Pregnancy & postpartum
Is it safe to exercise on your back while pregnant?
Pregnancy Rules, Revisited: Episode 3
"Don't lie on your back after the first trimester." If you've heard some version of this, you've probably also wondered what that means for bench press, glute bridges, dead bugs, and half of your favorite yoga flow.
Where the rule came from
As your pregnancy progresses, your growing uterus can press on the inferior vena cava, a large vein that carries blood back to your heart, when you lie flat on your back. The concern is that this can reduce blood flow, including to the placenta. For some women, it leads to dizziness, lightheadedness, nausea, or feeling generally unwell, usually after several minutes on their back. That's a real and important response, and it's where the rule comes from.
What the research says
A 2019 systematic review led by Dr. Michelle Mottola looked at seven studies on exercise in the supine position during pregnancy. Exercise programs that included supine work weren't associated with low birth weight compared with no exercise, and the observational studies reported no maternal adverse events. A few lab studies did see short-term changes in baby's heart rate patterns and uterine blood flow during a single bout of exercise on the back, and overall the researchers concluded there isn't enough evidence yet to say whether supine exercise is safe or unsafe. In other words, the research doesn't support a blanket ban, and it also tells us to pay attention.
What the guidelines say
The 2019 Canadian guideline recommends that if you feel lightheaded, nauseous, or unwell when exercising flat on your back, you should modify your position. That puts the focus on how your body responds, rather than avoiding the floor entirely.
Easy ways to modify
If lying flat doesn't feel great, try these swaps:
- Use an incline bench or a wedge, or stack pillows under your upper back
- Switch to side-lying versions of core and hip exercises
- Keep supine sets short and move between positions
- Try standing, seated, or all-fours versions of the same movement
The takeaway
Exercising on your back isn't automatically off the table. Short bouts are generally fine if you feel good, and changing position is the move if you don't. As always, your training through pregnancy should be discussed with your provider based on your individual needs and goals.
And if you want help adapting your favorite exercises as your pregnancy progresses, I'd love to help. Reach out through the interest form or DM me ALIGNED on Instagram.
Research referenced
- Mottola et al., 2019. Is supine exercise associated with adverse maternal and fetal outcomes? A systematic review. British Journal of Sports Medicine. PMID 30337348
- Mottola et al., 2019 Canadian Guideline for Physical Activity Throughout Pregnancy. Read the guideline (PDF)
This post is general education, not medical advice. It isn’t a substitute for an evaluation by a qualified healthcare provider.