Patient Care Technician (PCT) AAH Practice Exam

Which vital sign is affected by both metabolic rate and physical activity?

1. Blood pressure

2. Temperature

3. Pulse

4. Respiration

The correct answer is: Pulse

The pulse is the vital sign that is directly influenced by both metabolic rate and physical activity. Metabolic rate refers to the speed at which the body converts food into energy, and when the metabolic rate increases—such as during exercise or physical activity—the body requires more oxygen and nutrients, which results in an increased heart rate to supply the necessary resources to the tissues. This elevated heart rate is reflected in a higher pulse rate. Additionally, during physical activity, the muscles require more oxygen to sustain efforts, prompting the heart to pump faster. Therefore, the pulse effectively indicates the body’s response to both elevated metabolic demands and the intensity of physical exertion. While blood pressure can be influenced by physical activity, it is not as directly tied to metabolic rate in the same way the pulse is. Temperature can indicate metabolic activity but is less responsive to immediate changes from physical activity. Respiration rates can also rise with physical activity; however, they are primarily regulated by the need for oxygen and the removal of carbon dioxide rather than metabolic rate alone. Therefore, pulse is the most directly impacted by both factors.