Previous research clearly indicates that exercise training decreases during pregnancy, even among the fittest of women. Despite this, women are typically able to resume their prepregnancy exercise routines soon after delivery, and in some instances, their postpartum performances are better than previously experienced. While anecdotal reports are common, there does not appear to be significant research data to explain this phenomenon. In this review, we explore possible physiologic explanations for heightened postpartum exercise performance, such as pregnancy related changes in aerobic fitness, lactate threshold, flexibility, and musculoskeletal fitness. At this time, limited data do not appear to support an ergogenic role for these variables. Another consideration is a positive change in a woman’s psyche or perceptions toward her athletic abilities as a result of her pregnancy and delivery. While this concept is theoretically possible and may have scientific merit, data are sparse. What is clear is that an increasing number of women are maintaining their physical activity and exercise routines during pregnancy, with many able to return to competition soon after delivery. Well-designed studies are needed to further explore the relationships among physiologic and psychological variables and postpartum exercise performance. Ideally, these studies should be prospective (studying women prepregnancy through the postpartum period) and include diverse samples of women with regard to activity type and fitness level.