The present invention relates to an anti-oxidant composition having reducing effect on plasma lipid peroxidation and plasma TNF-; concentrations in a subject, which comprises an effective anti-oxidant amount of an end-product of kefir manufacturing process for oral administration to the subject. The apparatus includes a master cylinder 4 that generates hydraulic brake pressure by a driver’s brake operation, and a stroke simulator 5 that creates an artificial operation reaction force of a brake operation member when the brake fluid flown out of the master cylinder 4 enters the stroke simulator 5. In one embodiment, the device comprises a support member to be worn by the person.