Low Blood pressure and exercise

Low blood pressure, also known as hypotension, is defined as blood pressure less than 90/60 mmHg. One serious consequence of low blood pressure includes lack of adequate blood flow to the brain, which may lead to episodes of dizziness or fainting. In some cases, exercise may lead to the problem of insufficient brain blood flow, thus producing dizziness.

Symptoms of Hypotension

When the blood pressure drops below 90/60, the brain is not being adequately perfused with blood. This leads to a problem supplying the brain with oxygen and nutrients, which are both carried by the blood. A lack of sufficient oxygen leads to serious damage to neurons, the cells of the brain. The early signs of insufficient brain blood flow include dizziness and fainting. This is your body’s way of correcting the problem: Since not enough blood is getting to the head, you are forced to fall down so blood can get where it needs to go.

Causes of Hypotension

Multiple cardiovascular abnormalities can lead to hypotension. If you are low on blood volume, either from dehydration, pregnancy or traumatic hemorrhage, the pressure within the vessels will decrease and could lead to perfusion difficulties. Alternatively, heart failure may lead to insufficient cardiac output, thus decreasing pressure due to a malfunctioning pump. Finally, an abnormality in pressure feedback mechanisms might lead to positional hypotension. In this case, the sensors in your brain that are designed to detect blood pressure are malfunctional. These feedback regulators are unable to communicate low-blood-pressure signals as they normally would.

Exercise-Induced Hypotension

If you experience fainting or dizzy spells during exercise, you may have exercise induced hypotension. The cause of the problem could be a weak heart that is unable to keep up with the demands you place on it during exercise. Alternatively, you may simply be dehydrated and low on blood volume.


Symptoms of dizziness or fainting are serious neurological problems and should be properly evaluated by your physician. Treatment for this condition varies depending on the root cause of hypotension. For instance, if proper hydration during exercise fixes the problem, then your hypotension was likely caused by dehydration. If the problem is a weak heart, you may be referred to a cardiologist for further evaluation.