1. systolic pressure increases when the degree of exercise increases
Systolic pressure increases gradually from 115 mmHg at rest to 150 mmHg during severe exercise. When thr degree of exercise increases, the skeleton muscle needs more energy(ATP) for rapid contraction by carrying out aerobic respiration. The skeleton muscle required faster uptake of oxygen and removal of carbon dioxide. At the same time, skeleton muscle carries our anaerobic respiration to provide addition amount of ATP for rapid contraction. Partially oxidized lactic acid is produced during anaerobic respiration which lowers the blood pH. When the chemoreceptors including carotid bodied and aortic bodies detect the decrease in pH, they send nerve impulses to stimulate the cardioacceleratory center which then stimulate the cardiac muscles to contract more strongly and more rapidly. As a result, pressure …show more content…
According to Frank-Starling Law, stroke volume increases as the end-diastolic volume increases. For this reason, the systolic pressure increases.
2. diastolic pressure remains relatively constant
Diastolic pressure remains 75mmHg at rest and during slight exercise. At the same time, diastolic pressure gradually drops from 75mmHg during slight exercise to 55 mmHg during severe exercise. Generally, diastolic pressure remains relatively constant when comparing with systolic pressure. Diastolic pressure is measured when both ventricles of heart relax and blood is refilling into the heart. As the volume of blood is fixed, the pressure created on arteries is nearly the same during diastole.
3. mean arterial pressure remain relatively constant
The mean arterial pressure increases from 88.333 mmHg at rest to 91.667 mmHg during slight