| Objective:Growing evidence supports the rela tionship between the complexity and diversity of the gut microbiota and host disease.There is clinical evidence that the gut microbiota and metabolites may be novel preventive and therapeutic targets for cardiovascular an d metabolic diseases.This study aimed to elucidate the effects of 8-week Flexi-Bar exercise intervention on cardiovascular function,gut microbiota and short-chain fatty acids in sedentary middle-aged and elderly women,and to explore the effects of aerobic exercise（AE）on cardiovascular function To investigate the possible mech anism of gut microbiota and short-chain fatty acids affecting cardio vascular function,and to analyze the correlation between cardiovascular function indicator s and gut microbiota after Flix Bar exercise interventi on.Methods:30 sedentary middle-aged and elderly women were randomly divided into the Flexi-Bar exercise group（FE group）and control group（Con group）.FE was given Flexi-Bar exercise intervention for 8 weeks,3 times a week,60 minutes per time,while the control group maintained normal living habits.The related functions of the two groups of subjects were detected and the samples were collected before and after the intervention.The main results were as follows:（1）the vascular endothelial function was measured by flow-mediated vasodilation（FMD）.（2）the body composition of the subjects was detected by the body composition analyzer In Body370.（3）Blood sam ples were collected and the concentrations of e NOS,VEGF,VCAM-1,ICAM-1,and TNF-α in serum of the two groups were quantitatively detected by enzyme-linked immunosorbent assay（Elisa）.（4）the feces of the subjects were collected,the structural composit ion and diversity of intestinal microflo ra were analyzed by 16 sr RNA sequencing,and the contents of acetic acid,propionic acid,isobutyric acid,butyric acid,isovaleric acid,and valeric acid in the intestinal tract were detected by short-chain fatty aci d（SCFA）.This paper will also analyze and explore the correlation between the changes in the gut microbiota and cardiovascular indexes caused by Flexi-Bar exercise.Results:（1）The body composition test results after 8-week Flexi bar exercise intervention showed that the body fat,body fat rate,waist circumference,hip circumference,right arm circumference and left thigh circumference in the control group before an d after the intervention were significantly increased（P < 0.05）,muscle mass,fat-free body mass,skeletal muscle,and fat-free mass of left and right legs decreased significantly（P < 0.05）.Compared with the exercise group before and after the intervention,body weight,hip circumference and left and right thigh circumference increased significantly after intervention（P < 0.05）,but no significant differences were found in body fat,muscle mass,lean body mass,skeletal muscle,body fat percentage and b ody mass index（BMI）（P > 0.05）;There were no significant differences between groups in body weight,body fat,muscle mass,lean body mass,skeletal muscle,BMI,body fat percentage and body dimension after intervention（P > 0.05）.Significant decrease（P < 0.05）.（2）The results of the cardiovascular function test af ter 8-week Flexi bar exercise intervention showed that there was no significant difference in cardiovascular indexes in the control group before and after the intervention（P > 0.05）.Compared with the control group,the right ankle-brachial artery pulse wave velocity（ba PWV）was significantly decreased（P < 0.05）,and FMD was significantly increased in the exe rcise group（P< 0.001）.（3）The results of serum factor concentrations after 8-week Flexi bar exercise intervention showed that there was no significant difference in the concentrations of e NOS,VEGF,VCAM-1 and TNF-α in the control group before and after the intervention（P > 0.05）,but the concentrations of ICAM-1 after the intervention compared with the control group,the TNF-α concentration in the exercise group decreased significantly after the intervention（P < 0.05）.（4）The results of 16 S r RNA sequencing and short-chain fatty acid detection after 8-week Flexi bar exercise showed that t here was no significant difference between the intra-and inter-group comparisons in αdiversity analysis（P > 0.05）.Compared with the control group,the abundance of Bacilli at the class level in the motor group increased significantly（P < 0.05）;the abundance of Butyricicoccaceae and Ruminococcaceae at the family level increased significantly（P < 0.05）;the abundance of Lachnospiraceae UCG-004 and Flavonifractor at the genus level decreased significantly（P < 0.05）,the abundance of Subdoligranulum increased significantly（P < 0.05）;compared with the short-chain fatty acid group,no significant difference was found in the control group（P > 0.05）,and the content of pro pionic acid and butyric acid in the exercise group decreased significantly after int ervention（P <0.05）;compared with the control group,the content of propionic acid and butyric acid in the exercise group was significantly decreased after the intervention（P < 0.05）.（5）The results of correlation analysis after 8 weeks of Flexi bar exercise showed that the c hange of ba PWV on the right side was significantly negatively correlated with the change of Bacilli bacteria（P <0.05）;the change of FMD was significantly negative ly correlated with the change of Lachnospiraceae UCG-004 bacteria Correlation（P < 0.05）;FMD was negatively correlated with TNF-α levels（P < 0.05）;Subdoligranulum changes were negatively correlated with changes in TNF-α levels（P < 0.05）.Clusion:（1）8-week Flexi-Bar exercise intervention can significantly improve the population composition a nd cardiovascular function of seden tary middle-aged and elderly women,and affect the abundance of gut microbiota.（2）8-week Flexi-Bar exercis e may improve vascular endothelial function and arte rial stiffness by changing the leve l of serum inflammatory factor TNF-α.（3）8-week Flexi-bar exercise may improve vascular function by changing the abundanc e of Bacilli bacteria at the gut microbiota level,Butyricicoccaceae,Ruminococcaceae bacteria abundance at the family level and Lachnospiraceae UCG-004,Flavonifractor,Subdoligranulum bacteria abundance at the genus level,thus affecting the release of metabolites short-chain fatty acids（propionic acid,butyric acid）. |
