Study On The Promotion Of Myocardial Protection By Low Intensity Compressive Resistance Training In Rats

Research purposes: To study the effects of blood flow restriction training on muscle strength,bone tissue structural materials and biomechanical properties of rats by applying different exercise interventions to rats,and to preliminarily explore the process mechanism through the detection of bone turnover markers.Research methods: Twenty-four 3-month-old male SD rats(weighing 240 ±20g)were randomly divided into control group(CON),low-intensity training group(LIRT),high-intensity training group(HIRT),and low-intensity compression training group(LIBFR)for 6 weeks.The control group did not receive any intervention;The low-intensity training group received 30% MVCC weight-bearing ladder climbing training;The high-intensity training group received 70% MVCC weight-bearing ladder climbing training;The blood flow restriction training group was subjected to 30% MVCC weight-bearing ladder training at the same time as blood flow restriction.Before sampling,measure the final MVCC using the step-up load resistance ladder;The subjects were killed and collected rat skeletal muscle within 24 hours.Blood and heart samples were collected.The general morphology of myocardial tissue was observed by HE staining.The contents of NO,CK-MB,c Tn1 in serum and SOD and MDA in myocardial tissue were measured by ELISA.The expression of Bcl-2,Bax,Nrf2 and Keap1 protein in myocardial tissue was detected by Western Blot.Research results: Maximum strength test: Compared with CON group,MVCC of LIRT,HIRT and LIBFR groups were significantly increased(P.Detection of physiological indicators:(1)In terms of NO indicators,there was no significant difference between CON group,HIRT group and LIRT group(P>0.05).Compared with CON group and HIRT group,LIBFR group was significantly improved(P<0.05).(2)CK-MB and c Tn1: Compared with CON group,LIRT group increased(P>0.05);In HIRT group,CK-MB was significantly increased(P<0.05),and c Tn1 was significantly increased(P<0.01);LIBFR group decreased(P>0.05).Compared with LIRT group,CK-MB in HIRT group increased significantly(P.CK-MB and c Tn 1 in LIBFR group were lower than those in HIRT group(P<0.05).(3)In terms of SOD and MDA,compared with CON group,LIRT group increased SOD and decreased MDA(P>0.05);The concentration of HIRT group was close to that of CON group;SOD increased and MDA decreased significantly in LIBFR group(P<0.05).Compared with HIRT group,the SOD of LIBFR group was significantly higher and the MDA was significantly lower(P<0.05).Biochemical indexes:(1)Antioxidation(Nrf2,Keap1): Compared with CON group,Nrf2 in LIBFR group was significantly increased(P<0.05),and Keap1 was significantly increased(P<0.01);Compared with LIRT group,Nrf2 in HIRT group decreased(P>0.05)and Keap1 increased(P>0.05);Compared with HIRT group,the expression of large Nrf2 and Keap1 in LIBFR group increased(P>0.05).(2)In terms of anti-apoptosis(Bcl-2,Bax),compared with CON group,Bcl-2 in HIRT group was significantly increased(P;Compared with LIRT group,Bcl-2 in HIRT group was significantly increased(P;Compared with HIRT group,LIBFR decreased in Bcl-2 and Bax(P>0.05),and the value of Bcl-2/Bax in LIBFR group was higher than that in HIRT group(P>0.05).Conclusion:1.Low-intensity compression resistance training can effectively increase muscle strength,which can achieve the same effect as traditional high-intensity strength training.2.Low-intensity pressure resistance training can effectively reduce the CK-MB and c Tn I in the serum of rats,promote the secretion of vascular endothelial growth factor NO,reduce the apoptosis of myocardial cells,improve the antioxidant capacity,and play a certain protective role on the myocardium.3.Long-term high-intensity training may cause myocardial microinjury,which is manifested in the significant increase of serum myocardial injury markers and the reduction of nitric oxide.