Objective: Our goal was to examine the effects of regular endurance exercise on plasma GlycA levels, a novel NMR-derived biomarker of systemic inflammation.
Methods: We examined NMR-derived plasma GlycA levels before and after 5-6 months of exercise training in 1,194 adults from four studies: APOE (N=104), DREW (N=298), GERS (N=78), HERITAGE (N=714). We used unadjusted and adjusted general linear models to evaluate changes in GlycA with regular exercise across sex-specific quartiles of baseline GlycA in all studies combined.
Results: At baseline, the combined participants (69% white, 66% female) were an average of 42.5 (15.4) years old with a mean BMI of 28.1 (5.8) kg/m2. Exercise training resulted in a decrease in GlycA of 5.6 (42.0) μmol/L (P<0.0001) across all studies. In the unadjusted model, only the fourth quartile of baseline GlycA showed a mean decrease in GlycA with exercise training, while a linear decrease across Q2 to Q4 was observed in the adjusted model (Figure 1). In both models, Q4 showed the greatest decrease in GlycA.
Conclusions: Regular exercise tended to decrease GlycA levels across four diverse, standardized exercise training studies. Our results suggest that the individuals at highest risk appear to benefit the most from regular exercise in terms of GlycA.
Figure 1. Mean change in GlycA after exercise training by baseline GlycA quartile in four exercise studies combined.
P<0.0001 for trend in both the unadjusted and adjusted analyses. Unadjusted analysis included three dummy variables representing the four study groups. Adjusted analyses included age, sex, race, baseline BMI, baseline VO2max, baseline GlycA quartile, and three study group dummy variables as covariates. Sex-specific baseline GlycA quartiles in combined group (M/F): Q1: <282/<317; Q2: 283-323/317-356; Q3: 324-370/318-395; Q4: >370/>395