Emilie Frederikke Mass Dalhaug

• Haakstad, Lene Annette Hagen; Kissel, Iselin Haugland & Dalhaug, Emilie Frederikke Mass (2026). What is the Influence of Prenatal Physical Activity on Body Weight, BMI, and Health Behavior in Seven-Year-Old Children? Translational Sports Medicine (TSM). 2026. doi: 10.1155/tsm2/3876111. Full text in Research Archive Show summary

  Objectives: To investigate the efects of a prenatal exercise intervention on ofspring body weight, body mass index (BMI), andlifestyle variables at 7 years of age. Methods: Out of 105 physically inactive participants initially randomized to either a physical activity intervention or controlgroup, 80 women and their children (76.2%) participated in this follow-up study. The intervention consisted of intensive physicalactivity counseling and supervised, group-based moderate-intensity exercise sessions during the second and third trimesters ofpregnancy, while the control group received standard prenatal care only. Data were collected via a standardized telephone in-terview with the mother and included the ofspring’s body weight and height, physical activity level, sports participation, andadherence to general health recommendations regarding screen time and diet. Diferences between groups were examined usingtwo-sided independent sample t-tests or chi-squared tests as appropriate. Results: Mean BMI was similar in both groups (intervention group: n = 40; control group: n = 40), but the intervention group had fewer children with overweight/obesity (1 vs. 4) and underweight (3 vs. 6) than the control group. There was a nonsignificant trend toward increased physical activity among the offspring of the intervention group compared with the control group. This was reflected in a higher number following guidelines (≥ 60 min of daily moderate-to-vigorous physical activity [MVPA] according to WHO recommendations) (97.5% vs. 87.5%), number of bouts of MVPA per week (6.4 ± 3.8 vs. 5.8 ± 2.3), and daily hours of MVPA in both summer and winter seasons (2.4 ± 1.3 vs. 2.2 ± 1.3 and 1.6 ± 1.0 vs. 1.4 ± 1.0). The intervention group also reported higher rates of active school transportation than the control group (72.5% vs. 57.5%). No differences were observed in sedentary screen time and diet between the groups. Conclusions: Our results suggest that the intervention may have positively infuenced the BMI status and physical activity levelsof the ofspring.

• Dalhaug, Emilie Frederikke Mass; Sanda, Birgitte; Bø, Kari; Brown, Wendy & Haakstad, Lene Annette Hagen (2025). Pushing limits: the acute effects of a heavy-load resistance protocol and supine exercise on fetal well-being. BMJ Open sport & exercise medicine. 11(3), p. 1–8. doi: 10.1136/bmjsem-2025-002639. Full text in Research Archive Show summary

  Objectives To explore the acute effects of a heavy-load resistance protocol and exercise in the supine position on fetal heart rate (FHR) and uteroplacental blood flow. Method In this experimental laboratory study, 48 healthy pregnant athletes (elite: n=7; recreational: n=41) completed 3×8 repetitions with one repetition in reserve in sumo deadlift, bench press and incline bench press. FHR and umbilical and uterine artery pulsatility index (PI) were assessed before and after exercise. Symptoms of vena cava syndrome were recorded following the supine exercise. Results Pre- and post-exercise FHR remained within the normal range (110–160 bpm), but there were statistically significant increases after sumo deadlifts (p=0.002) and incline bench press (p=0.008), with no significant change after bench press (p=0.122). Umbilical artery PI did not change, while uterine artery PI significantly decreased after the sumo deadlift (p=0.005), bench press (p<0.001) and incline bench press (p<0.001). No fetal bradycardia was observed after the sumo deadlift or incline bench press, but one case occurred after bench press, resolving shortly after 3 min. Fetal tachycardia (>160 bpm) occurred in four cases after sumo deadlift, five after bench press and three after incline bench press, though none exceeded pathological levels (>180 bpm). One recreational athlete experienced symptoms of vena cava syndrome after the supine exercise, coinciding with a slight decrease in umbilical artery PI, but with stable FHR. Conclusion The results indicate that highly active women, especially those with resistance training experience, can safely engage in a heavy-load resistance protocol, including supine exercise, without jeopardising fetal well-being.

