Prospective study of physical fitness, adiposity, and inflammatory markers in healthy middle-aged men and women

Abstract

BackgroundPhysical fitness may provide cardiovascular benefits in the obese. ObjectiveWe prospectively examined the associations between inflammatory markers and fitness, body mass index, and central adiposity. DesignHealthy men and women (n = 176) were recruited from the Whitehall II epidemiologic cohort. At baseline we measured physical fitness and adiposity, and blood was drawn for the assessment of inflammatory markers [C-reactive protein (CRP) and interleukin-6 (IL-6)]. We subsequently assessed inflammatory markers and adiposity at the 3-y follow-up visit. ResultsBody mass index, but not physical fitness, was independently associated with IL-6 and CRP at follow-up. Weight gain was also associated with CRP at follow-up. Compared with fit-lean participants, the unfit-overweight participants had significantly higher concentrations of CRP (adjusted β: 0.67; 95% CI, 0.31, 1.00) and IL-6 (adjusted β: 0.28; 95% CI: −0.06, 0.49) at follow-up. In contrast, the fit-overweight and unfit-lean participants did not differ significantly from the fit-lean participants after adjustments for age, sex, smoking, employment grade, and baseline inflammation. ConclusionsIn participants followed up for 3 y, changes in low-grade inflammation were positively associated with adiposity but not with fitness at baseline. Further attention should focus specifically on overweight-obese participants in relation to physical fitness and cardiovascular disease risk.