Your normal blood pressure is 120/80 millimeters of mercury, mmHg, at rest. The 120 is the systolic pressure-pulse your heart generates to drive blood through your arteries. The 80 is the diastolic pressure it drops to between beats. Exercise makes your heart beat harder and faster to produce higher systolic pressure to push more blood to your muscles and relaxes your arteries to ease flow and keep diastolic pressure low so the next beat meets little resistance.
Normal Variability
Normal blood pressure varies widely with changes in your activity. Though some exercise-induced changes vary with age, exercise always raises blood pressure within safe limits in healthy individuals, according to a 2010 report published in the "Journal of Applied Physiology" by a research team at the School of Sport and Exercise Sciences, University of Birmingham, UK. However, poorly executed exercise can send it too high. Doug Jones, founder and host of The Best Way To Exercise website, demonstrates on a 2009 YouTube video proper exercise breathing to prevent dangerous blood pressure spikes. Exhale on exertion when you lift and inhale when you let a weight down. A closed glottis while straining to build up pressure in your lungs during exercise might double or triple your blood pressure and cause fainting or even strokes.
Systolic Pressure
Mayo Clinic researchers reviewed treadmill exercise test records of 7,863 healthy males and 2,406 females. Results, published in a 1995 report in the Mayo Clinic Proceedings, documented that peak systolic pressures at maximum exercise were higher in men than women and rose with advancing age. In men, 20- to 29-years-old, peak systolic blood pressure of 210 mm Hg rose to 234 mm Hg at age 70 to 79 years. In women, peak exercise systolic pressure rose from 180 mm Hg to 220 mm Hg between those age ranges.
Diastolic Pressure
According to Len Kravits, Ph.D., of the University of New Mexico Department of Exercise Physiology, exercise may cause only a mild increase in diastolic pressure or even a slight decrease. Vasodilation, a relaxation and widening of arteries during exercise, is responsible for the lower diastolic blood pressure. A diastolic increase of more than 10 mmHg during exercise or recovery is abnormal -- an unstable form of hypertension -- and may indicate coronary artery disease.
Delta Pressure
The delta pressure is the difference between your resting blood pressure and your peak exercise blood pressure. The Mayo Clinic study showed that after the 40 to 49 year age decade the delta pressure normally became smaller. This means that older, healthy subjects had a somewhat milder blood pressure response to exercise than younger subjects. This was related to a heightened protective reflex in older subjects against blood pressure spikes and a weaker protection against drops in blood pressure.
Return to Normal
The normal blood pressure reaction when exercising may be therapeutic, says Kravitz. Moderately intense aerobic exercise -- workouts that raise your oxygen consumption to 40 to 60 percent of maximum for 30 to 45 minutes, four or more days a week -- can treat mild hypertension. Within the first few weeks of starting an exercise program, resting systolic and diastolic blood pressure may drop back towards normal by eight to 10 mmHg and six to 10 mmHg, respectively.
References
- Mayo Clinic: Peak Exercise Blood Pressure Stratified by Age and Gender in Apparently Healthy Subjects
- YouTube: The Best Way to Lower Blood Pressure During Exercise
- University of New Mexico: Exercise and Resting Blood Pressure
- American Journal of Physiology: Control of Blood Pressure at Rest and During Exercise