• Dalhaug, Emilie Frederikke Mass; Sanda, Birgitte; Bø, Kari; Brown, Wendy J.; Sundgot-Borgen, Jorunn & Haakstad, Lene Annette Hagen (2025). Exceeding the guidelines: A descriptive study of exercise, pregnancy, maternal and neonatal health outcomes in elite and recreational athletes. BMC Pregnancy and Childbirth. 25(1). doi: 10.1186/s12884-025-07572-6. Full text in Research Archive Show summary

  Background Exercise during pregnancy is associated with numerous health benefits. However, guidelines for elite and recreational athletes, who often exceed general recommendations regarding intensity, duration, and frequency are lacking, and potential risks remain unclear. The aim of the study was to describe exercise levels, pregnancy, and maternal and neonatal health outcomes in elite and recreational athletes. Method This study was part of the Strong Mama research project, which was carried out in Oslo, Norway, between October 2022 and February 2024. Sixty athletes (10 elite and 50 recreational) participated in the study. They completed an online survey during late pregnancy and participated in a structured telephone interview six weeks postpartum. The survey and interview collected data on exercise habits, pregnancy experiences, and maternal and neonatal health outcomes. Results The athletes maintained high exercise levels during pregnancy, with elite athletes exercising an average of 11.6 h per week (SD 3.2) and recreational athletes exercising 7.0 h per week (SD 2.4). Most athletes resumed exercising within six weeks postpartum. Almost all pregnancies were planned, including six which involved fertility treatment. Most women (76.7%) had spontaneous onset of labor and vaginal deliveries to term (between 36 and 42 weeks). The mean birthweight was 3487 (SD 519.4, range 2600–4775) grams. Two of the elite athletes were diagnosed with gestational diabetes mellitus and two with hypertension during pregnancy. None of the 50 recreational athletes reported any pregnancy complications. Conclusion High levels of exercise during pregnancy did not seem to negatively impact maternal or neonatal health in this descriptive sample of Norwegian elite and recreational athletes. However, more research is needed to confirm these findings

• Dalhaug, Emilie Frederikke Mass; Sanda, Birgitte; Bø, Kari; Brown, Wendy J.; Øvstedal, Kaia & Brevik-Persson, Anna Sofia [Show all 7 contributors for this article] (2025). Is fetal well-being jeopardised during high-intensity interval training? BMJ Open sport & exercise medicine. 11(2). doi: 10.1136/bmjsem-2025-002496. Full text in Research Archive Show summary

  Objectives: To explore the acute effects of highintensity interval training on fetal heart rate (FHR) and uteroplacental blood flow. Method: Elite (n=10) and recreational athletes (n=50) participated in an experimental laboratory study involving 5×5min intervals of high-intensity exercise on both a treadmill and cycle ergometer, with a 4min pause between intervals for measurement of FHR and uteroplacental blood flow. Target intensity was 17 on Borg’s rating of perceived exertion (RPE) scale and 90% of estimated maximal maternal heart rate (MHRmax). Results: Mean exercise intensity was 16.4 (SD 1.0) RPE and 89.4 (SD 3.8) % of MHRmax during running and 16.0 (SD 1.0) RPE and 84.6 (SD 5.0) % of MHRmax during cycling. Mean FHR was 140.9 (SD 27.4) beats per minute (bpm) during pauses between running bouts and 148.9 (SD 16.0) bpm during pauses between cycling bouts. Six cases of prolonged fetal bradycardia (3min) occurred during running, leading to the termination of exercise. The mothers exercised at 17–18 on Borg’s RPE scale and 86.4%–92.6% of MHRmax in these cases. All cases were normalised within 8min of ending the protocol. There were no cases of prolonged fetal bradycardia during cycling. Exercise was terminated for three women during running and two women during cycling due to fetal tachycardia (≥180 bpm for >4min during rest). Conclusion: Despite cases of fetal bradycardia and tachycardia, our results indicate that highly active women can engage in multiple intervals of high-intensity interval training without apparent harm to fetal well-being.

