To break the monotony of my coronavirus routine, I recently clicked on an exercise app on my phone and found a strength class run by an ultramarathoner. The class started like any other — the instructor, one of the app’s most popular, encouraging hard work, heavy weights and no excuses with a smile. The only difference from previous classes was her belly bump.

Right up until she gave birth in March, she continued to lead her regular spinning and strength classes and also started a prenatal series.

Having gone through two pregnancies of my own, I was delighted. It was the first time I had seen a pregnant woman intensely exercising.

Plenty of athletes get pregnant. But we often don’t get an opportunity to witness them exercising in their second and third trimesters, even though the benefits of exercise during pregnancy are well documented. For instance, prenatal physical activity can lead to a lower incidence of gestational diabetes, preterm birth, hypertension and caesarean births, according to the American College of Obstetricians and Gynecologists (ACOG). Physical activity during pregnancy may also reduce body pain and postpartum recovery time and prevent depressive disorders postpartum.

In uncomplicated pregnancies, ACOG recommends in its latest guidance from April 2020 aerobic and strength-conditioning exercises throughout the prenatal period and postpartum, including 150 minutes of “moderate intensity aerobic activity” each week. Stationary cycling, resistance exercises (such as using weights), and walking are some of the physical activities ACOG suggests.

Newly pregnant women should be sure to have a thorough evaluation by a health-care provider to make sure there are no medical issues, such as preeclampsia or pregnancy-induced high blood pressure, that would prevent an expectant mother from safely exercising.

Women who engage in vigorous physical activity before pregnancy, such as the exercise app instructor, can continue while pregnant, ACOG says.

Yet, some doctors and their patients are cautious about this, fearing injury to the pregnant woman or her growing baby.

“My line . . . is whatever you did before pregnancy, you can continue to do and after it gets more difficult, listen to your body,” says Johnna Nynas, an OB-GYN at Sanford Health of Northern Minnesota.

Brittany Robles, an OB-GYN who is also a fitness instructor certified by the National Academy of Sports Medicine, says, “If you’ve been doing exercise before pregnancy and you’ve been a very active person, even weightlifting, you can pretty much continue whatever you were doing.” Robles — and ACOG — recommend that women be able to carry on a conversation while exercising to ensure they are not overexerting themselves, also known as the “talk test.”

Pregnant women should stop exercising if they experience any warning signs, such as vaginal bleeding, abdominal pain or dizziness, according to ACOG. “I usually tell patients — listen to your body. Your body is so good at nonverbal communication and will let you know when something is not right,” Robles says.

Exercise is even encouraged if a person was not active before pregnancy. “If someone has never exercised before, I always say start with walking. You can walk at a faster pace or try to beat your time and then once you’re feeling good, you can move on to something else,” Robles says.

ACOG recommends that pregnant women stay hydrated, wear loose fitting clothing and avoid high heat. Scuba diving, contact sports that increase risk of injury to the abdomen or activities with an increased risk of fall are also not advised, according to both ACOG and Vonne Jones, an OB-GYN at Total Women’s Care in Houston.

Even though exercise is beneficial to both mom and baby, approximately 60 percent of pregnant women surveyed in a 2015 study published in the American Journal of Preventive Medicine reported they did not engage in any physical activity.

There is still fear surrounding physical activity and pregnancy. “There is a lot of misinformation out there saying that once you get pregnant you have to stop” exercising, Jones says. The false idea that “exercise causes miscarriage — I hear that a lot.”

Experts say pregnant women are more likely to exercise — and stick to it — during pregnancy if given clear direction from their health-care provider, but not all women get that direction.

Some 50 percent of pregnant women reported that they did not receive any counseling or received inadequate counseling on exercise during the prenatal period, according to a survey conducted by the University of South Carolina School of Medicine on 224 postpartum women.

When I was pregnant with my first daughter, I recall my obstetrician telling me it was good to exercise but to be careful about lifting weights. When I asked what would be too heavy, she responded that she had never done any weightlifting and did not provide any guidance. I had lifted for years, but after our conversation, I was confused and feared I might harm my baby, so I started to exercise less. I gained almost 50 pounds, was in physical pain from that and needed two years to fully recover postpartum.

Inadequate counseling from medical providers stems from many different factors, such as the lack of time a provider is allotted with a patient or a lack of training about exercise and pregnancy.

“It’s self-education,” Jones says. “It is going in and reading committee opinions, practice bulletins and coming up with your own set of guidelines for exercising.”

Women who do not receive adequate instruction often turn to non-health-care professionals, such as family and friends or the Internet, for guidance.

These resources can be unreliable and lead to misinformation.

“Unless those people are board-certified OB-GYNs or other health-care professionals with their various degrees of expertise, you’re going to get a mixed bag of information,” Nynas says.

As a result, pregnant women are often not educated on all the benefits of physical activity or given clarity in regard to which exercises are safe for their body.

Additional research is needed on exercise and pregnancy.

“One thing that is most lacking is how we teach patients about this,” says Meredith Birsner, a maternal-fetal medicine specialist at St. Luke’s University Health Network in Pennsylvania and lead author of the most recent ACOG opinion on exercise and pregnancy. “Providers need to understand how to get through to our patients and be able to sensitively and compassionately advise them on how to exercise.”

When I became pregnant for the second time last year, I followed my midwife’s advice and listened to my body. I continued the physical activity I did before getting pregnant: I ran, did yoga, biked and lifted weights. As my pregnancy progressed, I shortened my rides, stretched more and rested when I needed, but I exercised until the day I went into labor. I had more mobility throughout my pregnancy, an easier labor and a faster recovery.

“With the accumulation of newer evidence suggesting again the overwhelming benefits of exercise in pregnancy I think that is one of the messages that is important to get out,” Birsner says.

As when you are not pregnant, exercise and strength are important for physical and mental health. Fortunately, more doctors and pregnant women are embracing that notion.