Effects Of 8-week Flexi-bar Exercise Intervention On Cardiovascular Function In Sedentary Middle-aged And Elderly Women

Objective:To explore the suitable exercise for sedentary middle-aged and elderly women and to reduce the incidence of cardiovascular events,this study was designed to determine the influence of eight weeks of flexi-bar exercise of cardiovascular function and possible mechanism in middle-aged and elderly women.At the same time,it provides experimental evidence and theoretical basis for aerobic exercise to improve the cardiovascular function of middle-aged and elderly sedentary women.Methods:Thirty-two sedentary middle-aged and elderly women came from Guangzhou Cadre Sanatorium.The average age of the volunteers was 56.62±5.45 years old.The volunteers were randomly divided into two groups: the control group(Con group,n =16)and the flexi-bar exercise group(FE group,n=16).For 8 weeks,flexi-bar exercise intervention was performed 3 times a week,60 minutes each time,and the target heart rate was controlled at 50%～60% of the maximum heart rate.Body composition test and cardiovascular function test were performed and serum samples were extracted before and after intervention.Blood factors related to vascular function were detected,microRNAs(miRNAs)with differential expression were screened by RNA-seq,and miRNAs with differential expression pathways related to vascular function were analyzed.Results:(1)The results of body composition tests show that,the FE group’s body weight,body fat,body mass index(BMI),body fat rate,chest circumference,waist circumference,hip circumference,left arm circumference,right arm circumference,left thigh circumference and right thigh circumference were significantly lower than those in the Con group.(P<0.05)(2)The results of cardiovascular function tests showed that,the flow mediated dilation(FMD)of flow-mediated vasodilation in the FE group was significantly higher than that in the Con group(P < 0.001),and the subendocardial viability rate(SEVR)in the exercise group was significantly lower than that in the control group(P < 0.05).(3)The results of serum factor experiment showed,the endothelial nitric oxide synthetase(e NOS)in the FE group increased significantly after the exercise intervention(P < 0.01).(5)Differential expression of miRNAs in the FE group and the Con group before and after intervention was analyzed,and 84 differentially expressed miRNAs were screened out,among which mi R-199b-5p and mi R-652-3p were known to be closely related to the regulation of vascular function.Differential expression of miRNA in the FE group before and after intervention was analyzed,and 7 differentially expressed miRNA were screened out.Differential expression of miRNAs in the Con group and the FE group after intervention,and 88 differentially expressed miRNAs were screened out,among which mi R-21-3p and mi R-29b-3p are known to be closely related to the regulation of vascular function.Conclusion:8 weeks of flexi-bar exercise intervention significantly improved body composition and vascular endothelial function in middle-aged and elderly sedentary women.The mechanism of the improvement of vascular endothelial function in middle-aged and elderly sedentary women by flexi-bar exercise may be through the regulation of miRNAs related to vascular function,such as mi R-199b-5p and mi R-21-3p,thereby upregulating e NOS level of vascular endothelial.