In this episode, I sit down with exercise physiologist Dr Margie Davenport for a conversation that should change how we talk about exercise during pregnancy and the postpartum period. Margie chaired the 2019 Canadian Guideline for Physical Activity throughout Pregnancy, which became the basis for the World Health Organization’s 2020 recommendations. She also chaired the 2025 Canadian postpartum guideline and the upcoming International Olympic Committee consensus statement on athletes through pregnancy and postpartum. Her lab at the University of Alberta has done what previous researchers could not: directly measured fetal heart rate and blood flow during high-intensity intervals, heavy squat, bench, and deadlift sessions, peak exercise tests in twin pregnancies, and contact sport.
For decades, pregnant women have been told to stay below 140 beats per minute, avoid heavy lifting, skip HIIT, and pause everything after 12 weeks if there is any contact involved. Almost none of that is supported by the evidence we now have. In this conversation, Margie walks through what the data actually shows, why the public is still drowning in outdated advice, and why the bigger story is a shift from paternalistic prohibitions toward athlete-centred shared decision-making.
What we cover:
- Where the “stay below 140 bpm” rule came from in 1985, and why it should not have survived the last 40 years
- The size of the benefits we are actually talking about: roughly 40 percent fewer cases of preeclampsia and gestational diabetes, and around 67 percent fewer cases of depression during pregnancy
- What direct fetal monitoring during HIIT and heavy resistance training really shows, and why the “exercising muscles steal blood from the baby” idea is wrong
- A survey of nearly 700 women lifting above 80 percent of one-rep max in pregnancy, and the 51 percent reduction in complications among those who kept lifting heavy
- How 1980s baboon car-crash data still shapes recommendations on contact sport, and what the modern numbers look like
- The new postpartum picture: a 45 percent reduction in postpartum depression, why “wait six weeks” has no evidence behind it, and why breastfeeding does not raise injury risk
- Heat, hot tubs, scuba, twins, and the very few situations where the answer really is “don’t”
- The bigger paradigm shift, from blanket prohibitions toward shared decision-making between the athlete, her doctor, and her coach
This is a conversation I wish every pregnant woman, postpartum woman, and clinician had access to. Margie has built one of the most prolific labs in the world on this topic, and she is generous with what she knows. If you have ever been confused by conflicting advice, this should clear a lot of it up.
To connect with Dr Margie Davenport, visit exerciseandpregnancy.ca, follow her on Instagram at @DrMargieDavenport, or find her on LinkedIn and YouTube.
- Intro (00:00)
- Why Pregnancy Exercise Advice Feels So Confusing (01:15)
- The Most Damaging Myth About Exercise In Pregnancy (03:08)
- How Exercise Cuts Pregnancy Complications By 40% (05:05)
- Why Pregnant Women Were Excluded From Research (07:46)
- Can You Do High Intensity Workouts While Pregnant (12:49)
- How Exercise Lowers Preeclampsia And Diabetes Risk (16:43)
- How Much Exercise Is Safe During Pregnancy (27:03)
- Is Heavy Lifting Safe During Pregnancy (32:10)
- What You Should Never Do While Pregnant (40:41)
- Pelvic Floor Exercises Every Pregnant Woman Needs (47:41)
- How To Know If You’re Overexerting While Pregnant (56:12)
- Does Exercise Affect Fertility And Conception (1:00:42)
- Why The 140 BPM Myth Still Exists (1:04:52)
- How Exercise Improves Postpartum Mental Health And Sleep (1:09:28)
- The Truth About The 6 Week Postpartum Rule (1:11:32)
- Does Breastfeeding Increase Your Risk Of Injury (1:17:13)
- Why Pregnant Athletes Need Better Policy Support (1:19:56)
- What Future Pregnancy Exercise Research Will Reveal (1:24:50)
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More about Dr Margie Davenport
Margie Davenport, PhD is an exercise physiologist and Professor in the Faculty of Kinesiology, Sport, and Recreation at the University of Alberta, Canada. As the Christenson Professor in Active Healthy Living and Director of the Program for Pregnancy and Postpartum Health, Dr Davenport has spent more than two decades researching physical activity and sport participation throughout the reproductive years.
Her work is defined by a commitment to addressing the historical and systemic exclusion of pregnant and postpartum individuals from sport science research. Dr Davenport’s research spans the full spectrum of maternal health from high-risk clinical conditions where exercise is traditionally discouraged, to the general population seeking physical and mental well-being, to elite athletes returning to the world stage.
Dr Davenport chaired the 2019 Canadian Guideline for Physical Activity throughout Pregnancy, the 2025 Canadian Guideline for Physical Activity, Sedentary Behaviour, and Sleep throughout the First Year Postpartumand the upcoming 2026 International Olympic Committee Consensus Statement on Preconception, Pregnancy, and Postpartum in Athletes. These landmark documents, alongside the Get Active Questionnaires for Pregnancy andPostpartumprovide pregnant and postpartum women with evidence-based information to empower them to make decisions about physical activity and sport participation.
With over 200 published manuscripts, she collaborates with organizations including FIFA, the World Health Organization, International Olympic Committee, the Women’s Tennis Association and International Federation of Gynecology and Obstetrics to remove barriers to participation in exercise and sport.
