Why Resistance Training During Pregnancy Benefits Both You and Your Baby

If you're pregnant and lifting weights, someone has probably told you to stop. Despite decades of research showing that resistance training is safe during pregnancy, outdated fears persist. A 2024 review in the International Journal of Women's Health makes it clear: not only is strength training safe for pregnant women, it's one of the most beneficial things you can do for both maternal and fetal health.

Yet only 11% of pregnant women in the United States do any resistance training, and many healthcare providers still don't recommend it.

What the Research Shows

Resistance training during pregnancy helps with nearly every common complaint: fatigue, back pain, poor mental health, excessive weight gain, and gestational diabetes. It improves labor outcomes, reduces the risk of cesarean delivery, and decreases the likelihood of having a macrosomic (overly large) baby—which carries its own set of risks.

For the baby, maternal strength training is associated with improved cognitive function in childhood, better metabolic health, and reduced risk of obesity later in life.

Gestational Diabetes

Women with gestational diabetes who performed resistance training needed less insulin and achieved better blood glucose control than those who didn't exercise. Multiple studies found that moderate-intensity resistance exercise (using resistance bands or light weights 2-3 times per week) reduced fasting and postprandial blood glucose, insulin requirements, and gestational weight gain.

In one study, resistance training delayed the need for insulin therapy entirely in some women who would have otherwise required it.

Back Pain and Fatigue

About 76% of pregnant women experience back pain, often severe enough to interfere with daily activities and sleep. Resistance training—particularly exercises targeting core strength—improves posture, reduces lumbar lordosis, and alleviates joint discomfort in ways aerobic exercise alone cannot.

Women who strength trained during pregnancy maintained their energy levels throughout pregnancy, while those who didn't experienced significant declines in vitality and increases in fatigue.

Mental Health

Resistance training improves self-esteem, body image, and sense of control during pregnancy—all protective factors against anxiety and depression. Combined with regular physical activity, strength training has been shown to decrease both the incidence and severity of depression during pregnancy.

Labor and Delivery

While results are mixed, several studies found that women who did resistance training had shorter first-stage labor, lower rates of operative delivery (forceps, vacuum, or cesarean), and fewer delivery complications. At minimum, strength training doesn't increase labor time or cesarean risk—and may actively improve outcomes.

Fetal Safety

One of the biggest fears is that exercise will reduce blood flow to the fetus. Research shows the opposite: resistance training increases uterine blood flow post-exercise, improves placental growth, and reduces oxidative stress. Changes in fetal heart rate during maternal strength training indicate increased fetal wakefulness and activity, not distress.

Infants born to mothers who strength trained are more alert, better at self-soothing, less agitated, and show better cognitive development in childhood than those born to sedentary mothers.

Macrosomia and Long-Term Health

High birth weight (macrosomia) increases the risk of birth injuries, cesarean delivery, neonatal intensive care needs, and childhood obesity, diabetes, and cardiovascular disease. Multiple studies found that resistance training during pregnancy reduced the incidence of macrosomia—particularly in women with gestational diabetes.

Safety Considerations

Resistance training during pregnancy is safe when done correctly. Women should avoid:

• Supine positions (lying flat on back) for extended periods, especially in later pregnancy

• The Valsalva maneuver (holding breath during exertion)

• Exercises that rely heavily on balance (as center of gravity shifts)

• Ballistic movements or risk of abdominal trauma

• Overheating (stay hydrated, wear appropriate clothing)

Light to moderate weights, resistance bands, and bodyweight exercises are all effective. The goal isn't to maximize strength gains—it's to maintain functional fitness and prevent significant losses in strength and mobility.

The Bottom Line

Resistance training during pregnancy helps control gestational diabetes, manages weight gain, reduces back pain and fatigue, improves mental health, and may improve labor outcomes. For the baby, it supports healthy birth weight, cognitive development, and long-term metabolic health.

With appropriate modifications and attention to safety, strength training represents one of the most evidence-based interventions available to improve pregnancy outcomes. It's time for healthcare providers to start recommending it.

References: Duchette, C., Perera, M., Arnett, S., White, E., Belcher, E., & Tinius, R. (2024). Benefits of Resistance Training During Pregnancy for Maternal and Fetal Health: A Brief Overview. International Journal of Women's Health, 16, 1137-1147.