The physiological changes occurring during exercise and its possible conseq
uences have been receiving considerable attention lately. In this paper, we
studied the changes in hemorheological and microcirculatory parameters, be
fore and after the exercise, in the subjects undergoing mild exercise (n =
20). A cycle ergometer adjusted at 2.5 kilopounds was used for 15 minutes.
The whole blood viscosity showed a significant increase after exercise at a
ll shear rates (0.512-51.2/s) except at the high shear rate (94.5/s). Howev
er, the significant level was more (P < 0.005) at low shear rates (0.512-4.
39/s). A significant elevation in plasma viscosity was observed after the e
xercise (P < 0.0008). Red cell rigidity showed a significant increase after
the exercise (P < 0.001) while red cell aggregation and hematocrit failed
to show any significant change. Microcirculatory studies showed a significa
nt increase in the basal perfusion level after exercise (P < 0.0002) when c
ompared to the resting state value. There was a significant decrease in rea
ctive hyperaemia perfusion index after exercise (P < 0.0007). Hence, it is
evident from this study that short-term exercise significantly alters hemor
heological and microcirculatory parameters.