The Comparation Of Effects Between Conventional Resistance Training And Blood Flow Restriction Resistance Training On Elbow Flexion And Extension Strength

Purposes:This study compared the effects of conventional resistance training and blood flow restriction resistant training on muscular maximal strength,power strength and strength endurance of unliteral side(dominant side)on elbow flexion and extension,and discussed the advantages and disadvantages about the two methods.And the effects of the cross-transfer effects of the two methods on the three different kinds of strength were also investigated after training.Methods: 68 senior male students without fitness habits were recruited and randomly divided into 6 groups :(1)Traditional resistance training group(RT1,n=11);(2)Blood flow restriction training group(BFRT1,n=11);(3)Fast contraction resistance training group(RT2,n=10);(4)Fast contraction blood flow restriction training group(BFRT2,n=11);(5)Traditional fatigue resistance training group(RT3,n=12);(6)Fatigue blood flow restriction training group(BFRT3,n=12).Unilateral elbow flexion and extension strength training was conducted at low load(30% 1RM)in each group for 6 weeks,twice a week,with an interval of not less than 48 hours.The BFRT groups applied 160 mm Hg of pressure to the upper extremity on the training side and reapplied pressure after intermittent release.Body composition,bilateral upper arm circumference and isometric muscle strength were tested before and after 6 weeks.And the surface electromyographic signals were collected at the same time as the isometric tests.Results:(1)There was a significant increase in arm circumference on the trained side for RT1 and BFRT2(p<0.05)and on the non-trained side for RT1,BFRT1,RT2 and BFRT2(p<0.05),with no statistical difference between the groups.(2)Peak torque:there was a significant improvement on bilateral elbow flexion and extension for BFRT1 and BFRT2,and on trained elbow extension and non-trained elbow flexion and extension for RT1,and on biliteral elbow extension for RT3(p<0.05).(3)Mean power: there was a significant improvement on bilateral elbow flexion and extension for BFRT2,and on trained elbow flexion and extension for BFRT3,and on trained elbow extension for RT1 and RT3,and elbow extension on trained side for BFRT1 and non-trained side for RT2 and BFRT3,and on non-trained elbow flexion and extension for RT1,BFRT1 and RT3(p< 0.05).(4)Work fatigue: there was a significant improvement on bilateral elbow extension for BFRT1,and on the trained elbow extension for RT3(p<0.05).(5)Integral electromyography(i EMG): there was a significant decrease on the non-trained side BP for BFRT3 under 60°/s,and on the trained side BP and the non-trained side TP and BR for BFRT1,and on the trained side TP for RT2,RT3 and BFRT3,and on the non-trained side BP and BR for BFRT3 under 240°/s(p < 0.05).(6)Root mean square amplitude(RMS): there was a significant increase on the trained side TP for BFRT2 under60°/s and 240°/s(p<0.05),we also detected a trend to improvement on other muscles on biliteral side for BFRT2(p>0.05).(7)Median frequency(MF): there was a significant increase on the trained side BP for BFRT1,RT2 and BFRT2,and on the biliteral side BR for BFRT1 and RT2,and on the non-trained side BP and BR for BFRT2(p<0.05).(8)Mean power frequency(MPF): there was a significant improvement on the trained side BP and biliteral side BR for BFRT1,and on the biliteral BR and non-trained side BP for RT2,and on the non-trained side BR for BFRT2,and on the trained side TP for RT3,and on the non-trained side BP for BFRT3 under 180°/s(p < 0.05).(9)Except for no significant difference in work fatigue between the groups,peak torque,mean power,RMS,MF and MPF all improved to different degrees,with the most significant improvement in each index in BFRT1 and BFRT2.Although the i EMG values decreased to different degrees in all groups,the rate of i EMG improvement in the BFRT group was higher than that in the RT group in general,with the improvement of i EMG in BFRT2 being dominant.Conclusions: In general,(1)Compared with the three RT groups,both BFRT1 and BFRT2 can improve the flexion and extension maximal muscle strength on the trained elbow significantly.(2)Three BFRT groups,RT1 and RT3 can improve power strength on the trained side to varying degrees,with the BFRT2 having the most significant improvement.(3)Both BFRT1 and RT3 can improve the extension elbow endurance strength on the trained side,but no significant differences between groups were detected.(4)There was a significant cross-transfer effect for the T1 and T2,but the difference between the groups was not significant.(5)Muscle recruitment: BFRT groups compared to RT groups was beneficial to the increased synchronization of fast motor unit discharge and the number of motor unit recruitment of the trained side,but could not significantly increased discharge frequency and discharge intensity of the trained side.(6)RT1 and BFRT2 improved upper arm circumference on the training side.both T1 and T2 groups improved upper arm circumference on the non-trained side,but there was no difference in the degree of improvement.