Key Words: Exercise, hemorheological parameters, smokers

Aim: Regular physical exercise is associated with reduced risk of cardiovascular diseases. In this study, the hypothesis that acute submaximal exercise has similar effects on rheological parameters of smokers and non-smokers was tested. Materials and Methods: Thirty-three male university undergraduates comprised of 18 smokers and 15 non-smokers were studied. All the subjects underwent submaximal exercise on cycloergometer for 30 minutes. Blood for hemorheological parameters was collected 30 minutes before and after exercise. Samples were analyzed by standard methods. Results: A total of 33 undergraduates were studied. The hematocrit, plasma viscosity and plasma fibrinogen were significantly higher in smokers than non-smokers (P < 0.01). Post- exercise plasma viscosity was significantly higher than pre-exercise value in non-smokers (P < 0.0001). Hematocrit, plasma viscosity and plasma fibrinogen were also significantly higher post-exercise in smokers (P < 0.01, P < 0.01 and P < 0.05, respectively). The white cell count and whole blood viscosity were 17.8 % and 9 % higher, respectively, than pre-exercise values in smokers. Conclusions: The study confirmed an acute rise in rheological parameters in smokers and non-smokers following submaximal exercise; however, smokers are more liable to cardiovascular effects of acute intense exercise, especially those with sedentary lifestyle