When I was in my first trimester with my first child, my husband ran the Leadville 100 ultra-marathon. While he was lost in the woods (literally speaking), I passed the time trail running while pregnant—at probably an altitude of 11,000 feet. I mentioned this to Jake and he went kind of nuts—“Was the baby even getting oxygen? That was not safe!” he said angrily.
To ward off future heated discussions of this ilk about my running while pregnant, we talked with my doctor who set parameters so that Jake and I both felt like running while pregnant was good for me and the baby. Those parameters were—if you’re a runner, it’s totally cool—no, it’s actually awesome—to keep running while pregnant. But, be smart and listen to your body.
In fact, in an unofficial poll of mother runners, moms who ran while pregnant stated many benefits:
- More energy
- Easier and quicker delivery
- Increased feelings of ownership of their bodies
- Increased sense of normalcy throughout pregnancy
- The knowledge that we can do hard things
- A decrease in morning sickness
- Heightened mental and physical endurance
- Learned importance of breath
- Healthier pregnancy
- Quicker postpartum recovery
Yet, there are a lot of misconceptions about running while pregnant. That’s because little was known about the effects even just 25 years ago.
Is it safe to run while pregnant?
In 1985, guidelines by the American College of Obstetricians and Gynecologists (ACOG) recommended pregnant women avoid high impact exercise, activities raising the maternal heart rate to exceed 140 beats per minute, physical activity longer than 15 minutes, and physical activity allowing the maternal core body temperature to exceed 100.4° F.
However, in 1994 the ACOG removed all restrictions on maternal exercise. Then, in 2002, it recommended that expectant women exercise for 30 minutes on most or all days of the week. Finally, in 2020, the ACOG outlined the various benefits of exercise for pregnant women.
There is a theoretical concern of a heightened possibility of joint-related injuries in pregnancy due to the hormone relaxin. However, research has not shown an increase in exercise-related injuries, and in fact, exercise has been shown to decrease the rates of musculoskeletal complaints during pregnancy.
What are the health benefits of running while pregnant?
There are numerous studies that reveal the health benefits of running while pregnant for expectant women.
For example, running while pregnant has been shown to improve or maintain physical fitness, help with weight management, reduce the risk of gestational diabetes, and enhance physical well-being.
Exercise has also been found to decrease the incidence of urinary incontinence, pre-eclampsia, lower back pain and the occurrence of Caesarean section. Also, pregnant women who exercise regularly during pregnancy benefit from increased energy and improved sleep.
There is also a huge component of self-esteem for women who run throughout their pregnancies. Exercise is good for the mood in general and it can help with a changing body and moodiness from hormonal fluctuations.
Can running while pregnant hurt the baby?
Running while pregnant cannot hurt your baby. Your body will tell you long before there is a real risk of limited oxygen or over-heating, for example, says Laura Norris, The Mother Runners head running coach.
Instead, research shows numerous benefits to the baby of mothers who ran while pregnant. A 2011 study showed an improvement in fetal development including more lean muscle mass, increased attentiveness, heightened discipline, and more neurodevelopmentally advanced.
Another study reported an increase in lean body mass in infants of mothers who exercised as well as seeing improved stress tolerance in these babies. The improved stress tolerance is of particular importance as “it relates to labor and delivery and the infants’ ability to handle both while maintaining reassuring heart tones,” note the researchers. Another study, performed with rats and not people, found that the babies of exercising mothers had improved memory.
Can running cause a miscarriage?
No. High-level exercise and running cannot cause a miscarriage. Research has shown that miscarriage cannot be prevented, and thus cannot be caused, according to Acadia Gantz, an ultra runner, run coach, and midwife based in Maine who has conducted research into pregnant high-level athletes, shares key insights into the benefits running has for babies and their mothers.
Can you start running during pregnancy?
The current recommendation for pregnant women is to continue the physical activity they practiced before they were pregnant. However, for some women, Acadia says it is okay for women to increase their fitness during pregnancy. “Doing this would be very individual and depend on base fitness at the beginning of pregnancy, fatigue/nausea, etc. during pregnancy and being realistic with goals throughout pregnancy and postpartum,” she explained.