• Marken, Marlene Zahl; Dalhaug, Emilie Frederikke Mass; Thing, Lone Friis; Abrahamsen, Frank Eirik; Bø, Kari & Haakstad, Lene Annette Hagen (2025). Experiences and perspectives on pregnancy and motherhood in elite athletes–a qualitative study. Sexual and Reproductive Health Matters (SRHM). 33(1), p. 1–16. doi: 10.1080/26410397.2025.2501832. Full text in Research Archive Show summary

  Elite athletes routinely undertake strenuous training routines, which often involve high-intensity sessions. However, there are knowledge gaps in how they experience training during pregnancy and subsequent return to sport. Combined with inadequate financial and contractual safety, female athletes may jeopardise their careers when starting families. This study aimed to describe female athletes’ experiences and perspectives related to pregnancy and motherhood within the context of elite sports in Norway. We interviewed five world-class athletes between October 2022 and April 2023, using a descriptive qualitative approach. Full interview transcripts were analysed based on a reflexive thematic analysis model. Five overarching themes were identified: (1) uncertainty, (2) lack of supportive networks, (3) physical capacity, (4) the impact of postpartum return to sports on maternal health, and (5) combining motherhood and elite sports. Our findings emphasise the challenges that Norwegian pregnant and postpartum athletes face in balancing motherhood with successful careers, highlighting the importance of providing adequate support systems to ensure their health and the well-being of their child.

• Brevik-Persson, Sofia; Gjestvang, Christina; Dalhaug, Emilie Frederikke Mass; Sanda, Birgitte; Melau, Jørgen & Haakstad, Lene Annette Hagen (2024). Cool mama: Temperature regulation during high-intensity interval running in pregnant elite and recreational athletes. Journal of Exercise Science and Fitness. ISSN 1728-869X. 22(4), p. 429–437. doi: 10.1016/j.jesf.2024.09.003. Full text in Research Archive Show summary

  Background/Objective: Regular exercise during pregnancy is beneficial, but athletes often exceed the recommended 150 min of moderate-intensity activity, incorporate high-intensity exercises. The upper limit for exercise intensity and duration on fetal and maternal safety remains uncertain. A concern is a maternal core body temperature of >39.0 °C, potentially increase the risk of heat-related fetal malformations and complications during pregnancy. Blood flow redirection for thermoregulation could compromise fetal cardiovascular function, increasing the risk of miscarriage and preterm labor. This study evaluated whether pregnant women (gestational weeks 25–35) were at risk of exceeding a core body temperature of 39.0 °C during high-intensity running. We also investigated effects on skin temperature, fluid loss, and thermal sensation, comparing pregnant athletes to non-pregnant controls. Methods: In this comparative cross-sectional study, 30 elite and recreational athletes (pregnant n = 15) completed up to five high-intensity treadmill-intervals. Core and skin temperature were continuously measured. Body weight was utilized to calculate the amount of fluid loss. Results: Highest core body temperature were 38.76 °C and 39.56 °C in one pregnant and non-pregnant participant, respectively. Pregnant participants had lower core body temperatures (mean difference −0.47 °C, p ≤ 0.001) initially and a smaller increase (0.10 °C, p ≤ 0.003) during later intervals compared with the non-pregnant controls. Pregnant participants also showed a greater increase in skin temperature (4.08 ± 0.72 °C vs. 3.25 ± 0.86 °C, p = 0.008) and fluid loss (0.81 ± 0.19 L vs. 0.50 ± 0.12 L, p˂0.001). Conclusion: Physiological changes in pregnancy may enhance thermoregulation, indicating that high-intensity interval runs are unlikely to pose a risk of exceeding a core body temperature of 39 °C for pregnant athletes.

