While regular participation in physical activity helps optimize physical health and psychological well being, less than 1/3rd of adults engage in adequate levels of exercise to reap these important benefits. Understanding how to foster an environment in exercise settings that help people feel comfortable, safe, supported by others and motivated to be regular exercisers is an important area of inquiry. Limited research has examined the relationship between exercise participants' perceptions of the environment in their health club/exercise classes to their motivational responses with regard to physical activity. The purpose of this study was to examine exercise participants' perceptions of a task-involving and caring climate within structured, group aerobic exercise classes to their self-reported intrinsic motivation, commitment to exercise, and social physique anxiety. Participants were college students (N=204) enrolled in university aerobic physical activity classes including spinning, aerobic kick boxing, aerobic water exercise, and aerobics. During the last 2 weeks of the 17 week semester long courses, students were invited to complete a survey that included the following measures: Perceived Motivational Climate in Sport Questionnaire (adapted for exercise setting by Henry, 2002); Caring Climate Scale (CCS; Newton, et al, 2008); Intrinsic Motivation Inventory (IMI; McAuley, et al, 1989); Exercise Commitment Scale (ECS; Alexandris, et al, 2002); and Social Physique Anxiety Scale (SPAS; Motl & Conroy, 2000). Correlational analyses revealed that when exercise participants perceived a caring and task-involving climate in their courses they reported significantly higher effort, enjoyment, perceived competence, and commitment to future exercise, and lower tension and social physique anxiety. Further, exercise participants who perceived an ego-involving climate in their classes reported significantly less enjoyment, effort, perceived competence; lower commitment and greater tension. Overall, these results suggests that when participants perceive a caring and positive climate in their exercise classes they are more likely to maximize their physical activity experiences. It may be that exercise leaders would benefit from intentionally fostering a positive environment where they recognize individuals' effort and improvement, and encourage respectful and supportive interactions among class members. Keyword(s): adult physical activity/fitness, exercise/fitness/physical activity, research