A blood pressure reading gives you a picture of the force your blood flow is placing on your arterial walls. It is represented by two numbers. The top number of a blood pressure reading is the systolic pressure which is the force of your blood during a contraction. The bottom number is the diastolic reading and tells you the force of blood while your heart is filling. Diastolic pressure should be kept at 80 millimeters of mercury or less. During exercise, your diastolic pressure should not rise.
Response to Exercise
During exercise diastolic pressure changes very little. A normal and healthy response of your diastolic pressure during exercise is either no change or a slight reduction. Diastolic pressure should reduce by about 4 mmHg or less. This is a result of the dilation of your vessels necessary for increase blood flow to working muscles during exercise.
Abnormal Response
An increase of diastolic pressure greater than 15 mmHg is considered abnormal. An increase in diastolic pressure can be caused by arterial disease. If you notice an increase in diastolic pressure of this amount, stop your exercise program and see your doctor.
Isometric Exercise
During isometric exercise, your diastolic pressure responds differently during isometric exercise than traditional exercise. Isometric exercise is the production of force by your muscles without the use of movement. During this kind of contraction, your blood vessels become severely constricted. This vasoconstriction increases your diastolic pressure during exercise. However, once the contraction is over, your diastolic pressure should come back down.
Chronic Adaptations
While the diastolic response to exercise will not change, regular exercise can alter your resting diastolic pressure. The stimulus of exercise training causes the heart and cardiovascular system to become more efficient and better functioning. Part of this adaptation is a reduction in blood pressure, both diastolic and systolic. Exercise for just 30 to 45 minutes at a light to moderate intensity most days of the week.
