The stiffening of arteries is associated with various cardiovascular diseases. Arterial stiffening can be studied utilizing arterial pulse wave velocity (PWV), but the absence of reliable reference values for PWV has limited its use in clinical practice. The aim of this study was to establish a range of reference values for PWV. PWV was examined by measuring the time difference of systolic pulse waves in arteries from the aortic arch to the popliteal artery using whole-body impedance cardiography (ICG). The study population consisted of 799 individuals (age range 25-76 years), 283 of whom had no evidence of cardiovascular disease, and a low burden of risk factors was selected to represent an apparently healthy population. In healthy study population, PWV was higher in males (8 x 9 +/- 1 x 8 m s(-1)) than females (8 x 1 +/- 2 x 0 m s(-1), P<0 x 001). Young males had lower PWV values than old males. Correspondingly, young females also had lower PWV values than old females. PWV was clearly associated with age, and PWV was higher in young and middle-aged males than in females. There was no statistically significant difference between old males and females in PWV. In conclusion, whole-body ICG provides a practical method for PWV measurement. Reference values can be useful in the clinical management of patients, especially in detecting early vascular disease or an increased risk of cardiovascular complications.