Background: Physical activity (PA) during pregnancy is an effective and safe way to improve maternal health in uncomplicated pregnancies. However, compliance with PA recommendations remains low among pregnant women. Objective: The purpose of this study was to evaluate the effects of offering structured supervised exercise training (EXE) or motivational counseling on PA (MOT) during pregnancy on moderate-to-vigorous intensity physical activity (MVPA) level. Additionally, complementary measures of PA using the Pregnancy Physical Activity Questionnaire (PPAQ) and gold standard doubly labeled water (DLW) technique were investigated. The hypotheses were that both EXE and MOT would increase MVPA in pregnancy compared with standard care (CON) and that EXE would be more effective than MOT. In addition, the association between MVPA and the number of sessions attended was explored. Methods: A randomized controlled trial included 220 healthy, inactive pregnant women with a median gestational age of 12.9 (IQR 9.4-13.9) weeks. A total of 219 women were randomized to CON (45/219), EXE (87/219), or MOT (87/219). The primary outcome was MVPA (minutes per week) from randomization to the 29th gestational week obtained by a wrist-worn commercial activity tracker (Vivosport, Garmin International). PA was measured by the activity tracker throughout pregnancy, PPAQ, and DLW. The primary outcome analysis was performed as an analysis of covariance model adjusting for baseline PA. Results: The average MVPA (minutes per week) from randomization to the 29th gestational week was 33 (95% CI 18 to 47) in CON, 50 (95% CI 39 to 60) in EXE, and 40 (95% CI 30 to 51) in MOT. When adjusted for baseline MVPA, participants in EXE performed 20 (95% CI 4 to 36) minutes per week more MVPA than participants in CON (P=.02). MOT was not more effective than CON; EXE and MOT also did not differ. MVPA was positively associated with the number of exercise sessions attended in EXE from randomization to delivery (P=.04). Attendance was higher for online (due to COVID-19 restrictions) compared with physical exercise training (P=.03). Adverse events and serious adverse events did not differ between groups. Conclusions: Offering EXE was more effective than CON to increase MVPA among pregnant women, whereas offering MOT was not. MVPA in the intervention groups did not reach the recommended level in pregnancy. Changing the intervention to online due to COVID-19 restrictions did not affect MVPA level but increased exercise participation. Trial Registration: ClinicalTrials.gov NCT03679130; https://clinicaltrials.gov/ct2/show/NCT03679130 International Registered Report Identifier (IRRID): RR2-10.1136/bmjopen-2020-043671

Postpartum physical activity (PA) is linked to improved mental health and sleep. Yet, many women do not return to pre-pregnancy PA levels, and sedentary behavior may increase. This study mapped PA, sedentary time, and sleep from early pregnancy to one year postpartum, and examined if prenatal PA interventions affect these outcomes postpartum. In the FitMum randomized controlled trial, 220 healthy, inactive pregnant women (< 15 + 0 weeks gestation) were assigned to standard care (CON), supervised exercise (EXE), or motivational PA counselling (MOT). Participants wore wrist-worn activity trackers from inclusion to one year postpartum and completed the Pregnancy Physical Activity Questionnaire and Pittsburgh Sleep Quality Index. We found that postpartum daily steps increased by ~ 2,000 compared to late pregnancy (p < 0.001), while moderate-to-vigorous-intensity PA (MVPA) declined (p < 0.001). Sedentary time remained similar. Sleep duration dropped postpartum in the first three months (p < 0.05), while sleep quality improved (p = 0.006). Prenatal PA interventions had minimal impact postpartum, however, EXE participants reported slightly better sleep than MOT at one year. In conclusion, PA patterns and sleep changed postpartum, with more daily steps, less MVPA, and reduced sleep duration. Prenatal PA interventions had limited effect. Longitudinal studies are needed to optimize timing of interventions for maternal health. The study is registered at ClinicalTrials.gov; NCT03679130;20/09/2018.

