Improved carbohydrate metabolism after physical training and dietary intervention in individuals with the 'atherothrombogenic syndrome'. Oslo Diet and Exercise Study (ODES). A randomized trial

Objectives. To compare the single and joint effect of 1-year diet and exercise intervention on carbohydrate metabolism and associated coronary risk variables. Design. Unmasked, randomized, 2x2 factorial intervention trial with 1-year duration for each participant. Setting. The participants were recruited from a screening examination of 40-year-old persons in Oslo, Norway. Subjects. Two hundred and nineteen sedentary men and women, with diastolic blood pressure 86-99 mmHg, HDL cholesterol <1.20 mmol L(-1), triglycerides >1.4 mmol L(-1), total cholesterol 5.20-7.74 mmol L(-1) and BMI >24. Participants were randomly allocated to control (n=43), diet (n=55), exercise (n=54) and diet+exercise (n=67). Interventions. Exercise: supervised endurance exercise three times a week, Diet: reduce weight, increase the intake of fish and reduce total fat intake. Main outcome measures, One-year changes in insulin and glucose before and after a standardized glucose load. Results. As compared with controls fasting insulin in pmol L(-1) decreased significantly in the combined diet and exercise group (3.9+/-6.2 versus -22.6+/-4.7 respectively, P=0.003). Insulin in pmol L(-1) after glucose load decreased significantly in all intervention groups compared to controls (diet: -82.2+/-49.9 P=0.02; exercise: -92.4+/-60.1 P=0.03; diet+exercise: -179.6+/-45.1 P=0.0004). Fasting glucose in mmol L(-1) decreased significantly in the diet alone group (0.21+/-0.07 P=0.006) and in the diet+exercise group (-0.26+/-0.08 P=0.005). In a subgroup analysis of the good responders, the observed changes with respect to total cholesterol (-0.76 mmol L(-1)), HDL cholesterol (0.16 mmol L(-1)), triglycerides (-0.72 mmol L(-1)), systolic and diastolic blood pressure (-8.5/-6.8 mmHg) were all statistically significant compared to the control with P <0.001. Conclusions. Exercise and diet intervention and in particular the combination of the two, were effective in improving carbohydrate metabolism. Associated risk factors were also affected in a beneficial direction.