IJCS | Volume 31, Nº6, November / December 2018

600 Rissardi et al. Effects of physical inactivity on blood glucose Int J Cardiovasc Sci. 2018;31(6)594-602 Original Article Hypertension In the present study, there was a 28% higher probability of HT in PI individuals. In turn, studies have shown a reduced prevalence of HT related to a higher rate of physical activity. 33,34 Physical activity decreases total peripheral resistance by improving endothelium- dependent relaxation, mainly mediated by a significant increase in vascular nitric oxide (NO) production and/ or decrease in NO scavenging by reactive oxygen species (ROS). Moreover, exercise has also been shown to release several cytokines and anti-inflammatory peptides, which in turn increase NO bioavailability by decreasing ROS production. Exercise-related vasodilation was also associated with the growth of new arterioles and the reduction of nervous sympathetic activity. 34 Metabolic syndrome It was observed a 56% higher probability of MetS in PI individuals. Several studies have found that the practice of LTPA was associated with a reduction in MetS components. 35-37 Longer duration of daily physical activities leads to a lower prevalence of MetS, especially for the components of central obesity and HDL-c levels. 37 Moreover, a recent study showed that middle-aged individuals with MetS who usually perform physical activity had lower arterial stiffness and more favorable cerebral whitematter integrity than their sedentary peers. 38 Lipid parameters The analysis of bootstrap in the PI group showed a tendency for higher levels of lipoproteins (TC, LDL-c and TG), when compared with PA subjects. Physical exercise has shown beneficial effects on plasma lipoproteins, such as decrease in TC, LDL-c, and TG levels. 39,40 Spending less time in sedentary behaviors, and having medium levels of intense physical activitymay be associatedwith amore favorable blood lipid profile. 40 Blood glucose The bootstrapmethod curve showed a rightward shift in the PI group, and, consequently, lower glucose levels in the PA group. Data have shown an inverse association between physical activity and blood glucose. 34,35 Studies have demonstrated that improved blood glucose control is due to increased insulin sensitivity and glucose metabolism promoted by physical exercise. 37 Strengths and limitations Some l imi t a t i ons o f th i s s tudy should be mentioned. First, the guidelines of the American Diabetes Association 18 recommend the confirmation of hyperglycemia through a second blood glucose measurement, which was not performed in this study. However, epidemiological studies, including NHANES, used almost exclusively a single blood glucose measurement for the diagnosis of T2DM. Second, the interference of antilipemic drugs on lipid values determination was not assessed. Third, the association between physical activity and its benefits in preventing CVD risk and T2DM could be better evaluated in a cohort study rather than a cross-sectional one. Nevertheless, this fact does not invalidate the present study since that its main objective was to evaluate the prevalence of physical inactivity in the urban population. The benefits of physical activity could be better assessed through a cohort study, which is not the goal of this study. On the other hand, this population-based, age-stratified study, is unique as it gathers different demographic, epidemiologic and risk factors involved in the association between physical activity, hypertension and CVD in a single sample with a population assessment calculation, which might be extrapolated to other populations. Conclusions This study shows a high rate of physical inactivity in all age groups, higher among women and with differences in the prevalence according to the socioeconomic and educational levels. It also demonstrates a clear association between physical inactivity and the presence of cardiovascular risk factors, mainly hypertension, hyperglycemia and lipid changes, observed by the bootstrap method. Author contributions Conception and design of the research: Cipullo JP, Ciorlia LAS, Cesarino CB, Vilela-Martin JF. Acquisition of data: Cipullo JP, Ciorlia LAS, Cesarino CB, Vilela-Martin JF. Analysis and interpretation of the data: Rissardi GGL, Cipullo JP, Giollo Junior LT, Vilela-Martin JF. Writing of themanuscript: Rissardi GGL, Moreira GC, Vilela-Martin JF. Critical revision of the manuscript for intellectual content: Giollo Junior LT, Zanesco A, Vilela-Martin JF.