting, and implementing a prenatal exercise program.

Can Group Exercise Programs Improve Health Outcomes in Pregnant Women? An Updated Systematic Review

Current scientific evidence supports the recommendation to initiate or continue physical exercise in healthy pregnant women. Group exercise programs have positive effects on improving health, well-being, and social support. In 2015, a systematic review was provided to evaluate the evidence on the effectiveness of group exercise programs in improving pregnant women's and newborns' health outcomes and to assess the content of the programs. This review aims to update this knowledge between 2015 and 2020. The exercise program designs were analyzed with the Consensus of Exercise Reporting Template (CERT) model, the compliance with the current guidelines, and effectiveness in the maternal health and fitness parameters. Three databases were used to conduct literature searches. Thirty-one randomized control trials were selected for analysis. All studies followed a supervised group exercise program including aerobic, resistance, pelvic floor training, stretching, and relaxation sections. Group interventions during pregnancy improved health and fitness outcomes for the women and newborns, although some gaps were identified in the interventions. Multidisciplinary teams of exercise and health professionals should advise pregnant women that group exercise improves a wide range of health outcomes for them and their newborns.

Research on the influence of prenatal exercises on anthropometric and vascular parameters in pregnant women

Introduction/Objective. The frequency of a sedentary lifestyle during pregnancy increases. This contributes to gestational weight gain and has a negative impact on health. This study researched the impact of prenatal exercise on gestational weight gain, blood pressure, and microcirculation in pregnant women who exercised and those who did not exercise. Methods. The study included seventy pregnant women with a normal pregnancy, who attended a psychophysical preparation program for childbirth for eight weeks. The control group (n=35) attended theoretical classes on childbirth, and the experimental group (n=35) attended prenatal exercises as well. Gestational weight gain, blood pressure, and nailfold capillary density were determined and compared between the two groups. Results. Gestational weight gain of 19.94 kg in non-exercising pregnant women was significantly greater than the gestational weight gain of 11.65 kg in pregnant women who exercised. Pregnant women who did not exercise had an increase in systolic (by 15.56 mmHg) and diastolic pressure (by 16.08 mmHg), which is significantly higher compared to pregnant women who exercised. In this group, systolic pressure increased by 2.5 mmHg, while diastolic did not change. A significant difference in the nailfold capillary density at the end of the prenatal program has not been determined. Conclusion. Prenatal exercise of moderate-intensity has a positive effect on gestational weight gain and the level of blood pressure in pregnant women. The nailfold capillary density has not differed significantly after the prenatal program in pregnant women who have exercised and in those who have not.

Response of endothelial function and oxidative stress after supervised aerobic exercise training in formerly preeclamptic women

We sought to investigate effects of aerobic exercise in women with preeclampsia history. 42 women were enrolled. After 16 weeks, we found improvement in endothelial function index and oxidative stress biomarkers in the exercise group. Moreover, the change of endothelial function index was significantly associated with the change of total antioxidant capacity in the exercise group. Our findings showed aerobic exercise improved exercise capacity, endothelial function and oxidative stress in formerly preeclamptic women, and favorable modification of oxidative stress might be a vital pathway of endothelial function's melioration in those women, which deserves further exploration.

Prenatal exercise and cardiovascular health (PEACH) study: impact of acute and chronic exercise on cerebrovascular hemodynamics and dynamic cerebral autoregulation

