Blood pressure is a good indicator of cardiovascular health. The top number, or systolic blood pressure, represents the force on the arteries when the heart beats. The bottom number, or diastolic blood pressure, represents the force on the artieries when the heart is at rest. Both numbers have different responses to exercise.
Diastolic Blood Presure and Aerobic Exercise
Diastolic blood pressure should remain the same or slightly decrease during exercise. Dr. Len Kravitz of the University of New Mexico notes that the decrease in diastolic blood pressure is due to the vasodilation, or increased size, of the blood vessels. The actual number during exercise will depend on your number at rest. For example, if your resting blood pressure is 120/80 mmHg, your diastolic blood pressure during exercise should be at or slightly less than 80 mmHg.
Abnormal Diastolic Blood Pressure Response
Heavy resistance training and isometric exercises, like an arm hang, can produce dramatic increases in diastolic blood pressure. A study in the "Journal of Applied Physiology" demonstrated that a portion of this increase is due to breath holding and the Valsalva maneuver. Light resistance training and circuit training has little effect on diastolic blood pressure. Proper breathing techniques can help minimize increases in diastolic blood pressure during resistance training.
Abnormal Diastolic Blood Pressure Response
If your diastolic blood pressure raises more than 10 mmHg during exercise, stop immediately and address it with your doctor. This is abnormal, a form of unstable hypertension, and may indicate coronary artery disease.
Before You Start
The American College of Sports Medicine identifies a resting blood pressure equal or greater than 200/100 mmHg as a contraindication to exercise. Talk to your doctor before beginning an exercise if you have hypertension.
References
- University of New Mexico: Exercise and Resting Blood Pressure; Len Kravitz, PhD; 2001
- "Guidelines for Exercise Testing and Prescription"; American College of Sports Medicine; 2010
- "Journal of Applied Physiology"; Arterial Blood Pressure Response to Heavy Resistance Exercise; J.D. MacDougall, et al., 1985
