Title: Gamma tocopherol supplementation prevents exercise induced coagulation and platelet aggregation

INTRODUCTION: Strenuous exercise in sedentary individuals increases the acute risk of atherothrombotic events and depletes endogenous antioxidants. Supplementation with the antioxidant tocopherol ameliorates the risk; however it is unclear whether α-tocopherol, γ-tocopherol or a combination of both is more efficacious. We therefore measured the effects of γ-,αand mixed tocopherol supplementation on blood thromboinflammatory markers after an acute bout of endurance exercise. MATERIALS AND METHODS: 36 healthy, sedentary volunteers were randomly assigned to a 6 week antioxidant supplementation regimen of either low dose (300 mg every other day) or high dose (300 mg per day) γ-tocopherol, low dose (400 IU every other day) or high dose (400 IU per day) αtocopherol, a combination (alternating 400 IU α-tocopherol or 300 mg γ-tocopherol per day), or a soy placebo control. Volunteers exercised at 70% of peak O2 uptake for one hour, or until volitional fatigue before and after intervention and laboratory parameters including full blood examination, platelet aggregation, lipid profile and inflammation markers measured. RESULTS: γ-tocopherol ameliorated the exercise-induced hyper-coagulable and hyper-aggregatory states following exercise, reducing collagen induced platelet aggregation below baseline (89% of baseline, p<0.01). Lipid profile, inflammation markers or platelet count were not affected. CONCLUSION: Chronic supplementation with γtocopherol, but not α-tocopherol prevented exercise-induced platelet aggregation and hypercoagulability. Furthermore, supplementation with high dose γ-tocopherol in combination with exercise significantly reduced collagen-induced platelet aggregation below pre-exercise levels. Therefore γtocopherol in the absence of high dose α-tocopherol may enhance the beneficial effects of exercise on haemostatic and cardiovascular function.