We performed a randomised controlled trial measuring dynamic cerebral autoregulation (dCA) using a sit-to-stand maneuver before (SS1) and following (SS2) an acute exercise test at 16-20 weeks gestation (trimester 2; TM2) and then again at 34-37 weeks gestation (third trimester; TM3). Following the first assessment, women were randomised into exercise training or control (standard care) groups; women in the exercise training group were prescribed moderate intensity aerobic exercise for 25-40 minutes on 3-4 days per week for 14±1weeks. Resting seated mean blood velocity in the middle cerebral artery (MCAv_mean) was lower in TM3 compared to TM2 but not impacted by exercise training intervention. dCA was not impacted by gestational age, or exercise training during SS1. During SS2, dCA was altered such that there were greater absolute and relative decreases in mean arterial blood pressure (MAP) and MCAv_mean, but this was not impacted by the intervention. There was also no difference in the relationship between the decrease in MCAv_mean compared to the decrease in MAP (%/%), or the onset of the regulatory response with respect to acute exercise, gestational age, or intervention; however, rate of regulation was faster in women in the exercise group following acute exercise (interaction effect, p=0.048). These data highlight the resilience of the cerebral circulation in that dCA was well maintained or improved in healthy pregnant women between TM2 and TM3. However, future work addressing the impact of acute and chronic exercise on dCA in women who are at risk for cardiovascular complications during pregnancy is needed.

The Effects of Physical Activity on Arterial Stiffness during Pregnancy: An Observational Study

The objective of the present study was to investigate the relationship between moderate-to-vigorous physical activity (MVPA) and arterial stiffness in pregnancy. Thirty-nine women participated in this study resulting in 68 measurements in non-pregnant (NP; n=21), first (TM1; n=8), second (TM2; n=20), and third trimesters (TM3; n=19). Compliance, distensibility, elasticity, β-stiffness, and carotid to femoral (central) and carotid to finger (peripheral) pulse wave velocity (PWV) were assessed. MVPA was measured using accelerometry. Multilevel linear regressions adjusted for multiple tests per participant using random effects to generate β coefficients and 95% confidence intervals (CI) were performed. Distensibility, elasticity, β-stiffness, central- and peripheral-PWV did not differ between pregnant and non-pregnant assessments. Carotid artery compliance was higher in TM2 compared to NP. Central PWV (β Coef: -0.14, 95% CI: -0.27, -0.02) decreased from early to mid-pregnancy and increased in late pregnancy. Meeting the MVPA guidelines was significantly associated with central-PWV (Adj. β Coef: -0.34, 95% CI: -0.62, -0.06, p=0.016), peripheral-PWV (Adj. β Coef: -0.54, 95% CI: -0.91, -0.16, p=0.005), and distensibility (Adj. β Coef: -0.001, 95% CI: -0.002, -0.0001, p=0.018), in pregnancy. These results suggest that MVPA may be associated with improved (i.e. reduced) arterial stiffness in pregnancy. Novelty Bullets • Central PWV, distensibility, compliance, elasticity, and ß-stiffness, but not peripheral PWV, exhibited curvilinear relationships with gestational age • Central and peripheral PWV were lower in pregnant women who met the physical activity guidelines of 150 minutes of moderate-to-vigorous physical activity per week.

The Nine Month Stress Test: Pregnancy and Exercise - Similarities and Interactions

Of all physiological systems, the cardiovascular system takes on the most profound adaptation in pregnancy to support fetal growth and development. The adaptations that arise are systemic and involve structural and functional changes that can be observed at the cerebral, central, peripheral, and microvascular beds. This includes, although is not limited to increased heart rate, stroke volume and cardiac output with negligible change to blood pressure, reductions in vascular resistance and cerebral blood flow velocity, systemic artery enlargement, enhanced endothelial function. All of this takes place to accommodate blood volume expansion and ensure adequate fetal and maternal oxygen delivery. In some instances, the demand placed on the vasculature can manifest as cardiovascular maladaptation and thus, cardiovascular complications can arise. Exercise is recommended in pregnancy because of its powerful ability to reduce the incidence and severity of cardiovascular complications in pregnancy. However, the mechanism by which it acts is poorly understood. The first aim of this review is to describe the systemic adaptations that take place in pregnancy. Secondly, this review aims to describe the influence of exercise on these systemic adaptations. It is anticipated that this review can comprehensively capture the extent of knowledge in this area while identifying areas that warrant further investigation.

