The American Congress of Obstetricians and Gynecologists recommends that pregnant women use the rate of perceived exertion (RPE) scale when determining intensity. While pregnant a woman should maintain a level of exercise she considers to be fairly light to somewhat hard (RPE of 11-13 on the Borg 6-20 scale). They also state that, “For women who do not have any additional risk factors for adverse maternal or perinatal outcome, the following recommendations may be made. During pregnancy, women can continue to exercise and derive health benefits even from mild-to-moderate exercise routines. Regular exercise (at least three times per week) is preferable to intermittent activity. Prolonged periods of motionless standing should also be avoided. If you have been sedentary prior to conception, it is important to begin any exercise program gradually and progress slowly.”

Further, any type of exercise involving the potential for even mild abdominal trauma should be avoided. Pregnancy requires an additional 300 kcals per day in order to maintain metabolic homeostasis. Thus, women who exercise during pregnancy should be particularly careful to ensure all nutrition needs are being met. Pregnant women who exercise in the first trimester should augment heat dissipation by ensuring adequate hydration, appropriate clothing, and optimal environmental surroundings during exercise. Many of the physiologic and morphologic changes of pregnancy persist for four to six weeks postpartum. Thus, pre-pregnancy exercise routines should be resumed gradually based on a woman's physical capability.