BACKGROUND Physical activity (PA) during pregnancy is an effective and safe way to improve maternal health in uncomplicated pregnancies. However, compliance with PA recommendations remains low among pregnant women. OBJECTIVE The purpose of this study was to evaluate the effects of offering structured supervised exercise training (EXE) or motivational counseling on PA (MOT) during pregnancy on moderate-to-vigorous intensity physical activity (MVPA) level. Additionally, complementary measures of PA using the Pregnancy Physical Activity Questionnaire (PPAQ) and gold standard doubly labeled water (DLW) technique were investigated. The hypotheses were that both EXE and MOT would increase MVPA in pregnancy compared with standard care (CON) and that EXE would be more effective than MOT. In addition, the association between MVPA and the number of sessions attended was explored. METHODS A randomized controlled trial included 220 healthy, inactive pregnant women with a median gestational age of 12.9 (IQR 9.4-13.9) weeks. A total of 219 women were randomized to CON (45/219), EXE (87/219), or MOT (87/219). The primary outcome was MVPA (minutes per week) from randomization to the 29th gestational week obtained by a wrist-worn commercial activity tracker (Vivosport, Garmin International). PA was measured by the activity tracker throughout pregnancy, PPAQ, and DLW. The primary outcome analysis was performed as an analysis of covariance model adjusting for baseline PA. RESULTS The average MVPA (minutes per week) from randomization to the 29th gestational week was 33 (95% CI 18 to 47) in CON, 50 (95% CI 39 to 60) in EXE, and 40 (95% CI 30 to 51) in MOT. When adjusted for baseline MVPA, participants in EXE performed 20 (95% CI 4 to 36) minutes per week more MVPA than participants in CON (P=.02). MOT was not more effective than CON; EXE and MOT also did not differ. MVPA was positively associated with the number of exercise sessions attended in EXE from randomization to delivery (P=.04). Attendance was higher for online (due to COVID-19 restrictions) compared with physical exercise training (P=.03). Adverse events and serious adverse events did not differ between groups. CONCLUSIONS Offering EXE was more effective than CON to increase MVPA among pregnant women, whereas offering MOT was not. MVPA in the intervention groups did not reach the recommended level in pregnancy. Changing the intervention to online due to COVID-19 restrictions did not affect MVPA level but increased exercise participation. CLINICALTRIAL ClinicalTrials.gov NCT03679130; https://clinicaltrials.gov/ct2/show/NCT03679130 INTERNATIONAL REGISTERED REPORT RR2-10.1136/bmjopen-2020-043671

Background: Sulfur-containing amino acids (SCAAs) are essential for fetal growth and development, but their metabolism during pregnancy remains poorly understood, with conflicting reports regarding the effect of exercise training. This study investigates the effects of physical activity (PA) interventions on maternal plasma concentrations of SCAAs and their associations with neonatal outcomes. Methods: The FitMum randomized controlled trial included 220 healthy, inactive, pregnant women enrolled before gestation age (GA) 15+0 weeks. Participants were randomized to supervised exercise training (EXE), motivational counseling on PA (MOT), or standard care (CON). This secondary analysis includes all participants with an eligible blood sample (n = 214). Maternal plasma concentrations of SCAAs were measured at four time points (GA ≤15+0, 28+0-6, 34+0-6, and delivery), and umbilical cord venous plasma was measured at delivery. Results: Longitudinally, maternal methionine and taurine concentrations decreased significantly (p < 0.001 for both) during pregnancy, while total cysteine (tCys) concentrations increased (p < 0.001). At GA 28+0-6 weeks, methionine concentrations were significantly higher in EXE (p = 0.031) and MOT (p = 0.006) groups compared to CON, and tCys was higher in the MOT group (p = 0.017) versus CON. Maternal taurine was positively associated with birth weight (p = 0.034) and birth weight/placental weight ratio (p = 0.010), while maternal tCys was negatively associated with head circumference (p < 0.001). Additionally, increased moderate-to-vigorous intensity physical activity (MVPA) was associated with a smaller maternal–umbilical venous difference for methionine (p = 0.025), suggesting enhanced placental transport. Conclusions: Pregnancy significantly alters maternal metabolism of SCAAs. PA interventions may modulate maternal methionine and tCys concentrations, and our results suggest that maternal taurine status is linked to offspring birth weight, highlighting the potential of PA to influence key nutrients required for fetal development.