Abstract
Physical Activity (PA), visceral adipose tissue (VAT), and inflammation are key modulators of metabolic disease risk. However, the relative contribution of VAT and PA on inflammation and the variability of inflammatory markers over time is not clear. It was hypothesized that individuals with lower inflammation would have a greater volume of PA and lower VAT.
PURPOSE: To determine the variability of inflammation over time and the differential impact of sedentary, light, moderate, and vigorous PA as well as VAT on measures of inflammation in metabolically healthy overweight and obese (MHO) adults.
METHODS: Preliminary analysis (n = 13) in an ongoing study (expected n = 36) of adults 18-70 y with waistline circumference > 35 in (women) and > 40 in (men) was completed for fasting/resting concentrations of interleukin (IL)-1β, IL-6, IL10, IL17-, IL-23, interferon gamma (IFN-γ), tumor necrosis factor-α (TNF-α), and granulocyte-macrophage colony stimulating factor (GM-CSF) before and after a 12-week period. PA using ActiGraph accelerometer data was collected for seven consecutive days in the week prior to re-test inflammation markers. PA data was classified as sedentary (0-150 count), light (150-2689), moderate (2690-6166) and vigorous (>6167). VAT was measured via bioelectrical impedence analysis (BIA) before and after the 12-week period.
RESULTS: Test, re-test values of all mean cytokine concentrations were highly correlated (r = 0.87-0.99, p < 0.01). Contrary to our hypothesis, no significant correlation between total PA volume and inflammatory markers was identified. The only significant inverse correlations identified were for average time (accumulated minutes) spent in moderate PA and IL-10 (p = 0.04) and light PA and IL-6 (p = 0.04). VAT was positively correlated with Il-17 (p = 0.04), IFN (p = 0.02), and IL-10 (p < 0.01) at baseline and with IL-17 (p = 0.02), IL-10 (p < 0.01), and IL-1B (p = 0.03) at the end of 12 weeks.
CONCLUSION: The current data suggest that repeat measures of inflammation are consistent over a 12-week period. In addition, VAT more closely correlated with inflammatory markers in test, re-test analysis than PA. The unexpected lack of correlation between volume of PA and chronic inflammatory markers warrants additional research.