For years, the absence of robust research led to a cautious approach toward heavy resistance training during pregnancy. As more research is being done on the pregnant population the evidence is becoming clear that activity, including heavy weight lifting, does not increase risk to mom or baby, but rather it improves pregnancy, delivery, and postpartum outcomes.
A pivotal study by Revett et al. (2022) in the International Urogynecology Journal revealed that women who engaged in heavy resistance training (lifting more than 80% of their one-repetition maximum) experienced fewer pregnancy and delivery complications compared to those who reduced or ceased training. Pregnancy and delivery complications were listed as gestational hypertension (high blood pressure during pregnancy), preeclampsia (high blood pressure and protein in urine during pregnancy), unexplained vaginal bleeding, premature
labor, preterm delivery, placenta previa after 28 weeks, instrument assisted delivery (forceps and vacuum), and perineal tearing (grades 1, 2, and 3). Moreover, postpartum benefits for these women encompassed reduced instances of anxiety, depression, urinary and anal incontinence, dyspareunia, and diastasis recti. They also demonstrated a higher likelihood of returning to weightlifting postpartum.
Further reinforcing these findings, a 2024 study published in the British Journal of Sports Medicine by Moolyk et al. examined the effects of high-intensity resistance exercise (70-90% of 1RM) during pregnancy. The research confirmed that such training is safe and well-tolerated by both mother and fetus, challenging previous theoretical concerns about potential risks like elevated maternal blood pressure affecting fetal blood flow. The study emphasized the importance of evidence-based guidelines to alleviate unwarranted fears and encourage continued physical activity during pregnancy.
Complementing these studies, a comprehensive review by Duchette et al. (2024) in the International Journal of Women’s Health highlighted that resistance training during pregnancy can alleviate common symptoms such as fatigue, back pain, and poor mental health. Additionally, it aids in glucose control for gestational diabetes mellitus, reduces the risk of infant macrosomia, and enhances the likelihood of vaginal delivery. Importantly, the review found that resistance training increases uterine blood flow and poses no risk to fetal health and development.
These findings align with updated guidelines from leading health organizations. The American College of Obstetricians and Gynecologists (ACOG) now recommends that, in the absence of contraindications, pregnant individuals engage in regular physical activity, including strength training, to promote overall health and well-being.
This data supports that exercise is critical to maintaining a healthy pregnancy and facilitating a smooth postpartum return to activity, a philosophy we believe in and utilize within our treatments here at Mend. To learn more about maintaining or starting an exercise program during pregnancy, click here to schedule with one of our specialists in our Boulder or Lafayette locations today!
References:
1. Revett, C., Kimber, M.L., Forner, L., & Woodley, S.J. (2022). Impact of heavy resistance training on pregnancy and postpartum health outcomes. International Urogynecology Journal. https://doi.org/10.1007/ s00192-022-05366-z
- Moolyk, A.N., et al. (2024). Maternal and fetal responses to acute high- intensity resistance exercise during pregnancy. British Journal of Sports Medicine. https://doi.org/10.1136/bjsports-2024-108804(Medical Xpress)
- Duchette, C., et al. (2024). Benefits of Resistance Training During Pregnancy for Maternal and Fetal Health: A Brief Overview. International Journal of Women’s Health, 16, 1137–1147. https://doi.org/10.2147/ IJWH.S462591(PMC)
- American College of Obstetricians and Gynecologists. (2020). Physical Activity and Exercise During Pregnancy and the Postpartum Period: ACOG Committee Opinion, Number 804.