Effects of Aerobic Exercise vs. Resistance Training on Endothelial Function in Women with Type 2 Diabetes Mellitus

BACKGROUND: There is controversy over whether aerobic or resistance exercise is more effective for improving endothelial function in type 2 diabetes mellitus (T2DM). This study was aimed to investigate the effects of an aerobic and resistance training program on endothelial function, and the influences of glycemic control, body weight changes, and aerobic capacity in T2DM. METHODS: Total 40 overweight women with T2DM were assigned into 3 groups: an aerobic exercise group (AEG, n=13), resistance exercise group (REG, n=12), and control group (CG, n=15), and followed either brisk walking for the AEG or resistance band training for the REG, 60 minutes per day, 5 days per week for 12 weeks with monitoring daily activity using accelerometers. We assessed endothelial function by flow-mediated dilation (FMD), and aerobic capacity by oxygen uptake at anaerobic threshold (AT_VO2) at baseline and following training program. RESULTS: The mean participants' age was 57.0+/-6.8 years, and body mass index (BMI) was 27.0+/-2.3 kg/m2. After intervention, FMD increased by 2.2+/-1.9% in AEG, which differed from REG and CG (P=0.002), despite of decreased body weight (BW) in both AG and RG (2.8+/-2.5%, P=0.002; 1.6+/-2.0%, P=0.017, respectively). A significant increased AT_VO2 and decreased HbA1c were found only in AEG. In all participants, FMD was changed with the significant relations to the AT_VO2 (r=0.348, P=0.035), but not to HbA1c levels or BW. CONCLUSION: Aerobic exercise appears to be more beneficial than resistance exercise for improving endothelial function in T2DM. In addition, aerobic capacity could be a better predictor of changes in FMD than BW and glycemic control.

Effects of Aerobic Exercise on Abdominal Fat, Thigh Muscle Mass and Muscle Strength in Type 2 Diabetic Subject / 당뇨병

BACKGROUND: Aerobic exercise can effectively reduce visceral fat. However, few studies have examined the effect of daily physical activity on obesity and cardiopulmonary function in the subjects with diabetes. We examined the effect of moderate intensity of walking in obese diabetes patients by monitoring of daily activity and measuring the change in abdominal fat area, muscle are and maximal muscle strength. METHODS: We randomly assigned 27 obese women with type 2 diabetes to an aerobic exercise group (AG, n = 13) and control group (CG, n = 14). The AG performed moderate intensity walking for 60 minutes per exercise, 5 times per week, and for 12 weeks. The activity energy expenditure was monitored by a multi-record accelerometer. The CG maintained routine daily activities. At the time of the initiation of the study and after 12 weeks of exercise, the aerobic exercise capacity was assessed using oxygen consumption rate at anaerobic threshold (VO2-AT). The abdominal fat area and the quadriceps muscle area were measured by computed tomography, and the maximum muscle strength of the upper and lower limbs was measured by a chest press and a leg press, respectively. RESULTS: The mean age of the study subjects was 56.6 +/- 8.0 years, the mean duration of diabetes was 6.3 +/- 6.0 years, and the body weight index (BMI) was 27.3 +/- 2.7 kg/m2. The BMI of the AG was significantly decreased (P = 0.003). In the AG, the visceral fat area and subcutaneous fat area were also significantly decreased (P = 0.018 and P < 0.001, respectively) but not in CG. VO2-AT of the AG was significantly improved, while that of the CG did not change (P = 0.009 and P = 0.115, respectively). The quadriceps muscle mass and the maximal muscle strength of the AG did not change, however, the CG showed a significant decrease. Duration of moderate intensity exercise was correlated with the decrease in total abdominal fat area (r = -0.484; P = 0.011) and that of high intensity exercise was correlated with improvement of cardiopulmonary function (r = 0.414; P = 0.032). CONCLUSION: Daily moderate intensity aerobic exercise is effective at reducing abdominal fat mass, while high intensity exercise improves cardiopulmonary function.

