Physical activity in primary stroke prevention: just do it!

S troke is a preventable disease. Well-documented, modifi-able risk factors for stroke include hypertension, diabetes mellitus, dyslipidemia, obesity and body fat distribution, cigarette smoking, atrial fibrillation, heart disease, and physical inactivity. There is a wealth of information supporting physical activity (PA) as an important component of primary stroke prevention strategies. The proposed mechanism is that PA improves vascular function and stroke risk factors. 3 The well-known health benefits of regular PA include reducing the risk of hypertension, type 2 diabetes mellitus, depression, and obesity, as well as control of these risk factors. there are no clinical trials data demonstrating the efficacy of PA in reducing stroke incidence, partially because of the long follow-up required to achieve a sufficient number of events. The next best evidence comes from nonrandomized cohort studies where the consistency of results strongly supports the benefit of PA in primary stroke prevention (Class I, Level of Evidence B). 1 The purpose of this review is to summarize the terminology and measurement of PA, synthesize the results of studies of PA and stroke risk in men and women, and describe how PA can ameliorate the effects of stroke risk factors, such as diabetes mellitus and hypertension. The challenges with PA research will also be discussed, as well as recommendations for future research. PA is a complex behavior that can incorporate different elements , including occupational or leisure time PA, commuting, sport, walking, and exercise training. The accepted definition of PA used by most researchers is " any bodily movement produced by skeletal muscles that results in energy expenditure " (p. 126). 12 This differs from exercise, a subset of PA defined as " PA that is planned, structured, repetitive and purposeful in the sense that improvement or maintenance of one or more components of physical fitness is an objective " (p. 128). 12 Generally, epidemiological studies that rely on self-report intend to measure PA, but it is not always clear that participants understand the difference between PA and exercise when they complete surveys or questionnaires. An alternative approach is to directly measure the physiological variable cardiorespiratory fitness using maximal or submaximal exercise tests but this is not feasible in large scale studies. The approach used in many longitudinal cohort studies, such as the Framingham Heart Study (FHS), the Nurse's Health study, and the REasons for Geographic And Racial Differences in Stroke (REGARDS), is to ask about the frequency …