The authors investigated vigorous physical activity, psychological well-being, and self-reported illness during transition to first-year university life in a sample of 175 Canadian under-graduates. At the completion of their first year of university study, participants completed retrospective measures assessing vigorous physical activity, upper respiratory infectious illness (URI), doctor visits, as well as measures of psychological well-being. Based on nationally recommended (US Department of Health and Human Services) standards, 61% of students reported engaging in adequate levels of vigorous activity during their first year at university. The authors found no differences in URIs between sufficiently and insufficiently active students. However, insufficiently active students scored lower on psychological well-being and were twice as likely to have consulted a physician regarding an illness compared with sufficiently active students. (Contains 2 tables.)