The present study investigated the effects of Hovenia Dulcis (HD) fruit extract powder on the improvement of physical activity, especially exercise capacity. Forty mice were divided into 4 groups including normal controls, negative controls, 100 (HD-100) and 200 (HD-200) mg/kg HD fruit extract powder groups for 5-times exercises using treadmill. Normal control did not performed treadmill running but others did 5-times for 10 days. HD fruit extract powders were administrated orally one-times per day for 10 days before treadmill exercise and normal and negative controls were fed with excipient water. After 5-times exercise, blood biochemical analysis showed that aspartate aminotransferase (AST), lactate dehydrogenase (LDH) and creatine phosphokinase (CK) activities and blood lactate concentration were statistically increased in negative controls than in normal controls. They were decreased in HD fruit extract powder groups, compared with negative controls. These results were considered as the effects of HD fruit extract powders on reduced tissue damages during exercise. Other measured indices did not reveal remarkable differences. All together, these results suggest that HD fruit extract powders may enhance the exercise performance by recovering the exercise-fatigue via blood lactate concentration by reducing blood LDH activity and via reduction of blood CK and AST activity.