Background. Physical activity is associated with reduced mortality and morbidity. Cardiac rehabilitation (CR) is an effective intervention for patients with cardiovascular disease (CVD). Unfortunately, women are less likely to engage in, or sustain, regular physical activity. Objectives were to (1) describe women’s guidelines-based levels of physical activity during and after CR and (2) determine the physical activity trajectories of women from entry to CR to one year after CR.Methods and Results. A prospective, longitudinal study of 203 women with CVD enrolled in a 6-month CR program. Physical activity was measured using the Godin Leisure Time Exercise Questionnaire (LSI), focusing on moderate-strenuous activity. Data were analyzed using latent class growth analysis (LCGA) and logistic regression. Mean scores on the LSI showed women to be “active” at all follow-up points. LCGA revealed a two-class model, respectively, called “inactive relapsers” and “moderately active relapsers.” Predictors of the “moderately active relapsers” class were employment status and diagnosis of myocardial infarction.Conclusions. Women achieved the recommended physical activity levels by the end of CR and sustained them until one year after CR. LCGA allowed us to determine the class trajectories associated with moderate-strenuous activity and, from these, to identify implications for targeted intervention.