Associations Between Cardiorespiratory Fitness and C-Reactive Protein in Men

Abstract

Objective-This study examined the association between cardiorespiratory fitness and C-reactive protein (CRP), with adjustment for weight and within weight categories. Methods and Results-We calculated median and adjusted geometric mean CRP levels, percentages of individuals with an elevated CRP (Ն2.00 mg/L), and odds ratios of elevated CRP across 5 levels of cardiorespiratory fitness for 722 men. CRP values were adjusted for age, body mass index, vitamin use, statin medication use, aspirin use, the presence of inflammatory disease, cardiovascular disease, and diabetes, and smoking habit. We found an inverse association of CRP across fitness levels (P for trendϽ0.001), with the highest adjusted CRP value in the lowest fitness quintile ( Key Words: C-reactive protein Ⅲ cardiorespiratory fitness Ⅲ men E levated plasma C-reactive protein (CRP) levels have been prospectively associated with increased risk of cardiovascular disease (CVD) in apparently healthy individuals. [1][2][3][4] There is an abundance of reports on the positive association between weight and CRP, and investigators have also shown that reduction in weight produces a reduction in CRP concentrations. [5][6][7][8][9][10][11] We have reported previously that fitness has beneficial effects on mortality and CVD risk factors that are independent of weight and evident within weight classifications. [12][13][14][15][16] Thus, when the relationship between weight and CVD risk factors or clinical outcomes is assessed, it is important to account for exercise habits or fitness level.There are only a few available studies examining the effect of regular exercise or exercise training on resting levels of CRP. 10,17,18 Geffken et al 17 found the amount of regular physical activity to be inversely related to CRP in a healthy elderly population, and Rohde et al 18 reported that healthy men who exercise Ͼ1 time a week had lower mean CRP than men who did not exercise at least once a week. Mattusch et al 19 found that 9 months of marathon training resulted in a 31% decrease in CRP (nϭ12), and Smith et al 20 reported a nonsignificant (Pϭ0.12) decrease in CRP (Ϫ35%) after 6 months of exercise training in individuals (nϭ43) at high risk for ischemic heart disease. Although these studies provide evidence that regular exercise may reduce CRP values, each lacks either generalizability, adjustment for weight, a reliable measure of regular physical activity, or an adequate number of participants.Cardiorespiratory fitness is an objective laboratory measurement that reduces the misclassification bias that often results from self-reports of physical activity. Although cardiorespiratory fitness has a genetic component, it is primarily determined by habitual physical activity. 21,22 To our knowledge, there are no available reports on the association of cardiorespiratory fitness and CRP. The purpose of the present study was to examine the association between cardiorespiratory fitness and CRP, with adjustment for weight and also within weight categories. Understanding the relationsh...

Diet or exercise: what is more effective in preventing or reducing metabolic alterations?

“…Inflammatory cytokines might act by impairing insulin-mediated glucose uptake, inhibiting insulin signaling, and increasing the release of free fatty acids from adipose tissue (31). Regular training suppressed the production of CRP and proinflammatory cytokines (31)(32)(33). Accordingly, we found significant inverse relationships between exercise levels and CRP values.…”

Metabolic Syndrome, Obesity, and Mortality

“…There are several previously unknown, emerging risk factors for CVD, some of which may be positively affected by enhanced CRF. For example, C-reactive protein levels, which have been linked with an increase in CVD risk in apparently healthy individuals (31,32), have been shown to be inversely related to CRF (33,34). Recent studies have also demonstrated that C-reactive protein adds to MetS in the prospective prediction of CVD and diabetes (3,35).…”

Associations of low-grade inflammation with physical activity, fitness and fatness in prepubertal children; the European Youth Heart Study

“…[17][18][19][20][21] However, it has been suggested that the beneficial effect of physical activity and CVF on low-grade inflammation might be mediated by body fat. [22][23][24] None of the above-mentioned studies have used objective measures of physical activity, such as accelerometry. Questionnairebased assessment of physical activity, which is the most common subjective method, is imprecise, especially in children.…”