During an acute stress reaction which physiological change is most likely?

• A. Increased heart rate
• B. Decreased heart rate
• C. Decreased respiration
• D. Slowed metabolism

Answer: (A)

Acute stress triggers the body’s fight-or-flight response, activating the sympathetic nervous system. This causes a surge of catecholamines (like adrenaline) that increases heart rate to boost cardiac output so oxygen and nutrients reach muscles quickly. That rapid heart pacing is a hallmark of the immediate reaction to stress and helps prepare the body for swift action. While respiration often increases too, the most consistent and direct change among these options is a faster heart rate. The other choices—slower heart rate, reduced breathing, or slowed metabolism—go against the body’s immediate need for rapid energy, oxygen delivery, and alertness during acute stress.