Blood pressure measures the force exerted by circulating blood against the walls of the body’s arteries. This measurement is given as two numbers: the top number, or systolic pressure, indicates the pressure when the heart beats and contracts to push blood out. The bottom number, or diastolic pressure, reflects the pressure in the arteries when the heart is resting between beats. Consistent running and aerobic exercise does not cause high blood pressure; instead, it is one of the most effective non-pharmaceutical methods for lowering resting blood pressure over time.
Running’s Long-Term Impact on Resting Blood Pressure
Consistent running strengthens the cardiovascular system, reducing the long-term pressure exerted on artery walls. Regular aerobic activity makes the heart muscle stronger and more efficient, allowing it to pump a greater volume of blood with fewer beats. This increased efficiency means the heart does not need to work as hard to maintain circulation, lessening the overall force on the blood vessels, which translates to lower resting blood pressure.
The benefits extend beyond the heart muscle itself, fundamentally changing the structure and function of the blood vessels. Regular training promotes vasodilation—the widening of the arteries and arterioles—reducing systemic vascular resistance. Running encourages the release of natural vasodilators, such as nitric oxide, which signals the smooth muscles in the vessel walls to relax and allow blood to flow more freely.
This chronic adaptation also improves arterial elasticity, reversing arterial stiffening that naturally occurs with age. Studies involving first-time marathon runners have shown that a structured training period can decrease aortic stiffness equivalent to a four-year reduction in vascular age. Overall, regular aerobic exercise lowers resting systolic blood pressure by four to ten millimeters of mercury (mm Hg) and diastolic pressure by five to eight mm Hg. For individuals already diagnosed with hypertension, the reduction can be even more pronounced, with average systolic drops approaching seven mm Hg.
Temporary Blood Pressure Changes During a Run
While running yields long-term benefits, the immediate physiological response during the activity is a temporary spike in blood pressure. As soon as a run begins, the working muscles demand significantly more oxygen and nutrients. To meet this demand, the heart pumps faster and harder, increasing its cardiac output and pushing a larger volume of blood through the circulatory system.
This increased force on the blood vessel walls causes a significant rise in systolic pressure, the top number. Conversely, the diastolic pressure, which measures the pressure between heartbeats, typically remains stable or only slightly increases during aerobic exercise. This temporary rise in systolic pressure is a normal response to physical exertion and is not a cause for concern in healthy individuals.
Immediately after the run ends, post-exercise hypotension (PEH) occurs, causing blood pressure to temporarily drop below pre-exercise levels. This reduction is caused by a sustained decrease in systemic vascular resistance and a resetting of the body’s blood pressure regulatory system. The magnitude and duration of this post-exercise drop are often greater in people who have hypertension, making a single bout of exercise an effective short-term intervention.
Why Some Runners Still Develop Hypertension
Despite the protective effects of running, the habit does not grant immunity from developing high blood pressure. Hypertension is a complex condition influenced by factors that can override the cardiovascular benefits of regular exercise. Genetics play a significant role, meaning individuals with a strong family history of high blood pressure may still develop the condition even with a rigorous running schedule.
Lifestyle choices outside of training can compromise a runner’s blood pressure control. A diet high in sodium, low in potassium, or excessive alcohol consumption can contribute to elevated pressure, counteracting the positive effects of running. Chronic psychological stress, poor sleep quality, and underlying medical conditions like kidney disease or diabetes are independent risk factors for hypertension.
In some cases, runners may exhibit exercise-induced hypertension (EIH), where blood pressure spikes to abnormally high levels during activity. This exaggerated response, sometimes defined as a systolic pressure above 210 mm Hg for men or 190 mm Hg for women, may be an early warning sign for developing resting hypertension later. Therefore, even dedicated runners must monitor their blood pressure regularly and address non-exercise factors to ensure optimal cardiovascular health.