Abstract.[Purpose] The effects of exercise and food consumption on the oxidative stress regulation system were studied using 45 male ICR mice. [Subjects and Methods] The mice were randomly divided into two groups: a control group (CO group) and a group consuming a reduced form of coenzyme Q10 (H 2 CoQ10: QH) (QH group). Both groups were made to run on a treadmill for animals (TM) twice and the changes in their running time were measured. For the oxidative stress regulation system, plasma oxidative stresses (d-ROM test) and plasma antioxidant potential (BAP test) were measured before and after treadmill running with analytical equipment for reactive oxygen and free radicals, and then the BAP/d-ROM ratio was calculated.[Results] The measurements and calculations showed a significant increase in the running time of the QH group. With respect to the oxidative stress regulation system, no significant change was observed in the BAP/d-ROM ratio.[Conclusion] These results showed that a single consumption of QH produced an effect on exercise, but had no effect on the oxidative stress regulation system.