• Gjestvang, Christina; Olsen, Malin Landro; Dalhaug, Emilie Frederikke Mass & Haakstad, Lene Annette Hagen (2024). Rating of perceived exertion as a tool for managing exercise intensity during pregnancy: a scoping review. BMJ Open. 14(10). doi: 10.1136/bmjopen-2024-086682. Full text in Research Archive Show summary

  Objective: During pregnancy, international guidelines recommend ≥150 min of moderate-intensity aerobic physical activity per week, with an intensity perceived as fairly light to somewhat hard on the Borg Rating of Perceived Exertion (RPE) scale (ranging from 6 ‘no exertion’ to 20 ‘maximal exertion’, corresponding to 60% to 80% of maximum heart rate). However, the determination and monitoring of exercise intensity seem to be a particular source of confusion, and the most effective method to monitor exercise intensity remains uncertain. This study aimed to examine existing research on the correlation between the Borg RPE scale and maternal heart rate (MHR) for monitoring exercise intensity during pregnancy. Design: Scoping review using the mixed methods appraisal tool (MMAT) and the Grading of Recommendations, Assessment, Development and Evaluations (GRADE) approach. Data sources: PubMed, Web of Science and SPORTDiscus were searched from 16–17 April 2023, with a subsequent search on 1 November 2023. Eligibility criteria: We included studies investigating the correlation between perceived intensity on the Borg RPE scale (6–20) and MHR during exercise in pregnant individuals and written in English/Scandinavian language. There were no restrictions on publication year or study design. Data extraction and synthesis: Two independent reviewers screened the articles based on title and abstract. Selected articles were read in full text and reference lists of screened articles were also checked. Out of 120 studies screened, six articles met the inclusion criteria after removing one duplicate. The results were qualitatively summarised to provide an overview of common themes and variations between studies. MMAT and GRADE assessed the risk of bias and the certainty of the evidence. Results: The six studies involved a total of 260 healthy pregnant individuals (gestational week: from 16 to 38), with various exercise protocols (cycling, walking, running and resistance exercise) and intensities (from light to moderate). Three studies supported the Borg RPE scale to estimate exercise intensity during pregnancy, while three found no correlation between this scale and MHR. The certainty of the evidence was graded as low to moderate, with a potential risk of bias due to small sample sizes, incomplete outcome data and inconsistencies across studies. Conclusion: The mixed results highlight the complexity of monitoring exercise intensity during pregnancy. Using both the Borg RPE scale and MHR might be better than using them separately for monitoring exercise intensity during pregnancy. Due to limited and inconsistent research, more extensive studies are needed.

• Haakstad, Lene Annette Hagen; Benvenuti, Maria Beatrice; Dalhaug, Emilie Frederikke Mass & Bø, Kari (2023). Lumbopelvic pain and sick leave during pregnancy: A comparison of Italy and Norway. Women's Health. ISSN 1745-5057. 19. doi: 10.1177/17455057231218197. Full text in Research Archive Show summary

