AIM: This paper reports on an interview study exploring the self-regulation process in women and men, 5 months after a first-time myocardial infarction. BACKGROUND: Somatic, psychological and social factors affect readjustment after a first-time myocardial infarction, and studies have demonstrated substantial rates of depression in patients after myocardial infarction Women report poorer mental health and physical condition than do men. Reconstruction of the self begins when disease poses novel problems and is more likely to occur in cases of long-lasting and disruptive illnesses. Experiencing myocardial infarction is likely to alter a person's mental representation of self. However, the self-regulation process following first-time myocardial infarction is not yet fully understood. METHOD: Twenty-one people (11 women, 10 men) were interviewed 5 months after first-time myocardial infarction. The grounded theory method provided the strategies for data collection and analysis. FINDINGS: Interviewees' definition of themselves as active was threatened by fatigue and other health problems that kept them from taking part in activities as they had done before the heart attack. Although reorienting the active self was central to the process of recovery from myocardial infarction, reorienting was restricted by illness perception and coping. CONCLUSION: Participants had not established a stable health condition 5 months after first-time myocardial infarction. They mainly preferred to moderate rather than radically change their daily life activities. They needed more knowledge and support. Nurses can help with information and advice on managing daily life activities, including dialogue about lifestyle changes at this phase of readjustment.