Women with uncomplicated pregnancies can continue to light exercise during pregnancy if they had previously been followed to exercise prior to becoming pregnant. Studies indicate that well-conditioned women who maintain an antepartum exercise program consisting of aerobics or running have improved pregnancy outcomes in terms of shorter active labors, fewer cesarean section deliveries, less meconium-stained amniotic fluid, and less fetal distress in labor. On average, women who run regularly during pregnancy have babies that weigh 310 g less than women who do not exercise during pregnancy. Even though birth weight is reduced in exercising pregnant women, there is not an increased incidence of intrauterine growth retardation. The American College of Obstetricians and Gynecologists recommends that women avoid exercising while in the supine(Lying face upward) position to avoid a decrease in venous return to the heart, which results in decreased cardiac output. In addition, women should modify their exercise based on symptoms. There is not set pulse above which exercise is to be avoided; rather, women should decrease exercise intensity when experiencing symptoms of fatigue. Non–weight-bearing exercises will minimize the risk of injury. Since the physiologic changes associated with pregnancy will persist from 4 to 6 weeks following delivery, women should not resume the intensity of prepregnancy exercise regimens immediately following delivery.
