May 23, 2000 -- The unflattering "waddle" often associated with a pregnant woman's gait appears to be no more than a myth, according to new research. Although investigators have found that women walk the same way before and during pregnancy, the changes in their body mass and distribution do leave them at increased risk for low back, hip, and calf pain due to overuse.
"With big changes in body weight and distribution, regular exercise prevents joint wear and tear, especially in the pelvis, hips, and ankles," says study author Theresa Foti, PhD, a kinesiologist at Shriners Hospital for Children in Greenville, S.C.
Foti explored gait patterns in 15 women between the ages of 25 and 38 during their final weeks of pregnancy. Participants were videotaped walking across a room, and their strides were compared using motion analysis software. The process was repeated a year later for all but two participants, who were tested prior to pregnancy.
Overall, gait patterns were remarkably unchanged during pregnancy. There was no evidence of a waddling gait, but there were significant increases in hip and ankle forces, indicating that muscles and joints compensate for changes in body mass. These adjustments allow for a normal stride but place muscles and joints at high risk for overuse injuries, particularly among inactive women. The research was published in the current issue of The Journal of Bone and Joint Surgery.
Fortunately, exercise helps prevent overuse injuries and has many other benefits as well. "Most physicians now recommend mild to moderate exercise during pregnancy, even for women who didn't exercise previously," says Michael Lindsey, MD, director of maternal/fetal medicine at Emory University Hospital and associate professor of obstetrics/gynecology at Emory University School of Medicine, both in Atlanta.
Regular exercise is associated with shorter labor and faster postpartum recovery, although safety remains an important consideration. "Maintaining a basic level of fitness is fine, but pregnancy is not the time for vigorous exercise or weight loss," adds Lindsey. "After the first trimester, I also advise against sit-ups and weight training, particularly in women at risk for preterm labor."