PURPOSE: After menopause, leisure physical activity (PA) levels seem to decline for reasons that are not completely understood. This study examines the associations between PA, lapses in PA, and psychosocial factors in early postmenopausal women. METHODS: This cross-sectional analysis included 497 women from the Women on the Move through Activity and Nutrition study. PA was assessed with a past-year, interviewer-administered Modifiable Activity Questionnaire. Measures of activity lapses of ≥ 2 wk in the past 6 months, exercise decision making, processes of change, and self-efficacy were collected along with Beck Depression Inventory, State-Trait Anxiety Inventory, Cohen Perceived Stress Scale, and Short Form-36. RESULTS: Mean age of participants was 56.9 yr. Compared with less active women, women with significantly higher activity levels reported greater exercise self-efficacy (r = 0.31), more frequent use of behavioral exercise processes of change (r = 0.31), greater perceived benefits for PA (r = 0.22), and better physical quality of life (r = 0.16) (all P < 0.001). Women reporting no activity lapses had higher reported activity levels than regularly active women with lapses or occasionally active women with lapses (P < 0.0001 for trend). Of the women who reported lapses, 24% reported low self-confidence, 43% reported difficulty controlling their weight, and 55% reported difficulty maintaining their diet when they lapsed from PA. Thirty-nine percent of women reporting lapses did not resume PA (i.e., relapsed to inactivity). Higher anxiety and depressive symptoms, and less frequent use of behavioral exercise processes of change, were associated with relapse to inactivity. CONCLUSIONS: Future interventions for early postmenopausal women should consider psychosocial factors when attempting to encourage and maintain higher levels of PA. Addressing and preventing PA lapses may help to achieve PA goals in this population. ©2007The American College of Sports Medicine.