Objective:To study the effects of Morindae Officinalis Radix（RMO） on the exercise capacity and mitochondrial antioxidant capacity of rats.Method: The high-intensity endurance training was used to establish model.Fifty-five Wistar rats were divided into 5 groups（n=10 for group）:motionless group（C group）

exercise group（T group）

exercise ig low-dose RMO group of（RMOL group）

exercise ig middle-dose of RMO group（RMOM group）

exercise ig high-dose of RMO group（RMOH group）.The dose was 4

8

12 g · kg-1 · d-1

ig volume 5 mL · kg-1

administration lasted 6 weeks.At 24 h after the last training

weight

exhaustive swimming time

the various indicators of fatigue-related content were measured in mitochondria

such as malondialdehyde（MDA）

etc.Result:Weight of each RMO group was greater than the T group（P<0.05）

swimming time was longer than T group（P<0.01）.Exhaustive swimming increased the MDA conten in T group and RMO groups（6.06±0.24）

（5.07±0.56）

（5.08±0.79）

（5.09±0.53） μmol · L-1

and that the RMO groups was significantly lower than the T group（P <0.01）.superoxide dismutace（SOD）

glutathi one peroxidace（GSH-Px） activity was significantly decreased [T-group and RMO groups

SOD decreased to（211.35±20.37）

（255.85±10.31）

（258.98±8.24）

（263.31±12.69）U · mL-1

GSH-Px decreased to（55.72±14.23）

（70.64±5.83）

（70.96±4.96）

（71.38±5.06）U · mg-1]

and the RMO group was significantly higher than the T group（P<0.01）.Conclusion: RMO has the effects on improving the exercise capacity and the mitochondrial antioxidant enzyme activity.