Certified Cardiographic Technician (CCT) Practice Exam 2025 - Free CCT Practice Questions and Study Guide

Cardiac output refers to the amount of blood the heart pumps in a given period, typically measured in liters per minute. During exercise, the body requires more oxygen and nutrients, which leads to an increase in cardiac output. This increase primarily results from two key factors: heart rate and stroke volume.

Heart rate, the number of times the heart beats per minute, typically increases during exercise to pump more blood. Stroke volume, the volume of blood pumped from the left ventricle with each contraction, can also increase due to improved ventricular filling and enhanced contractility driven by physical activity. Together, these two components significantly elevate cardiac output to meet the heightened demands of the body's tissues during exercise.

In contrast, the other options do not adequately address the primary mechanisms through which cardiac output increases during physical activity. Pulmonary and systemic vascular resistances relate more closely to blood flow regulation and pressure changes rather than direct contributions to cardiac output at rest or during exercise. Systolic and diastolic blood pressures are important for understanding overall cardiovascular health but do not directly define cardiac output. End diastolic and end systolic volumes deal with the filling and emptying capacities of the heart during its cycle but are not the primary indicators driving increased output during exercise. Thus,