This paper reviews the literature concerning factors at the individual level associated with regular exercise among older adults. Twenty-seven cross-sectional and 14 prospective/longitudinal studies met the inclusion criteria of a mean participant age of 65 years or older. The findings are summarised by demographics, exercise experience, exercise knowledge, physiological factors, psychological factors, activity preferences and perceived social influences. In general, education and exercise history correlate positively with regular exercise, while perceived physical frailty and poor health may provide the greatest barrier to exercise adoption and adherence in the elderly. Social-cognitive theories identify several constructs that correlate with the regular exercise behaviour of older adults, such as exercise attitude, perceived behavioural control/self-efficacy, perceived social support and perceived benefits/barriers to continued activity. As well, stage modelling may provide additional information about the readiness for regular exercise behaviour among older adults. However, relatively few studies among older adults exist compared with middle-aged and younger adults. Further, the majority of current research consists of cross-sectional designs or short prospective exercise trials among motivated volunteers that may lack external validity. Future research utilising longitudinal and prospective designs with representative samples of older adults will provide a better understanding of significant causal associations between individual factors and regular exercise behaviour.