Effects Of Blood Flow Restriction Combined With Whole-body Vibration Stimulation On Lower Extremity Myoelectric Activity And Metabolic Accumulation In Male College Students

Objective: Blood flow restriction training(BFR)and whole-body vibration training(WBV)are a new type of training method.These two training methods have a positive effect on improving sports performance.However,little research has been done on the training methods combining the two.The objective of this study was to investigate the effect of BFR with WBV on myoelectric activity and metabolic accumulation under different training methods.It hopes to provide a certain theoretical basis for coaches,athletes and the general public to choose a reasonable training method.Methods: Twelve healthy men were recruited.All subjects underwent four experimental:(1)Control group(CON,with neither BFR nor WBV);(2)Blood flow restriction training group(BFR group);(3)Whole-body vibration training group(WBV group);(4)Blood flow restriction with whole-body vibration training group(BFR+WBV group).In each group,an isometric squat movement with knee flexion of120 ° was used for intervention.Each group performed the squat movement for 120 s,an interval of 60 s,and repeated 3 times.The BFR group underwent pressurization intervention at the proximal end of both thighs during the squat movement.The WBV group underwent whole body vibration stimulation at a vibration frequency of 30 Hz and an amplitude of 4 mm during the squat movement.The BFR+WBV group was simultaneously underwent pressurization and vibration stimulation.The surface electromyograph was used to collect the electromyographic signals(EMG)in the subject's right lower limb six muscles throughout the experimental process.These six muscles are: Vastus lateralis(VL),Vastus medialis(VM),Rectus femoris(RF),Tibialis anterior(TA),Gastrocnemius medialis(GM)and Soleus(SOL).Before each training,immediately after the training and 15 minutes after the end of the training,the blood of the right fingertip of the subject was collected to determine the blood lactic acid concentration.Results:(1)Myoelectric activity results: The EMG signal of different groups showed an increasing trend with time,but the increase of EMG was different in different groups.The order of myoelectric amplitude was increased from CON(20%MVC)to BFR(32% MVC)to WBV(44% MVC),and finally to WBV+BFR(75%MVC)(P <0.05).Among them,the BMG+WBV had higher EMG amplitude in VL,VM,RF,GM,and SOL than the CON(P <0.05);The EMG amplitude of BFR + WBV group in VL,VM and SOL was higher than the BFR(P <0.05);The EMG amplitude of BFR+WBV in VM was higher than that of WBV(P <0.05).In addition,VL,VM,and RF during the last 5 seconds of training were higher than those during the first 5seconds(P <0.05).(2)Metabolic accumulation results: The blood lactic acid concentration also increased over time.The blood lactic acid concentration of CON,BFR,WBV and WBV+BFR immediately after training were higher than before training(P <0.05).The blood lactic acid concentration in the WBV+BFR increased more significantly than the other three groups(P <0.05).Immediately after exercise,the blood lactate of the WBV+BFR was significantly higher than CON(P <0.05),BFR(P <0.05),and WBV(P <0.05).Conclusion: Blood flow restriction training and whole-body vibration stimulation training methods can increase the acute effects of BFR or WBV alone,but the training mode of BFR + WBV makes the effects of lower limb myoelectricity and metabolic accumulation more significant.This shows that the combined effect of blood flow restriction training combined with whole body vibration training is better than single training.