TWO WEEKLY SESSIONS OF COMBINED AEROBIC AND RESISTANCE EXERCISE ARE SUFFICIENT TO PROVIDE BENEFICIAL EFFECTS IN SUBJECTS WITH TYPE 2 DIABETES MELLITUS AND METABOLIC SYNDROME

This study was performed to establish whether only 2 sessions per week of combined aerobic and resistance exercise are enough to reduce glycated hemoglobin (HbA(1c) and to induce changes in skeletal muscle gene expression in Type 2 diabetes mellitus (DM2) subjects with metabolic syndrome. Eight DM2 subjects underwent a 1-yr exercise program consisting of 2 weekly sessions of 140 min that combined aerobic [at 55-70% of maximal oxygen uptake (VO(2max))] and resistance circuit training [at 60-80% of 1 repetition maximum (RM)]. The training significantly improved VO(2max) (from 33.5 +/- 3.8 ml/kg/min to 38.2 +/- 3.5 ml/kg/min, p=0.0085) and muscle strength (p<0.05). Changes over baseline were significant for HbA(1c), reduced by 0.45% (p=0.0084), fasting blood glucose (from 8.8 +/- 1.5 to 6.9 +/- 2.2 mmol/l, p=0.0132), waist circumference (from 98.9 +/- 4.8 to 95.9 +/- 4.6 cm, p=0.0054), body weight (from 87.5 +/- 10.7 to 85.7 +/- 10.1 kg, p=0.0375), systolic blood pressure (from 137 +/- 15 to 126 +/- 8 mmHg, p=0.0455), total cholesterol (from 220 +/- 24 to 184 +/- 13 mg/dl, p=0.0057), and LDL-cholesterol (from 150 +/- 16 to 105 +/- 15 mg/dl, p=0.0004). Mitochondrial DNA/nuclear DNA ratio at 6 and 12 months did not change. There was a significant increase of mRNA of peroxisome proliferator-activated receptor (PPAR)-gamma after 6 months of training (p=0.024); PPAR alpha mRNA levels were significantly increased at 6 (p=0.035) and 12 months (p=0.044). The mRNA quantification of other genes measured [mitochondrially encoded cytochrome c oxidase subunit II (MTCO2), cytochrome c oxidase subunit Vb (COX5b), PPAR gamma coactivator l alpha (PGC1 alpha), glucose transporter 4 (GLUT 4), forkhead transcription factor BOX O1 (FOXO-1), carnitine palmitoyltransferase 1 (CPT-1), lipoprotein lipase (LPL), and insulin receptor substrate 1 (IRS-1)] did not show significant changes at 6 and 12 months. This study suggests that a twice-per-week frequency of exercise is sufficient to improve glucose control and the expression of skeletal muscle PPAR gamma and PPAR alpha in DM2 subjects with metabolic syndrome.