Objective To explore the difference of brain function remodeling in patients with differ-ent motor ability and record the brain function index of patients returning to exercise 2 years after an-terior cruciate ligament reconstruction(ACLR).Methods Patients undergoing ACLR in year 2017 and 2018(2 years after ACLR)were selected and randomly divided into a return-to-exercise(CP,n=7)group,a non-return-to-exercise(NP,n=7)group.Moreover,8 healthy counterparts of the CP group were chosen into a healthy control(HC)group.Resting state functional magnetic resonance imaging(rs-fMRI)was used to obtain the blood oxygen level dependent signals,and the amplitude of low-frequen-cy fluctuation(ALFF)was computed across the typical band(0.01～0.08 Hz),sub-band Slow-4(0.027～0.073 Hz)and Slow-5(0.01～0.027 Hz).Meanwhile,brain maps were obtained and two-sample t-tests were performed among different groups(P<0.005).Results In the typical frequency band,the average ALFF value was higher in the CP and HC groups than the NP group for the Cerebelum_Crus1,but lower in the CP group than the NP group for the Occipital_Mid,higher in the CP group than the HC group for the Putamen and higher in the NP group than the HC group for the Frontal_Mid_Orb.More-over,in the Slow-4 band,the ALEF level was lower in the CP group than the NP group for the Oc-cipital_Mid,higher in the CP group than the HC group for the Putamen,and higher in the NP group than the HC group for the Frontal_Mid_Orb and cerebellum_Crus2.However,in the Slow-5 band,the ALEF values were higher in the CP group than the NP group for the Occipital_Inf and Precen-tral,but lower for the caudate.In the same band,those values were higher in the CP group than in the HC group for the Cerebellum_Crus1,but lower in the NP group than the HC group for the Cere-bellum_Crus1 and Supp_Motor_Area,and higher in the NP group than the HC group for the Fron-tal_Mid_Orb.Conclusion The patients returning to exercise after ACLR have higher cerebellar remodel-ing and lower visual compensation than those not,and display higher basal ganglia and cerebellar nerve remodeling than healthy controls,suggesting that functional compensation occurs in the former pa-tients.Moreover,Slow-4,Slow-5 and other sub-bands can complement the classical frequency bands and are worthy of further study.