The objective of the present study was to examine psychological aspects of intra- and interpersonal learning for patients with Type 2 diabetes, hypertension and dyslipidemia treated with Exercise on prescription. The research design consists of a qualitative investigation of 30 patients in Denmark undergoing a community-based exercise treatment at baseline, a post-intervention investigation after four months and a follow-up one year after the start of intervention. The results demonstrated that, for the majority of the participants, interaction under group conditions contributes to maintaining the commitment to exercise. For a corrective emotional experience - a correction of an emotional situation a person could not handle in the past - to occur requires two conditions: the group and the environment must be experienced as sufficiently safe, and there must be feedback to permit reality-testing. However, existential psychological aspects such as fear of dying or the universality of suffering triggered, but could not sustain, a change in health behavior. The article concludes that behavioral change is strengthened by interaction with health personnel and with the training group. These new insights likewise demand an increased focus on the human resources of general practitioners or physiotherapists who handle the training. They should learn about their supportive role for the participants, the regressive urges of the participants and the benefits of promoting group relations.