Often referred to as a "brain attack," strokes are serious medical conditions that occur when blood flow to a part of the brain is interrupted or reduced. Strokes can have significant consequences, including paralysis, cognitive impairment, and in some cases, even death. According to the World Health Organization (WHO), strokes are the second leading cause of death globally, accounting for approximately 11% of all deaths, with research published in 2022 from HKUMed showing a 30% increase in the occurrences of strokes at younger ages over the past 20 years.
Here’s what you should know about strokes - including how exercise can help reduce the risk of a stroke occurring.
How A Stroke Occurs
There are two primary types of strokes: ischemic and hemorrhagic.
- Ischemic strokes, which make up about 87% of all strokes, happen when a blood clot blocks an artery that supplies blood to the brain.
- Hemorrhagic strokes occur when a blood vessel in the brain ruptures, leading to bleeding within the brain.
Normally, blood carries oxygen to your brain to enable it to function properly, so when anything disrupts the oxygen levels in the brain, brain cells can become damaged, and areas of the brain stop working as they usually would.
The Effects Of A Stroke On The Body
Different portions of our brains are responsible for controlling different functions including movement, senses, emotions and thoughts, so the effects of a stroke will depend on which part of the brain has been damaged and how severe this damage is. A stroke may affect your ability to walk, talk, eat, see, read, perceive temperature, or do things you were able to do easily before the stroke.
The Effects of Exercise On Stroke Prevention
The good news is that a key factor that helps reduce the risk of stroke is very simple: regular exercise. Numerous studies have highlighted the positive impact of physical activity on the cardiovascular system, including improved blood circulation, reduced blood pressure, and better cholesterol levels. These factors collectively contribute to a lower risk of developing conditions that may lead to a stroke. Specifically:
- Exercise promotes efficient blood circulation, ensuring that the brain receives a consistent supply of oxygen and nutrients. This helps prevent the formation of blood clots that can lead to ischemic strokes.
- Hypertension (high blood pressure) is a significant risk factor for strokes. Regular exercise helps regulate blood pressure, reducing the strain on arteries and decreasing the likelihood of a stroke.
- Elevated levels of cholesterol, particularly low-density lipoprotein (LDL) cholesterol, can contribute to atherosclerosis, a condition where arteries become narrow and potentially lead to stroke. Exercise has been shown to increase high-density lipoprotein (HDL) cholesterol, which helps remove LDL cholesterol from the bloodstream.
- Keep your blood sugar and diabetes managed through your diet. As high blood sugar damages blood vessels over time and makes clots more likely to form inside them, focusing on sugar control may also help reduce your stroke risk.
Exercise Recommendations for Stroke Prevention
The American Heart Association recommends at least 150 minutes of moderate-intensity aerobic exercise or 75 minutes of vigorous-intensity aerobic exercise per week, along with muscle-strengthening activities at least two days per week. This guideline is shared by the Centre for Health Protection in Hong Kong, which recommends at least 150 – 300 minutes of moderate-intensity aerobic physical activity each week. Ideally, you want to aim for:
- Engaging in activities such as brisk walking, jogging, swimming, or cycling to get your heart rate up for at least 30 minutes on most days of the week.
- Resistance training exercises at least two days a week. This can involve using weights, resistance bands, or your body weight to build and maintain muscle strength.
- Incorporating exercises that enhance flexibility and balance, such as yoga or tai chi. These activities can reduce the risk of falls, which is essential for preventing strokes, especially in older adults.
Example Weekly Exercise Plan
- 30 minutes of brisk walking
- Strength training: focusing on upper body (arms, chest, back)
- 30 minutes of light jogging
- 30 minutes of cycling
- Strength training: focusing on lower body (legs, glutes)
- 30 minutes of brisk walking
- 30 minutes of moderate-intensity aerobics class
- Core exercises and flexibility training - yoga or Pilates
- 30 minutes of swimming
Other Ways To Help Reduce Stroke Risk
- Consume a balanced diet rich in fruits, vegetables, whole grains, and lean proteins. Limit saturated and trans fats, as well as sodium intake.
- Smoking is a major risk factor for stroke. Quitting smoking can significantly reduce your risk and improve overall cardiovascular health.
- Excessive alcohol intake can contribute to high blood pressure and other cardiovascular issues. Limit alcohol consumption to moderate levels.
- Chronic stress can contribute to hypertension. Practice stress-reducing techniques such as meditation, deep breathing, or mindfulness to promote mental well-being.
Identifying A Stroke
If a stroke does occur, being able to identify the signs early will help get the best outcomes for your loved ones or those around you. Try the FAST method for identification:
- Face: Check their face. Has their mouth drooped?
- Arms: Can they lift both arms?
- Speech: Is their speech slurred? Do they understand you?
- Time: Is critical. If you see any of these signs, you must call for help straight away.