Regular physical exercise is known to reduce cardiovascular risk. We examin
ed the effects of a single bout of moderate bicycle exercise on hemodynamic
measures at rest and in response to the foot cold pressor (CP) and mental
arithmetic (MA). Sedentary males and females (N = 32) were rested twice, fo
llowing 20 minutes of moderate exercise (exercise day) versus 20 minutes of
quiet rest (control day), Although resting blood pressure nas no lower 20
minutes after exercise relative to the same time point on the control dal:
diastolic blood pressure responses to CP (p =.05) and MA (p =.06) were atte
nuated on the exercise dal: Furthermore, recovery from moderate exercise ve
rsus control rest was also associated with reduced vascular resistance inde
x (VRI) at rest and during exposure to both stressors (p's less than or equ
al to.02). VRI reductions were largest in subjects with elevated vascular t
one on the control day and were accompanied by increases ill heart rate thr
oughout the postexercise period (p's less than or equal to.004) and higher
cardiac index during exercise recovery and in response to CP (p's less than
or equal to.05). Thus, the cardiovascular benefit of exercise may in part
be due to reduced VRI and attenuated cardiovascular responses to stress dur
ing the acute postexercise period.