Diastolic blood pressure is the force of your blood pushing through your arteries while the heart is resting between beats. It is represented by the lower of the two numbers in your blood pressure reading. The normal diastolic blood pressure during exercise should be unchanged, or there may be a slight lowering or an increase of no more than 10 mmHg. Any increase above this value indicates the presence of an unstable type of hypertension, which may be a sign of disease.
Diastolic Hypertension and Diabetes
The journal "Circulation" presented a study by Sally Brett in 2000 where healthy and diabetic men engaged in moderate aerobic exercise and their blood pressure and response to insulin measured. It was observed that diastolic blood pressure in healthy men remained fairly constant throughout. There was a positive correlation between increased diastolic pressure and insulin resistance in test subjects. The implication from these results is that diastolic hypertension during exercise may be an indication of an underlying medical problem such as Type 2 diabetes.
Diastolic Hypertension and Cholesterol
A 2008 study published in the "Journal of Cardiopulmonary Rehabilitation and Prevention" examined 275 subjects with no previous hypertensive diagnosis. Of this number, 35 individuals responded to exercise with increased diastolic pressure measuring greater than or equal to 90 mmHg. These individuals were paired with a control group that did not show diastolic hypertension during exercise. Further testing revealed that the test subjects had significantly higher cholesterol levels than the control group.
Diastolic Hypertension May Not Indicate Coronary Artery Disease
The association of diastolic hypertension in response to exercise has been considered a possible predictor of coronary artery disease. The "European Heart Journal" published a study where researchers attempted to assess the predictive value of exercise induced diastolic hypertension. The researchers had 111 subjects with coronary artery disease and 53 normal subjects use an exercise bike and recorded the variations in diastolic blood pressure. It was found that diastolic hypertension had 55 percent accuracy as a predictive tool for coronary artery disease, suggesting that, while an abnormal response in diastolic blood pressure during exercise may sometimes result from coronary artery disease, other factors may be equally responsible.
Consideration
Your diastolic blood pressure is determined by the volume of blood your heart pumps out and the resistance of the blood vessels. When you exercise, your heart pumps more blood and your blood vessels become less resistant, allowing them to dilate. This increase in size accommodates the higher blood volume and keeps your diastolic pressure from increasing too much. Any condition that causes an unusually high cardiac output or decreases the ability of blood vessels to dilate will lead to diastolic hypertension during exercise. A thorough medical examination can determine the cause of your exercise related diastolic hypertension.
References
- University of Maryland Medical Center: Exercise and Resting Blood Pressure
- "Circulation": Diastolic Blood Pressure Changes During Exercise; S. Brett; 2000
- "Journal of Cardiopulmonary Rehabilitation and Prevention": Diastolic Pressure; R. Arena; Jan 2008
- "European Heart Journal": Exercise Induced Diastolic Hypertension; D. Acanfora; 1999
