What typically happens to heart rate (HR) during an acute response to exercise?

During acute exercise, the body's demand for oxygen increases, which necessitates a rapid response from the cardiovascular system. As a result, heart rate increases significantly to pump more blood, and consequently, more oxygen, to the working muscles. This immediate response is crucial as it supports the heightened metabolic activity that occurs during physical exertion. The nervous system and hormonal responses trigger this increase, allowing the heart to respond quickly to the demands of exercise.

Following the initial increase, heart rate typically reaches a steady state if the exercise intensity remains constant, where it may plateau rather than decrease or remain unchanged. Thus, the understanding of heart rate dynamics during exercise is critical for assessing cardiovascular health and fitness levels.