Your client reports that she drank a 20 oz. (590 mL) cup of coffee 20 minutes prior to her exercise session. How might this affect her heart rate and blood pressure responses?

Caffeine does not decrease blood pressure - its vasoconstrictive and positive inotropic effects raise blood pressure, not lower it.

Although caffeine raises blood pressure, it does not decrease heart rate - its stimulant and catecholamine-releasing properties elevate rather than reduce heart rate.

Caffeine blocks adenosine receptors in the central nervous system and peripheral tissues, increasing sympathetic nervous system outflow and triggering catecholamine release. This causes elevated blood pressure through vasoconstriction and increased cardiac output, and raises heart rate through direct chronotropic stimulation - both cardiovascular measures are elevated when caffeine is consumed approximately 20-30 minutes before exercise, which aligns with its typical absorption window.

Caffeine is a stimulant with well-established sympathomimetic properties; it increases both blood pressure and heart rate rather than suppressing either measure.