  Background: Pregnancy-related lumbopelvic pain is a frequently reported musculoskeletal disorder, but few studies have compared data between countries. Objectives: Examine prevalence, severity, and sick leave and explore potential risk factors associated with pregnancy-related lumbopelvic pain in Italian women and compare the results to a similar study in Norway, utilizing the same questionnaire. Design: Cross-sectional Methods: Italian (n = 481) and Norwegian women (n = 435) were allocated from two public hospitals in Rome (Fatebenefratelli San Giovanni Calibita-Isola Tiberina) and Oslo (Oslo University Hospital), as well as four antenatal clinics in Modena (Italy). The questionnaire was completed between gestation weeks 32 and 36, addressing women’s experiences of pregnancy-related lumbopelvic pain and sick leave in current week, and retrospectively for prepregnancy, first and second trimesters. Results: In Italy and Norway, 39% and 57% of pregnant women reported pregnancy-related lumbopelvic pain, respectively, with 11% and 25% experiencing severe pregnancy-related lumbopelvic pain. Pregnancy-related lumbopelvic pain was associated with sick leave in Norway (p < 0.01), but not in Italy (p = 0.66) at late gestation. In both countries, women with pregnancy-related lumbopelvic pain versus those with no pregnancy-related lumbopelvic pain were more likely to be multiparous (Italy: 40% versus 31%, p = 0.06 and Norway: 53% versus 38%, p < 0.01), and have gestational weight gain above guidelines (Italy: 21% versus 13%, p = 0.02% and Norway: 27% versus 14%, p < 0.01) and previous experience of pregnancy-related lumbopelvic pain (Italy: 15% versus 2%, p < 0.01 and Norway: 31% versus 4%, p < 0.01). Maternal exercise (⩾2 times weekly) was associated with less pregnancy-related lumbopelvic pain (Italy: odds ratio = 0.33, 95% confidence interval = 0.11–1.0, p = 0.05 and Norway: odds ratio = 0.55, 95% confidence interval = 0.29–1.0, p = 0.06). Conclusion: We observed high rates of pregnancy-related lumbopelvic pain in Italy and Norway, with Norwegian women reporting the highest prevalence and severity level. While both countries had similar rates of sick leave in late gestation, an association between pregnancy-related lumbopelvic pain and sick leave was observed among Norwegian women only. Health care providers should be proactive in addressing pregnancy-related lumbopelvic pain through open communication and seeking input from pregnant individuals. However, it is essential to acknowledge that the current evidence on effective treatments remains limited and inconclusive, highlighting the need for further research in this field.

• Dalhaug, Emilie Frederikke Mass & Haakstad, Lene Annette Hagen (2022). Does Appearance Matter during Pregnancy? A Cross-Sectional Study of Body Satisfaction from Pre-Pregnancy to Late Gestation. International Journal of Environmental Research and Public Health (IJERPH). ISSN 1661-7827. 19(23). doi: 10.3390/ijerph192316375. Full text in Research Archive Show summary

  Few studies have explored the associations between body satisfaction and physical activity and weight gain during pregnancy, and none have been conducted in Scandinavia. Hence, the aim of the present study was to evaluate changes in body satisfaction from pre-pregnancy to late pregnancy and investigate whether this differed according to parity. We also wanted to explore the association between body satisfaction and physical activity and weight gain among pregnant women in Norway. This cross-sectional survey used an electronic questionnaire to assess physical activity level, weight gain and women’s satisfaction with body weight and size. In total, 150 pregnant women answered the questionnaire. Related-samples Wilcoxon signed rank tests, Mann–Whitney U tests and chi-square tests were used to answer our research questions. The proportion of women who were dissatisfied with their body weight and shape increased from pre-pregnancy to late gestation (body weight p = 0.030 and body shape p = 0.040). Body dissatisfaction before and during pregnancy was linked to weight gain above recommendations. Characterising oneself as physically active prior to pregnancy was associated with satisfaction with body shape pre-pregnancy. Given that mothers strongly influence how a child will judge their body later in life, the results of this study underline the importance of addressing these issues during pregnancy.

• Steene-Johannessen, Jostein; Anderssen, Sigmund Alfred; Kolle, Elin; Hansen, Bjørge Hermann; Bratteteig, Mari & Dalhaug, Emilie Frederikke Mass [Show all 10 contributors for this article] (2021). Temporal trends in physical activity levels across more than a decade – a national physical activity surveillance system among Norwegian children and adolescents. International Journal of Behavioral Nutrition and Physical Activity. 18. doi: 10.1186/s12966-021-01120-z. Full text in Research Archive Show summary

