Impact Of Combined Training With Different Exercise Intensities On Cardiovascular Function And Risk Factors In Patients With Type 2 Diabetes Mellitus

Objective:The prevalence of diabetes and related metabolic diseases has become a major global public health problem.The damage and dysfunction of cardiovascular system caused by long-term hyperglycemia and metabolic disorder are the key problems in diabetes prevention and control.Exercise is important in the management of type 2diabetes mellitus.Exercise,when performed on a regular basis,is a well-accepted strategy to improve cardiovascular function in patients with type 2 diabetes.However,the exercise intensity that yields maximal adaptations on structural and functional indices in patients with type 2 diabetes remains uncertain.This study therefore aimed to define the effect of high-intensity interval training combined with resistance training and moderate-intensity continuous training combined with resistance training on cardiovascular function and risk factors in patients with type 2 diabetes.Methods:54 patients who met the inclusion criteria were recruited from April to September2021 and randomly assigned to the HIIT+RT group（high-intensity interval training combined with resistance training）,MICT+RT group（moderate-intensity continuous training combined with resistance training）,and CG（control group）.With 18participants in each group,for 12 weeks,three times per week exercise intervention.CG group kept routine treatment,original living habits,and eating habits,and no exercise intervention;HIIT+RT group received 30 minutes of high-intensity interval training（4×4 minutes of high-intensity 80～95%HRmax separated by 3 minutes of low-intensity<50%HRmax recovery）,plus 30-minutes elastic band resistance training.MICT+RT group received 30 minutes of moderate-intensity 55～70%HRmax continuous training,plus 30-minutes elastic band resistance training.Before and after the experimental intervention,body composition measurement,cardiopulmonary exercise test,fasting venous blood test,atherosclerosis test and carotid artery,and heart ultrasound were performed.SPSS25.0 statistical software was used to statistically analyze the results of the interventions to observe the impact of high-intensity interval training combined with resistance training and moderate-intensity continuous training combined with resistance training on cardiovascular function and risk factors in patients with type 2 diabetes.Results:（1）After 12 weeks of intervention,HIIT+RT regimen and MICT+RT regimen significantly reduced body weight,body mass index,body fat mass,body fat percentage,and waist circumference in T2DM patients（P<0.01）.Compared with CG group,fat mass and body fat percentage of T2DM patients in HIIT+RT group and MICT+RT group were significantly decreased（P<0.05）.（2）After 12 weeks of intervention,HIIT+RT regimen significantly reduced Hb Ac1,FPG,TG,and LDL-c and TC in T2DM patients（P<0.01）;MICT+RT regimen significantly reduced Hb Ac1（P<0.05）,FPG（P<0.01）,TG（P<0.01）and LDL-c（P<0.01）in T2DM patients.Compared with CG group,HIIT+RT and MICT+RT regimen significantly reduced Hb Ac1（P<0.01）,FPG（P<0.01）and TG（P<0.05）in T2DM patients.There was no significant difference between HIIT+RT and MICT+RT.（3）After 12 weeks of intervention,HIIT+RT and MICT+RT significantly increased VO₂peak in T2DM patients（P<0.01）.Compared with CG,HIIT+RT and MICT+RT significantly increased the VO₂peak（P<0.01）.Compared with MICT+RT,HIIT+RT significantly increases the VO₂peak（5 m L/min/kg,P<0.01）.（4）After 12 weeks of intervention,HIIT+RT regimen significantly effect ba PWV（P<0.05）,ABI（P<0.01）,SBP（P<0.01）,DBP（P<0.01）,EF（P<0.01）,LVPWT（P<0.01）,LVEDD（P<0.01）and LVESD（P<0.01）and LVM（P<0.01）in T2DM patients.MICT+RT regimen had significant effects on ABI（P<0.01）,SBP（P<0.01）,DBP（P<0.01）,EF（P<0.01）,LVPW（P<0.01）,and LVM（P<0.05）in T2DM patients.Compared with CG,HIIT+RT regimen significantly effect SBP（P<0.01）,DBP（P<0.05）and EF（P<0.01）,LVEDD（P<0.01）,and LVM（P<0.05）in T2DM patients.MICT+RT decreased SBP（P<0.01）and DBP（P<0.05）.Compared with MICT+RT,HIIT+RT was more effective in improving LVEDD（P<0.05）.Conclusions:（1）12 weeks of high-intensity interval training combined with resistance training and moderate-intensity continuous training combined with resistance training significantly improved the risk factors of cardiovascular disease in T2DM patients,which would be beneficial to reduce the risk of cardiovascular disease in T2DM patients.（2）12 weeks of high-intensity interval training combined with resistance training and moderate-intensity continuous training combined with resistance training significantly improved peak oxygen uptake and cardiovascular structure and function in T2DM patients;However,high-intensity interval training combined with resistance training was more effective in improving cardiopulmonary fitness and cardiovascular structure and function in T2DM patients.