Professional Exercise Recommendations for Healthy Women Who Are Pregnant: A Systematic Review

Abstract

Background: Exercise in pregnancy favorably affects maternal and fetal outcomes, yet only 50% of women receive exercise guidance during prenatal care and 15% are told to stop exercising. Reasons for clinician reluctance to recommend exercise include safety concerns and ambiguity of recommendations. To better inform clinicians, this systematic review assembled a consensus exercise prescription (ExRx) for healthy pregnant women framed by the Frequency, Intensity, Time, and Type (FITT) principle. Methods: In April 2021, PubMed, Scopus, SPORTDiscus, Cumulative Index of Nursing and Allied Health Literature (CINAHL), and Cochrane databases were searched. Reports were eligible if: (1) targeted healthy pregnant women, (2) framed the ExRx by the FITT, and (3) published by a professional society from 2000 to 2021 in English. The Appraisal of Guidelines for Research and Evaluation II tool assessed risk of bias. Results: Twelve reports of poor to good quality were included. Nine societies conducted systematic reviews, but only three provided a detailed, transparent description of the review conducted. Although the FITT varied, the most common was most days of the week, moderate intensity, 30 minutes/session to accumulate 150 minutes/week, and aerobic, resistance, and flexibility exercise with three societies advising neuromotor exercise. All professional societies specified activities to avoid and eight societies included contraindications to exercise. Conclusions: This systematic review produced a consensus ExRx for healthy pregnant women to better inform clinicians about advising their patients to exercise during pregnancy. Future research is needed to determine the upper limits of exercise while pregnant and provide better informed guidance relating to safety concerns for women who are pregnant.

A narrative review of exercise dose during pregnancy

“…As women advance into late gestation, intense exercise should be monitored as maximal ventilation may be reduced (Knuttgen & Emerson, 1974). Although further research is needed related to extreme intensities (Beetham et al, 2019), pregnant exercisers should feel comfortable exercising up to 90% maximum heart rate, RPE of 12-14 on a 6-20 Borg RPE chart, and to the point where talking becomes difficult (Rudin et al, 2021).…”

“…The guidelines from the World Health Organization, the International Olympic Committee, and Canadian and American councils, all recommend a similar exercise dose (American College of Obstetricians and Gynecologists, 2020; Bø et al, 2018; Evenson et al, 2019; Rudin et al, 2021; Wolfe, Hall, et al, 1989) which has been justified as safe by past research groups. Yet, there is evidence of a dose–response relationship to gestational health outcomes (Davenport, Sobierajski, et al, 2018; Ehrlich et al, 2016; Ruchat et al, 2018; Wang et al, 2017), suggesting that exceeding the recommended dose may be beneficial.…”

“…The current recommendations from the ACOG align with those from the American College of Sports Medicine, which are 150 min of moderate intensity every week of pregnancy (American College of Obstetricians and Gynecologists, 2020; Birsner & Gyamfi‐Bannerman, 2015). This cautionary recommendation is probably due to the lack of agreement on the “upper” limit for safe exercise in pregnancy (Rudin et al, 2021; Wieloch et al, 2022), despite numerous studies showing no adverse effects of high(er) intensity exercise on pregnancy or birth complications (Juhl et al, 2008; Juhl et al, 2010; Kardel, 2005; Kardel & Kase, 1998; Lokey et al, 1991; Penttinen & Erkkola, 2007; Zeanah & Schlosser, 1993). In the words of Raul Artal, “Pregnancy should not be a state of confinement and cardiovascular and muscular fitness can be reasonably maintained.…”

“…Prenatal exercise recommendations from ACOG and other professional organizations (Rudin et al, 2021) suggest a training frequency of at least 3–4 times per week, with a maximum of 7 days per week (American College of Obstetricians and Gynecologists, 2020). Studies have implemented frequencies within the guidelines, and there is a lack of evidence concerning lower‐frequency prenatal exercise (Table 1).…”

“…Prenatal exercise recommendations suggest an exercise duration per session of 30–60 min (American College of Obstetricians and Gynecologists, 2020; Rudin et al, 2021). Studies have generally focused on bouts lasting longer than 30 min, with a lack of evidence regarding low‐duration prenatal exercise (Table 1).…”