  Background: There is a scarcity of device measured data on temporal changes in physical activity (PA) in large population-based samples. The purpose of this study is to describe gender and age-group specific temporal trends in device measured PA between 2005, 2011 and 2018 by comparing three nationally representative samples of children and adolescents. Methods: Norwegian children and adolescents (6, 9 and 15-year-olds) were invited to participate in 2005 (only 9- and 15-year-olds), 2011 and 2018 through cluster sampling (schools primary sampling units). A combined sample of 9500 individuals participated. Physical activity was assessed by hip worn accelerometers, with PA indices including overall PA (counts per minute), moderate-to-vigorous intensity PA (MVPA), and PA guideline adherence (achieving on average ≥ 60 min/day of moderate-to-vigorous PA). Random-effects linear regressions and logistic regressions adjusted for school-level clusters were used to analyse temporal trends. Findings: In total, 8186 of the participating children and adolescents provided valid PA data. Proportions of sufficiently active 6-year-olds were almost identical in 2011 and 2018; boys 95% (95% CI: 92, 97) and 94% (95%CI: 92, 96) and girls 86% (95% CI: 83, 90) and 86% (95% CI: 82, 90). Proportions of sufficiently active 15-year-olds in 2005 and 2018 were 52% (95% CI: 46, 59) and 55% (95% CI: 48, 62) in boys, and 48% (95% CI: 42, 55) and 44% (95% CI: 37, 51) in girls, respectively, resulting from small differences in min/day of MVPA. Among 9-year-old boys and girls, proportions of sufficiently active declined between 2005 and 2018, from 90% (95% CI: 87, 93) to 84% (95% CI: 80, 87)) and 74% (95% CI: 69, 79) to 68% (95% CI: 64, 72), respectively. This resulted from 9.7 min/day less MVPA in boys (95% CI: − 14.8, − 4.7; p < 0.001) and 3.2 min/day less MVPA (95% CI: − 7.0, 0.7; p = 0.106) in girls. Conclusions: PA levels have been fairly stable between 2005, 2011 and 2018 in Norwegian youth. However, the declining PA level among 9-year-old boys and the low proportion of 15-year-olds sufficiently active is concerning. To evaluate the effect of, and plan for new, PA promoting strategies, it is important to ensure more frequent, systematic, device-based monitoring of population-levels of PA.

• Haakstad, Lene Annette Hagen; Mjønerud, Julie & Mass, Emilie (2020). MAMMA MIA! Norwegian midwives’ practices and views about gestational weight gain, physical activity and nutrition. Frontiers in Psychology. 11. doi: 10.3389/fpsyg.2020.01463. Full text in Research Archive Show summary

  Objectives: Most studies regarding prevalence of prenatal lifestyle counselling are based on patient-report of provider advice. The aim of the present study was to describe midwives’ practice and views in promoting three distinct, but importantly related lifestyle factors: gestational weight gain (GWG), regular physical activity (PA) and nutrition. Design: A cross-sectional study. Setting: Healthcare clinics in Oslo and Akershus County, Norway. Participants: Clinics that expressed interest to participate provided an email list of the midwives. Out of 107 midwives invited to participate, 65 completed the 15-minute electronic survey (SurveyXact), giving a response rate of 60.7%. Outcome measures: We developed a new questionnaire based on questions and results from similar studies, as no validated questionnaires existed when we initiated this project in 2014. The final electronic questionnaire included a mix of close-ended questions, semi close-ended questions and 11-point Likert scales, and covered demographics, personal health behaviors, counselling practice, views and self-perceived role in lifestyle counselling. Results: Mean workload in prenatal care was 78% and mean years practicing was 8.9 (± 7.5). Across all three health-topics, most (74%-95%) reported to give advice on the first meeting, with a mean frequency of 2.2 (± 1.4), 2.7 (± 1.8) and 2.7 (± 2.0) for GWG, PA and nutrition counselling, respectively. About 40% did not report advice on GWG or gave advice discordant with the IOM recommendations (2009) for at least one pre-pregnancy BMI category. GWG was rated as more unpleasant to talk about than PA (3.0±2.8 versus 1.1±2.5, p<0.001) and nutrition (3.0±2.8 versus 1.2±2.5, p = 0.002). Also, regarding the importance of giving lifestyle advice, PA (9.6±0.9 versus 8.3±2.2, p<0.001) and nutrition (9.9±0.4 versus 8.3±2.2, p<0.001) were rated as more important than advice about GWG. Postpartum, nearly 40% gave advice about PA, whereas only two (3.1%) reported to discuss weight/weight retention (p<0.001). Conclusions: While most midwives gave advice on GWG, PA and nutrition at the first meeting, and rated lifestyle counselling as an important topic, the advice on GWG were often discordant with IOM recommendations, and the topic was viewed as more unpleasant to talk about than PA and nutrition.

