Blood exerts pressure throughout the vascular system. The pressure is greatest in the arteries, and it is this arterial blood pressure that is generally measured and used as an indicator of health. If you have undergone a stress test, one of the parameters measured is how your blood pressure responds to various stages of exercise. During exercise, medical professionals want to see an increase in your systolic pressure.
Components
Your blood pressure reading is composed of two pressures. The systolic blood pressure is the pressure of the blood on the arteries when the heart is contracting -- this is reported as the top number of your blood pressure reading. Most of the focus is placed on the systolic pressure, as it increases with age and disease. Your diastolic number, or bottom reading, is the pressure of the blood on the arterial walls while the heart is relaxed. The measurement is reported in millimeters of mercury, or mmHg. The American Heart Association classifies a blood pressure lower than 120/80 mmHg as normal.
Exercise Response
During exercise, the demand for oxygen within the muscles increases. To meet this demand, the heart beats faster and harder to get the oxygen-rich blood out to those working muscles, which in turn increases your blood pressure. The American College of Sports Medicine, or ACSM, notes that a normal blood pressure response to exercise is a rise in the systolic blood pressure while the diastolic stays the same or slightly decreases. A drop in your systolic pressure, or the failure of it rising, is considered an abnormal response to exercise. Ideally, your systolic pressure should increase in proportion to the intensity of your exercise. Similar to exercise heart rate, you may see a plateau of your systolic pressure during peak exercise performance.
Endpoints
The ACSM recommends terminating exercise if your systolic pressure reaches 250 mmHg, drops with exercise or fails to rise greater than 10 mmHg. In addition, stop the exercise if your diastolic pressure increases or goes above 115 mmHg.
Indications
If your blood pressure is extremely high, it could be due to the hardening of the arteries. When the arteries lose elasticity, the pressure exerted on them by blood is greater. Therefore, high blood pressure during exercise can indicate the presence of cardiovascular disease. In addition, an abnormal response can also be a sign of valvular heart disease, a weakened or enlarged heart, or serious abnormal heart rhythms.
After Exercise
After exercise, your systolic pressure should return to back to or lower than where it started. It tends to stay lower for several hours after exercise because the vessels are relaxed. You may even display a lower diastolic pressure after exercise.
Chronic Effects
Regular aerobic, or cardiovascular, exercise has long been known to reduce blood pressure. MayoClinic.com estimates that 30 minutes a day of aerobic activity can lower systolic blood pressure by 5 to 10 mmHg. If you have borderline high blood pressure, exercise may be a great way to reduce your blood pressure while avoiding prescription medications. Furthermore, if your blood pressure is in the normal range, regular exercise may prevent blood pressure from increasing with age.
Warning
Talk to your physician before starting any new exercise program, particularly if you've been sedentary for a while. Strength training is an essential part of any regular exercise program; however, your blood pressure will temporarily rise during weight training, so it is imperative that you discuss this with your physician.
References
- Mayo Clinic: Exercise Blood Pressure
- American Heart Association: Understanding Blood Pressure Readings
- "ACSM's Guidelines for Exercise Testing and Prescription"; Lippincott, Williams & Wilikins; 2010
