Exercise training induces thrombogenic benefits in recent but not late postmenopausal females

Although regular physical activity is known to improve cardiovascular health in men, evidence for its beneficial effects in postmenopausal females is less convincing and it remains unclear whether initiation of exercise training soon after, rather than many years after menopause impacts the magnitude of training-induced adaptations. We evaluated exercise-induced changes in markers of thrombotic risk and conduit artery function in recent(<= 5yr) compared with late >=(10yr) postmenopausal females. Fourteen recent(<= 5yr) and 13 late(>= 10yr) healthy postmenopausal females completed 8 wk of regular intensive exercise training, consisting of floorball and cycling. Markers of thrombotic risk and vascular health were assessed before and after the intervention, and data were analyzed using a linear mixed model. Exercise training reduced markers of thrombotic risk, including an 11% reduction (P = 0.007) in agonist-induced platelet reactivity and a reduction (P = 0.027) in incipient clot microstructure (similar to 40% reduction in clot mass) in the recent(<= 5yr) but not the late(>= 10yr) (P = 0.380; P = 0.739, respectively) postmenopausal females. There was no change in conduit artery function, as measured by brachial (recent <=(5yr), P = 0.804; late >=(10yr), P = 0.311) and popliteal artery (recent <=(5yr), P = 0.130; late >=(10yr), P = 0.434) flow-mediated dilation. Only the late >=(10yr) postmenopausal females exhibited an increase (by 9.6%, P = 0.022) in intracellular adhesion molecule-1 levels after training, which may have impacted the thrombogenic adaptation in this group. These findings suggest that 8 wk of high-intensity exercise training reduces thrombotic risk in recent <=(5yr), but not late(>= 10yr) postmenopausal females. Thus, regular physical activity initiated soon after, rather than many years after menopause and at a higher age, may be more efficient for reducing thrombogenic risk.