Effects of Aerobic Exercise on Abdominal Fat, Thigh Muscle Mass and Muscle Strength in Type 2 Diabetic Subject / 당뇨병

BACKGROUND: Aerobic exercise can effectively reduce visceral fat. However, few studies have examined the effect of daily physical activity on obesity and cardiopulmonary function in the subjects with diabetes. We examined the effect of moderate intensity of walking in obese diabetes patients by monitoring of daily activity and measuring the change in abdominal fat area, muscle are and maximal muscle strength. METHODS: We randomly assigned 27 obese women with type 2 diabetes to an aerobic exercise group (AG, n = 13) and control group (CG, n = 14). The AG performed moderate intensity walking for 60 minutes per exercise, 5 times per week, and for 12 weeks. The activity energy expenditure was monitored by a multi-record accelerometer. The CG maintained routine daily activities. At the time of the initiation of the study and after 12 weeks of exercise, the aerobic exercise capacity was assessed using oxygen consumption rate at anaerobic threshold (VO2-AT). The abdominal fat area and the quadriceps muscle area were measured by computed tomography, and the maximum muscle strength of the upper and lower limbs was measured by a chest press and a leg press, respectively. RESULTS: The mean age of the study subjects was 56.6 +/- 8.0 years, the mean duration of diabetes was 6.3 +/- 6.0 years, and the body weight index (BMI) was 27.3 +/- 2.7 kg/m2. The BMI of the AG was significantly decreased (P = 0.003). In the AG, the visceral fat area and subcutaneous fat area were also significantly decreased (P = 0.018 and P < 0.001, respectively) but not in CG. VO2-AT of the AG was significantly improved, while that of the CG did not change (P = 0.009 and P = 0.115, respectively). The quadriceps muscle mass and the maximal muscle strength of the AG did not change, however, the CG showed a significant decrease. Duration of moderate intensity exercise was correlated with the decrease in total abdominal fat area (r = -0.484; P = 0.011) and that of high intensity exercise was correlated with improvement of cardiopulmonary function (r = 0.414; P = 0.032). CONCLUSION: Daily moderate intensity aerobic exercise is effective at reducing abdominal fat mass, while high intensity exercise improves cardiopulmonary function.

Effects of Aerobic Exercise Intensity on Insulin Resistance in Patients with Type 2 Diabetes Mellitus / 당뇨병

BACKGROUND: Exercise offers protection against atherosclerosis and insulin resistance. We evaluated the benefits of exercise at different levels of intensity for ameliorating inflammation, endothelial dysfunction, and insulin resistance in a sample of type 2 diabetic subjects. METHODS: Fifty-nine overweight women with type 2 diabetes were randomly assigned to control (CG, N = 18), moderate-intensity exercise (MEG, N = 17), and vigorous-intensity exercise (VEG, N = 14) groups. Patients in the two experimental groups completed a 12-week exercise program, with their exercise activities monitored by accelerometers. We assessed the patients' body weights, total abdominal fat (TF), subcutaneous fat (SF) and visceral fat (VF) via computed tomography, measurements of plasma levels of hs-C-reactive protein (hs-CRP) and interleukin-6 (IL-6), assessment of endothelial function by brachial artery flow-mediated dilation (FMD), and evaluation of insulin sensitivity by insulin tolerance tests, at baseline, at the end of the 12-week interventions, and one year after initiation of the study. RESULTS: At baseline, the average age of all subjects was 54 +/- 7 years, and average body mass index (BMI) was 26.9 +/- 2.5 kg/m2. During the intervention, patients in the MEG and VEG groups expended comparable amounts of activity-related calories (488.6 +/- 111.9 kcal/day, 518.8 +/- 104.1 kcal/day, respectively). Although BMI, TF, and SF decreased similarly in the MEG and VEG groups (deltaBMI: -1.1 +/- 0.7, -0.8 +/- 0.5, deltaTF: -4,647 +/- 3,613 mm2, -2,577 +/- 2,872 mm2, deltaSF: -2,057 +/- 2,021 mm2, -1,141 +/- 1,825 mm2, respectively), compared to control (P<0.01), hs-CRP, IL-6, and FMD remained constant in both exercise groups even after completion of the 12-week exercise intervention. Insulin sensitivity improved only in patients subjected to vigorous exercise (VEG). Visceral fat loss was observed only in patients subjected to moderate exercise (MEG). At one-year follow up, these values had all returned to baseline. CONCLUSION: Exercise vigorous enough to result in significant weight and fat reduction did not ameliorate inflammation and endothelial dysfunction as measured at the end of a 12-week exercise intervention, nor did it result in sustained improvements in insulin sensitivity in type 2 diabetic subjects.