Prenatal Exercise and Cardiovascular Health (PEACH) Study: Impact on Muscle Sympathetic Nerve (Re)Activity

PURPOSE

Women who develop gestational hypertension have evidence of elevated muscle sympathetic nerve activity (MSNA) in early pregnancy, which continues to rise after diagnosis. Exercise has been shown to play a preventative role in the development of gestational hypertension and has been shown to reduce resting and reflex MSNA in nonpregnant populations. We sought to investigate whether aerobic exercise affected the sympathetic regulation of blood pressure between the second and third trimesters of pregnancy.

METHODS

We conducted a randomized controlled trial of structured aerobic exercise (n = 31) compared with no intervention (control, n = 28) beginning at 16-20 wk and continuing until 34-36 wk of gestation (NCT02948439). Women in the exercise group were prescribed aerobic activity at 50%-70% of their heart rate reserve, on 3-4 d·wk-1 for 25-40 min with a 5-min warm-up and 5-min cool-down (i.e., up to 160 min total activity per week). At preintervention and postintervention assessments, data from ~10 min of quiet rest and a 3-min cold pressor test were analyzed to determine sympathetic nervous system activity and reactivity.

RESULTS

MSNA was obtained in 51% of assessments. Resting MSNA burst frequency and burst incidence increased across gestation (main effect of gestational age, P = 0.002). Neurovascular transduction was blunted in the control group (P = 0.024) but not in exercisers (P = 0.873) at the postintervention time point. Lastly, MSNA reactivity during the cold pressor test was not affected by gestational age or exercise (P = 0.790, interaction).

CONCLUSIONS

These data show that exercise attenuates both the rise in MSNA and the blunting of neurovascular transduction. This may partially explain the lower risk of developing gestational hypertension in women who are active during their pregnancies.

Current Resources for Evidence-Based Practice, March 2021

An extensive review of new resources to support the provision of evidence-based care for women and infants. The current column includes a discussion of men's experiences of pregnancy loss and commentaries on reviews focused on the effects of perineal massage on perineal trauma and air pollution and heat exposure on birth outcomes.

The physiological effect of early pregnancy on a woman's response to a submaximal cardiopulmonary exercise test

Given all its systemic adaptive requirements, pregnancy shares several features with physical exercise. In this pilot study, we aimed to assess the physiological response to submaximal cardiopulmonary exercise testing (CPET) in early pregnancy. In 20 healthy, pregnant women (<13 weeks gestation) and 20 healthy, non-pregnant women, we performed a CPET with stationary cycling during a RAMP protocol until 70% of the estimated maximum heart rate (HR) of each participant. Hemodynamic and respiratory parameters were non-invasively monitored by impedance cardiography (PhysioFlow® ) and a breath-by-breath analyzer (OxyconTM ). To compare both groups, we used linear regression analysis, adjusted for age. We observed a similar response of stroke volume, cardiac output (CO) and HR to stationary cycling in pregnant and non-pregnant women, but a slightly lower 1-min recovery rate of CO (-3.9 [-5.5;-2.3] vs. -6.6 [-8.2;-5.1] L min-1  min-1 ; p = .058) and HR (-38 [-47; -28] vs. -53 [-62; -44] bpm/min; p = .065) in pregnant women. We also observed a larger increase in ventilation before the ventilatory threshold (+6.2 [5.4; 7.0] vs. +3.2 [2.4; 3.9] L min-1  min-1 ; p < .001), lower PET CO2 values at the ventilatory threshold (33 [31; 34] vs. 36 [34; 38] mmHg; p = .042) and a larger increase of breathing frequency after the ventilatory threshold (+4.6 [2.8; 6.4] vs. +0.6 [-1.1; 2.3] breaths min-1  min-1 ; p = .015) in pregnant women. In conclusion, we observed a slower hemodynamic recovery and an increased ventilatory response to exercise in early pregnancy.