Diabetes mellitus is a family of disorders of carbohydrate metabolism.we studied two groups of subjects: normotensive diabetic patients (Group I) and non diabetic age and gender matched controls group (Group II). We excluded those with hypertension, dyslipidemia, peripheral or autonomic neuropathy, smokers or ex-smokers and patients with history of or complaining from peripheral vascular disease, coronary artery disease or chest problems.patients in group I exhibited impaired exercise capacity, achieved a lower percentage of their age predicted heart rate, used a lower proportion of their chronotropic reserve, and retained a higher heart rate, systolic and diastolic blood pressure recorded in the post exercise period.There was a significant positive correlation between the mean carotid IMT and age, diastolic blood pressure at rest, peak of exercise and during the recovery period, and a significant negative correlation with exercise duration and METs achieved in the whole population.In diabetics there was a significant positive correlation between the mean carotid IMT and BMI, W/H ratio, resting HR, SBP at rest, peak of exercise and during recovery, FBS, total and LDL-cholesterol. Also, a significant negative correlation was found with HR attained at peak of exercise and the percentage achieved of the age predicted HR.The multivariate independent predictors for a higher carotid IMT in the diabetic group were longer diabetes duration, lower metabolic equivalent, higher FBS, older age and higher body mass index whereas in the control group only older age, higher body mass index and lower metabolic equivalent were the predictors for a higher carotid IMT.