Fear of Falling: Understanding Pregnant Women's Changing Gaits
Besides the bulging belly, the "waddle"—the telltale sign of a shifted center of gravity—is a key distinguishing feature of pregnant women. For many, this feeling of being off-kilter translates to a fear of falling, thus deterring them from engaging in many forms of physical activity where the risk of falling is increased.
"A recent study that examined 4,000 pregnant women found that 27 percent of them fell during their pregnancy," said Danielle Symons Downs, associate professor of kinesiology and obstetrics and gynecology. "Changes in elevation are the primary source of falling accidents. So it's not surprising that many pregnant women decrease or avoid exercising altogether because they are worried about falling and harming their babies. However, research consistently shows that the health benefits of exercising while pregnant outweigh the risks of falling as long as the exercise is conducted in a safe fashion."
Danielle Symons Downs
To simultaneously investigate the psychological and biomechanical aspects associated with falling while pregnant, Downs, who specializes in psychological and behavioral aspects of physical activity, teamed up with colleague Jinger Gottschall, assistant professor of kinesiology with expertise in the biomechanical aspects of physical activity.
"The issue of falling while pregnant is one that requires an understanding of both women's attitudes toward falling and their physical and, perhaps unconscious, responses to uneven terrain," said Downs. "Our unique collaboration has allowed us to examine these issues with the ultimate goal of informing more specific recommendations for pregnant women regarding how to engage in healthy exercise while maintaining physical safety, particularly as pregnancy progresses to delivery."
In a recent study by Gottschall and Downs submitted to the Journal of Electromyography and Kinesiology, 13 pregnant women between 20 and 32 weeks gestation completed a standing trial and series of randomly assigned walking conditions in a laboratory protocol. Their goal was to determine whether and how pregnant women's gaits change as they transition between level and hill surfaces. Specifically, the researchers examined the participants' strides as they walked up a custom-built 2.4-meter ramp with a 15-degree incline, across a raised 4.8-meter plateau, and back down again. The team placed markers on the participants' feet, legs, hips, and backs and recorded their movements as they walked using a 3D camera system. The researchers also measured electromyography—or muscle activity—by attaching electrodes to the participants' legs.
"Most people alter their gait to avoid tripping when walking on uneven ground, but we found that pregnant women adopt an exaggerated gait strategy compared to non-pregnant adults," said Gottschall. "The women become more cautious during walking with their gait as they advance through pregnancy."
In another study, the researchers are examining pregnant women's attitudes regarding physical activity during pregnancy. They are using surveys to determine how frequently and how intensely women exercise at various points prior to pregnancy, during pregnancy, and after pregnancy. They also are investigating how fearful these women are of falling and whether they actually have fallen.
Knowing that pregnant women are generally fearful of falling, especially during later stages of pregnancy, and also knowing that women alter their gait in an exaggerated way in response to uneven terrain, Downs and Gottschall conclude that if pregnant women do not feel comfortable walking outside, a treadmill or a track are options, particularly as pregnancy progresses toward delivery.
"By following this recommendation, pregnant women can get the beneficial exercise they need while minimizing a possible fall," said Gottschall.