• Dalhaug, Emilie Mass & Haakstad, Lene Annette Hagen (2019). What the health? information sources and maternal lifestyle behaviors. Interactive Journal of Medical Research. 8(3). doi: 10.2196/10355. Full text in Research Archive Show summary

  Background: Regular physical activity (PA), adequate gestational weight gain (GWG), and healthy eating are important for the long-term health of both mother and baby. Hence, it is important that women receive current and updated advice on these topics and are encouraged to adopt a healthy lifestyle during pregnancy. Objective: The aim of this study was to investigate the main information sources among pregnant women regarding PA, GWG, and nutrition as well as to evaluate how these information sources may affect their health behaviors. Methods: A cross-sectional study design, comprising an electronic questionnaire, was distributed to 2 antenatal clinics, as well as pregnancy-related online chat forums and social media. The inclusion criteria were ≥18 years, ≥20 weeks gestation, and able to read and write Norwegian. In total, 150 pregnant women answered the questionnaire, which was a mix of 11-point Likert scales, close-ended questions, and semi–close-ended questions with the option to elaborate. The relationship between information sources and selected variables, including health behaviors and descriptive variables, were assessed by logistic regression, linear regression, or chi-square as appropriate (P<.05). Results: Mean age (years), gestation week, and prepregnancy body mass index (kg/m2) were 31.1 (SD 4.3), 30.6 (SD 5.9), and 24.2 (SD 4.2), respectively. More than eight out of 10 had received or retrieved information about nutrition (88.7%, 133/150) and PA (80.7%, 121/150), whereas 54.0% (81/150) reported information on GWG. When combining all 3 lifestyle factors, 38.5% had retrieved information from blogs and online forums and 26.6%, from their midwife or family physician. Women who reported the internet and media as their primary source of information on weight gain had increased odds of gaining weight below the Institute of Medicine (IOM) guidelines compared with gaining within the guidelines (odds ratio [OR] 15.5, 95% CI 1.4-167.4; P=.02). Higher compliance with nutritional guidelines was seen among those who cited the internet and media as their main source of information on nutrition (beta=.7, 95% CI 0.07-1.3; P=.03). On the other side, receiving advice from friends and family on weight gain was significantly associated with gaining weight above the IOM guidelines compared with gaining within the guidelines (OR 12.0, 95% CI 1.3-111.7; P=.03). No other associations were found between information sources and health behaviors. Conclusions: The small number of health professionals giving information and the extensive use of internet- and media-based sources emphasize the need to address the quality of internet advice and guide women toward trustworthy sources of information during pregnancy. The association between information sources and PA, GWG, and nutrition requires further research.

• Haakstad, Lene Annette Hagen; Dalhaug, Emilie Mass & Torstveit, Monica Klungland (2018). Fysisk aktivitet i og etter svangerskap. In Torstveit, Monica Klungland; Lohne-Seiler, Hilde; Berntsen, Sveinung & Anderssen, Sigmund Alfred (Ed.), Fysisk aktivitet og helse: Fra begrepsforståelse til implementering av kunnskap. Cappelen Damm Akademisk. ISSN 9788202568313. p. 269–294. Full text in Research Archive

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• Dalhaug, Emilie Frederikke Mass (2026). STRONG MAMA: What happens when pregnant athletes push beyond conventional exercise guidelines?: An experimental and prospective study on maternal and fetal health outcomes. Norges idrettshøgskole. ISSN 9788250206465. Full text in Research Archive Show summary

