16.5M at risk of stroke from exercising too hard: study

Push it — but not too hard.

Nearly 16.5 million Americans are at risk of stroke from exercising too hard, a new study found.

Published in the scientific journal Physics of Fluid, researchers concluded that an elevated heart rate can induce a stroke in those with blocked carotid arteries.

Carotid arteries are located on both sides of the neck and provide blood flow to the face and the brain.

But when fat and cholesterol build up, they form a plaque that narrows the artery, a process called stenosis.

Stenosis can be very difficult to detect early on and is dangerous because it limits blood flow to the brain, which can lead to a stroke.

An estimated 16.5 million (5%) Americans are estimated to experience carotid artery stenosis, according to the Cleveland Clinic.

Those who smoke, are obese, live a sedentary lifestyle and have high blood pressure, high cholesterol or diabetes are more likely to suffer from carotid artery stenosis. It can also develop with age.

Researchers from the Indian Institute of Technology Kharagpur used a computational model to simulate blood flow in carotid arteries at three stages of stenosis: without blockage, with a mild 30% blockage and with a moderate 50% blockage.

They compared the effect of an exercise-induced heart rate at 140 beats per minute, which can be achieved by a brisk walk for some obese people, and resting heart rates of 67 and 100 bpm.

Healthy patients and those with only slightly blocked arteries appeared to have exercise be beneficial for maintaining healthy blood flow.

However, the results for those with moderate to severe blockage were concerning.

“Intense exercise shows adverse effects on patients with moderate or higher stenosis levels,” said author Somnath Roy.

“It substantially increases the shear stress at the stenosis zone, which may cause the stenosis to rupture. This ruptured plaque may then flow to the brain and its blood supply, causing ischemic stroke.”

Stroke is the No. 5 cause of death in the US, yet 80% are preventable, the American Stroke Association reports.

The researchers concluded that “while stressful exercises may be beneficial for improving the cardiac performance of healthy individuals, the same may bring in extremely adverse consequences at elevated heart rates on account of extensive physical activities for patients having extensive arterial blockages, if not performed in supervision of specialized experts.”

As heart disease is the leading cause of death among Americans, heart health is incredibly important and continuously studied.

Another recent study found that getting too much sleep can actually be damaging to one’s health, while another found that spending just 30 minutes talking on the phone a week is linked with higher blood pressure.