Exercise is often called one of the best ways to stay healthy. It can help people control weight, improve heart health, lower stress, and reduce the risk of many diseases.
Doctors around the world encourage people to stay active because regular movement is usually good for the body and mind.
But a new study from the Indian Institute of Technology Kharagpur suggests that intense exercise may not always be safe for everyone. In some people, especially those with blocked arteries in the neck, hard exercise could increase the risk of stroke.
The research focused on the carotid arteries, which are two large blood vessels located on each side of the neck. These arteries play a very important role because they carry oxygen-rich blood from the heart to the brain and face.
The brain depends on a steady flow of blood to work properly. If blood flow is reduced or blocked, brain cells can quickly become damaged.
Over time, fatty material called plaque can build up inside these arteries. This buildup can slowly narrow the blood vessels and make it harder for blood to pass through. Doctors call this condition carotid artery stenosis.
The problem becomes more common as people age, especially in people with high blood pressure, diabetes, smoking habits, obesity, or high cholesterol. Sometimes people do not even know they have narrowed arteries because the condition may not cause clear symptoms until it becomes serious.
A stroke can happen when blood flow to part of the brain suddenly stops. This may occur because a blood clot blocks an artery or because plaque inside an artery breaks apart and travels into smaller blood vessels in the brain.
Strokes can cause permanent brain damage, speech problems, memory loss, weakness, or even death. Because of this, doctors are always searching for better ways to understand stroke risks and protect people before a dangerous event happens.
In the new study, the researchers used advanced computer models to study how blood moves through carotid arteries with different levels of blockage.
The scientists wanted to understand what happens inside these blood vessels when heart rate increases during exercise. The team compared healthy arteries with arteries that had mild, moderate, and severe narrowing.
The computer simulations showed that people with healthy arteries or only small amounts of blockage generally benefited from a faster heartbeat during exercise. As the heart pumped harder, blood continued to flow smoothly through the arteries.
The movement of blood against the artery walls created healthy pressure that may help reduce further plaque buildup. This finding supports the widely known benefits of regular exercise for most people.
However, the situation changed when the arteries were already moderately or severely narrowed. In these cases, intense exercise created very high stress on the walls of the arteries near the blocked areas.
Scientists describe this force as shear stress. Too much stress in these weakened areas may make plaque unstable. If plaque cracks or breaks away, it can move through the bloodstream into the brain and block blood flow. This could trigger a stroke.
The researchers also found another possible problem. Intense exercise in people with existing blockages may increase conditions that encourage more plaque to form over time. This means that the arteries could continue to narrow in the future if the underlying condition is not treated properly.
The study does not mean that exercise is dangerous for everyone. In fact, physical activity remains one of the most important ways to protect overall health.
Exercise can lower blood pressure, improve circulation, strengthen the heart, and reduce the risk of many diseases. But the study highlights an important message: not all exercise plans are suitable for every person.
The researchers believe that older adults and people with known risk factors for heart disease or stroke should pay closer attention to the health of their carotid arteries before starting very intense exercise programs.
Risk factors include smoking, diabetes, high cholesterol, obesity, and a family history of heart disease. A simple medical scan can often detect dangerous narrowing in the arteries before symptoms appear.
For people who already have moderate or severe artery narrowing, doctors may recommend safer forms of physical activity instead of high-intensity exercise.
Gentle activities such as walking, light cycling, stretching, or swimming may still provide important health benefits without placing too much stress on the arteries. Medical supervision can help people stay active while reducing unnecessary risks.
The findings also remind people that health advice is not always one-size-fits-all. Two people may exercise in very different ways depending on their age, medical history, and physical condition.
What is safe for one person may not be safe for another. Personalized medical care and regular checkups can help people make better decisions about exercise and long-term health.
The study was published in the scientific journal Physics in Fluids. The research adds to growing efforts by scientists around the world to better understand how exercise, blood flow, and artery disease interact. By learning more about these hidden risks, doctors may one day develop safer exercise guidelines for people who are at higher risk of stroke.
If you care about stroke, please read studies that diets high in flavonoids could help reduce stroke risk, and MIND diet could slow down cognitive decline after stroke.
For more health information, please see recent studies about antioxidants that could help reduce the risk of dementia, and tea and coffee may help lower your risk of stroke, dementia.
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