  Background: Physical activity during pregnancy is associated with numerous maternal and fetal health benefits. While moderate-intensity exercise is widely recommended, the safety of high-intensity exercise, heavy-load resistance training, and high-volume exercise during pregnancy remain unclear. These modalities are often discouraged due to concerns about compromised uteroplacental blood flow and fetal well-being, despite limited empirical evidence. Objective: To investigate the acute effects of high-intensity interval training and a heavy-load resistance protocol, including supine exercise, on fetal heart rate (FHR) and uteroplacental blood flow, and to describe maternal and neonatal health outcomes in elite and recreational athletes. Methods: Pregnant elite (n=10) and recreational (n=50) athletes participated in a cross-sectional experimental study involving 5×5 min intervals of high intensity on both a treadmill and cycle ergometer. Between intervals there was a four min pause for ultrasound measurement of FHR and umbilical and uterine artery pulsatility indices (PI). Target intensity was 17 on Borg’s rating of perceived exertion (RPE) scale and 90% of estimated maximal maternal heart rate (MHRmax). Forty-eight athletes also completed a heavy-load resistance protocol, consisting of 3×8 repetitions with one repetition in reserve in sumo deadlift, bench press, and incline bench press. FHR and umbilical and uterine artery PI were measured before and after each exercise. In addition, all 60 participants were part of a prospective cohort study, completing an online survey in late pregnancy and a follow-up interview six weeks postpartum to assess exercise patterns, pregnancy experiences, and maternal and neonatal health outcomes. Results: Mean exercise intensity was 16.4 RPE and 89.4% MHRmax during running, and 16.0 RPE and 84.6% MHRmax during cycling. Mean FHR was 140.9 beats per minute (bpm) following running intervals and 148.9 bpm following cycling intervals. Six cases of prolonged fetal bradycardia (<110 bpm for ≥3 min) occurred during running, all resolving within eight min postexercise. In these cases, the athletes exercised at 17–18 RPE and 86.4%–92.6% of MHRmax. No prolonged bradycardia was observed during cycling. Exercise was terminated for three athletes during running and two during cycling due to prolonged fetal tachycardia (≥180 bpm for >4 min). During heavy-load resistance training, mean FHR remained within the normal range (110-160 bpm). Statistically significant increases were observed after sumo deadlifts (p=0.002) and incline bench press (p=0.008), with no significant change after bench press (p=0.122). Uterine artery PI decreased significantly following all exercises (p<0.01), whereas umbilical artery PI remained unchanged. One case of prolonged fetal bradycardia was observed after bench press, resolving shortly after three minutes. Additionally, one recreational athlete experienced symptoms consistent with vena cava syndrome during the supine exercise, however, FHR remained within the normal range and umbilical artery PI decreased slightly. Elite athletes exercised an average of 11.6 hours/week (SD 3.2) and recreational athletes 7.0 hours/week (SD 2.4) during pregnancy. Most participants resumed exercise within 6 weeks postpartum. Almost all pregnancies were planned, including six conceived through fertility treatment. The majority of women (76.7%) had spontaneous onset of labor and vaginal deliveries at term (36–42 weeks). Mean birthweight was 3487g (SD 519.4, range: 2600–4775g), with no cases of low birthweight (<2500g) and a lower rate of preterm birth (1.6%) than the national average (5.8%). Two elite athletes developed gestational diabetes mellitus and two developed hypertension during pregnancy, whereas none of the 50 recreational athletes reported pregnancy complications. Conclusion: The findings suggest that two acute bouts of high-intensity interval training, a heavy-load resistance protocol, and high-volume exercise are generally well tolerated by both the pregnant athlete and the fetus, and that the transient changes in FHR observed during training were not clinically meaningful. These results, alongside previous research, suggest that pregnant athletes may safely train at higher intensities, loads, and volumes than current conservative guidelines recommend, provided training is individualized and monitored. Based on this, future guidelines should differentiate between the general population and elite and recreational athletes to better reflect their physiological capacity.

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