When should a pregnant woman stop running?
A pregnant woman should stop running due to a medical concern and a recommendation by her doctor, or if running while pregnant feels uncomfortable. Many women have run up until the day they delivered (myself and Coach Laura included). However, for other women, it is just too uncomfortable. These women find other exercises that benefit their and the baby’s health but are less taxing on the body.
Is it OK to run long distances while pregnant?
Yes. Limitations on the duration of exercise were thrown out by ACOG. Instead, a minimum of 30 minutes per day is recommended.
Can I run a race while pregnant?
Yes! In fact, many pregnant runners, Laura included, do. I personally know many mother runners who ran marathons while pregnant. But running during pregnancy is not a time to try to set a personal record. Running a race should be something done for the pure joy of the experience, not for setting PRs.
The largest study ever completed on pregnant runners supports that running while pregnant is safe, including running distances up to a marathon.
Expert tips to help you keep running while pregnant
Talk to your doctor.
Every pregnancy is different. You may have complications or feel different than other Mother Runners. Whatever you do, make sure you tell your doctor that you’re continuing to run so that they can monitor how that’s going for you and the baby. Also, ask them to set guidelines like mine did—sharing your running history so they know what your body is used to doing.
Listen to your body.
If something doesn’t feel good or feels strange. Stop doing it. And, then share with your doctor what’s going on. Mother Runners advise not to push yourself hard. This is not a time to do speedwork and long runs. (Plus there is an increased risk of injury because of the relaxin hormone that’s pumping through your body getting it ready for birth—link). The comfort zone is the place to be when growing a human. Keep it easy. You’ll get it back.
Master the art of peeing outside (or find bathrooms).
I cannot tell you how many times I would have to pee (or at least felt like I had to pee) on a 4-mile run. I got really good at pretending like I was tying my shoe but instead was…well, you get the picture. Humility goes out of the door in the name of comfort. If this isn’t something you want to do, plan to run near public bathrooms.
Get a maternity support belt.
When the extra weight in my tummy got uncomfortable, I invested in the Gabriella Maternity Light Support Belt. Another fantastic one which a lot of professional runners use is ReCORE’s Fitsplint. A belt worked wonders in taking the pressure off so I could still log slow miles throughout my pregnancies. Also, this is common sense—but make sure you have good supportive shoes.
Manage morning sickness.
If you’re dealing with morning sickness and still trying to run—take heart. Our Mother Runners said sipping Gatorade on their runs helped calm their queasy stomachs. Dr. Cole Hosenfeld of Apple Healthcare recommends dropping your mileage by 10 percent to see if your symptoms ease.
Eat right and drink often.
Yes, you are eating for two, but you only need to eat about 350-450 more calories a day in your second and third trimesters. If you stick to that, says nutritionist Betsy Johnson, you’ll snap back faster after baby. Betsy recommends eating a mid-morning and late-afternoon snack. She says every meal should include healthy fats, carbs, and protein. Also, be sure to take your prenatal vitamins. (Here’s the latest review of the prenatals on the market). And, hydration is key! Your body needs water to produce amniotic fluid, extra blood volume, new tissue, supply nutrients, help indigestion, and flush out your wastes and toxins. Drink water all day long.
Find slower running buddies.
If you’re keeping your heart rate at 140 or below (or at a conversational pace), you may not be able to run with the same friends you ran before you became pregnant. Find people who will run at an easier pace. Or, if you are running with the same people, run with them on their easy days and let them know your limits. Speak up if the pace gets too fast.
Your body is working overtime growing a human and chances are your sleep is interrupted by discomfort and having to pee several times a night. Heed those heavy eyes and try to lay down whenever you have the opportunity to rest.
Raid your partner’s closet.
This is kind of genius—if you don’t want to spend a lot of money on maternity running clothes, consider raiding your partner’s closet for workout shirts you can wear while your tummy is housing a human.
Your body is freaking amazing. It’s built to run and it’s built to have babies. It’s going to be changing and doing what it needs to bring a human into the world. Don’t stress about gaining weight or missing runs. It’s adapting to this major change and it will adapt again after you have your precious baby.