Hemostatic Alterations With Exercise Conditioning in NIDDM

Various parameters of coagulation and fibrinolysis were measured in 13 men (aged 54 ± 3 yr) with non-insulindependent diabetes mellitus (NIDDM) before and after 12-14 wk of exercise training. Subjects exercised for 30 min 3 times/wk at 70% of maximum O₂ consumption (Vo_2max). Training increased Vo_2max by 12.5% but did not alter body weight, relative body fat, blood pressure, cholesterol, triglycerides, or high-density lipoprotein cholesterol. Slight downward trends were apparent for fasting glucose and insulin, but glycosylated hemoglobin was unchanged. There were no changes in coagulation parameters of plasminogen, hematocrit, or α₂-antiplasmin. Plasma fibrinogen (303 ± 24.2 vs. 256 ± 12.3 mg/dl) and fibronectin (380 ± 41.9 vs. 301 ± 22.2 μg/ml) were significantly reduced (P < 0.02) by exercise conditioning. Three assays of fibrinolytic activity (tissue plasminogen activator, euglobulin lysis time, and an isotopic measure of fibrinolysis) confirmed that neither basal fibrinolysis nor the fibrinolytic responses to venous occlusion and maximal exercise were significantly altered. Exercise conditioning may have antithrombotic effects in NIDDM by reducing plasma fibrinogen and fibronectin. Although the significance of the fall in fibronectin awaits further studies, the reduction in plasma fibrinogen gives a rationale for the use of exercise training in men with NIDDM.