This is a guest post by Jennifer Huberty
The positive health benefits of physical activity participation during pregnancy are well known. The American College of Obstetricians and Gynecologists recommends pregnant women achieve at least 150 minutes per week of moderate-intensity aerobic activity, such as brisk walking, during and after their pregnancy while avoiding activities such as contact sports and supine position activities after 20-weeks gestation.
Some women increase their physical activity immediately upon finding out they are pregnant or after morning sickness has passed. But most women don’t achieve the recommendations for physical activity and are completely inactive by the third trimester.
Pregnancy is often thought of as the opportune time to improve health behaviors. Because a baby is developing inside a woman’s body, she may be more motivated to make better decisions about her health. Pregnant women report wanting consistent information about how to safely engage in physical activity while pregnant, and they say such information would help them be more active.
In the study, eighty-five women were randomized to one of four groups in which they received texts during the entire length of their pregnancy.
Mobile phones have become a popular way to deliver health information and health behavior programs to a wide variety of populations. Over 90% of women in the United States own a mobile phone, with 80% using text messaging. Text4baby (T4b) is a free, nationwide, mobile health information service that delivers health-related texts to women during pregnancy and the first year postpartum.
We partnered with T4b to determine if physical-activity-based texts delivered to pregnant women would improve their physical activity levels. Our findings are published in the June 2017 issue of Translational Behavioral Medicine.
In the study, eighty-five women were randomized to one of four groups in which they received texts during the entire length of their pregnancy. These included
- Standard: three T4b texts (standard T4b content) per week (M,W,F) at noon;
- Plus one: two physical activity and one T4b texts per week (M,W,F) at noon;
- Plus six: six physical activity and one T4b texts per week (Su-Sa) at noon; and
- Plus six choice: six physical activity and one T4b texts per week (Su-Sa) at a time of choice.
Regardless of frequency or time of delivery, there were no increases in physical activity as a result of the text intervention. Across all groups, the plus six group had greater decreases in activity and greater increases in sedentary time. This was also true for sedentary time in the plus six choice group.
Our findings are not surprising as there are few studies that have been able to increase physical activity in pregnant women. Despite the lack of effects in our study, the information contributes to what we know about mobile health interventions and the use of texts to deliver health behavior programs to pregnant women. Pregnant women should not receive daily physical-activity-related texts.
Regardless of frequency or time of delivery, there were no increases in physical activity as a result of the text intervention.
Texts that provide quality information to improve knowledge (i.e., education) and support (i.e., non-contingent praise and motivators) and that rely on antecedent strategies may actually be aversive or inhibit women from becoming physically active. This could be due to habituations (i.e., diminishing response with repeated stimulus).
It is important to note that the physical activity patterns across all groups were consistent and illustrates a significant problem. Pregnant women have to overcome non-modifiable barriers to physical activity such as significant physical and physiological symptoms that occur during pregnancy (e.g., nausea, fatigue, weight gain, swelling, back and pelvic pain) and are often compounded by common modifiable barriers to physical activity (i.e., time, motivation, enjoyment) reported in both the general population and pregnant women.
Perhaps efforts related to targeting reduction in sitting or sedentary behavior in pregnant women may be more achievable. Increasing light intensity activity may also be more realistic in terms of what a pregnant woman’s barriers are to being active, especially in the third trimester. Because our findings suggest education alone delivered via text is not enough to increase physical activity, there is a need for more work in this area.
Jennifer Huberty, PhD, is an associate professor at Arizona State University in the School of Nutrition and Health Promotion, Exercise and Wellness program. Her research interests include physical activity adherence and lifestyle behavior change in women as well as the use of complementary approaches to improve health. She has implemented interventions using the Internet and text messages to improve mental and physical health in women (i.e., stillbirth mothers, pregnant women, cancer patients), and she works closely with industry partners such as Udaya.com and Text4Baby.