Precision Prescription of Physical Activity during Pregnancy

BY Joshua R. Sparks, PhD

Pregnancy is a unique “teachable moment” during a woman’s life where improvements to lifestyle behaviors, including diet and physical activity, not only serve to enhance their health, but also the health of their child. Traditionally, physical activity declines during pregnancy due to psychological reasons, such as desire to engage in physical activity, and physiological reasons, including fatigue due to childbearing. Yet, there are several health benefits to maintaining or increasing physical activity during pregnancy. These include reducing the risk for excess gestational weight gain (GWG), development of gestational diabetes mellitus, birth complications and incidence of cesarean section, and birthing a baby large for gestational age.

Despite these potent health benefits, women fail to meet physical activity recommendations during pregnancy. Although the recommendations are simplistic in nature, 150 minutes of moderate-intensity physical activity each week, the blanket prescription is vague and doesn’t educate women on how to be physically active during pregnancy. They also do not clearly address the individual-level factors that determine physical activity during pregnancy, including fear of complications due to excess physical activity or offering proper support for engagement.

In over 400 women who were currently pregnant or recently pregnant within the past 2 years, our online survey study captured 1) physical activity habits in pregnancy, 2) willingness to engage in recommended physical activity guidelines according to the basics of the FITT principle: frequency (1-7 days per week), intensity (moderate), time (150 minutes per week), and type (aerobic), and 3) barriers and facilitators of physical activity engagement. Unexpectedly, most women reported engaging in some form of cardio-based physical activity, but excitingly were willing to participate in 2-5 days of structured physical activity to meet the physical activity recommendations. However, they reported feeling too tired or uncomfortable and childcare needs as primary barriers, while stating that flexibility in timing and location of physical activity and having a prescribed physical activity regimen would be beneficial to combat these barriers. Other reported barriers and facilitators to physical activity engagement during pregnancy included ensuring proper energy intake, motivation, and support from other pregnant women.

Implications for Public Health Practice: There is a continual shift to empower and enable women to feel comfortable and safe with engaging in behavioral and lifestyle changes during pregnancy. The United States Preventive Services Task Force recently recommended that providers offer pregnant individuals effective behavioral counseling, including physical activity. Rapid advancement in maternal healthcare has allowed for pregnancy and birth outcomes to be the focal point of prenatal care. To adequately prescribe physical activity during pregnancy, trained providers need to be incorporated, such as exercise specialists, which necessitates policy-level change to ensure financial compensation for services delivered. Additionally, if clinicians can individually tailor physical activity prescriptions based on factors such as current fitness level and individual time allocation, they may enhance continual engagement in physical activity by designing the program with the patient at the center. Lastly, with the advent of technologies (i.e., pedometers and accelerometers) and mobile applications (e.g., MyFitnessPal), real-time physical activity feedback may be provided to the pregnant woman, while adaptive feedback may be provided through clinician engagement to individually enhance opportunities to be physical active. Collectively, leveraging the expertise of health professionals, including exercise specialists, in conjunction with self-monitoring tools and additional real-time and adaptive feedback to pregnant individuals, allows for greater personalized prescription of physical activity. This approach also accounts for reported barriers, such as time and location to allow for physical activity engagement of pregnant individuals.