Effect of Exercise Training Modality on C-reactive Protein in Type 2 Diabetes

Purpose: Type 2 diabetes is associated with increased risk of cardiovascular disease and elevated C-reactive protein (CRP) levels. Aerobic exercise training has been shown to improve CRP; however, there are limited data evaluating the effect of other exercise training modalities (aerobic, resistance, or combination training) in individuals with type 2 diabetes.

Methods: Participants (n = 204) were randomized to an aerobic exercise (aerobic), resistance exercise (resistance), or a combination of both (combination) for 9 months. CRP was evaluated at baseline and at follow-up.

Results: Baseline CRP was correlated with fat mass, waist circumference, body mass index, and VO(2peak) ̇(P < 0.05). CRP was not reduced after aerobic (0.16 mg·L(-1), 95% confidence interval (CI) = -1.0 to 1.3 mg·L(-1)), resistance (-0.03 mg·L(-1), 95% CI = -1.1 to 1.0 mg·L(-1)), or combination (-0.49 mg·L(-1), 95% CI = -1.5 to 0.6 mg·L(-1)) training compared to control (0.35 mg·L(-1), 95% CI = -1.0 to 1.7 mg·L(-1)). Changes in fasting glucose (r = 0.20, P = 0.009), glycated hemoglobin (HbA1c) (r = 0.21, P = 0.005), and fat mass (r = 0.19, P = 0.016) were associated with reductions in CRP but not with change in fitness or weight (P > 0.05). There were significant trends observed for CRP among tertiles of change in HbA1c (P = 0.009) and body fat (P = 0.040).

Conclusions: Aerobic, resistance, or a combination of both did not reduce CRP levels in individuals with type 2 diabetes. However, exercise-related improvements in HbA1c, fasting glucose, and fat mass were associated with reductions in CRP.