By Dr. Mercola
Exercise is one of the best ways to keep yourself healthy. The benefits of exercise for lowering your heart attack risk, reducing stress, and helping to prevent obesity and diabetes are widely known.
Well, now you can add another big one to your list of benefits from breaking a sweat: reduced risk of stroke.
The American Heart Association reports 800,000 Americans suffer from stroke each year. Stroke is the leading cause of disability in the US and the fourth leading cause of death. Up to 80 percent of strokes are preventable, because for the most part, strokes are the result of unhealthy lifestyle choices.
Recent research published in the journal Stroke1 found that, if you're inactive, you have a 20 percent higher risk for having a stroke or mini-stroke (transient ischemic attack) than people who exercise enough to break a sweat at least four times a week.
The study involved more than 27,000 Americans for an average of 5.7 years, male and female, Caucasian and African-American. It included a larger proportion of people from the "Stroke Belt" states, where stroke rates are higher (Virginia, Tennessee, the Carolinas, Mississippi, Louisiana, Georgia, Florida, Arkansas, and Alabama).
The connection between vigorous exercise and stroke risk was very clear in men, but interestingly, less clear in women. Lead researcher Dr. Michelle McDonnell speculates that women may benefit more from less vigorous exercise, such as walking, which this study did not examine.2
Stroke Rates Increasing Among Younger People
Your risk of stroke increases with age, with most occurring after age 55. However, younger people are increasingly at risk, according to the latest statistics.
The rate of strokes among younger people (under age 55) nearly doubled between 1993 and 2005.3 The primary driving forces behind this are increasing rates of obesity, diabetes and high blood pressure—which can all increase your risk for suffering a devastating stroke.
Stress is also a significant risk factor for stroke, just as it is for heart attack. According to a 2008 study in Neurology,4 the more stressed you are, the greater your stroke risk—especially a fatal one. Heart attacks and stroke have many other risk factors in common, including:
A Stroke Is a 'Heart Attack in Your Brain'
Heart attacks and strokes are both events in which cells die from lack of oxygen. With a heart attack, your heart is the affected organ, but with a stroke, it's your brain.
A stroke involves either a rupture of an artery that feeds your brain (hemorrhagic stroke), or an obstruction of blood flow (ischemic stroke), with the ischemic type representing 75 percent of all strokes. In both types, your brain does not get enough oxygen and glucose, in addition to pooled blood putting physical pressure on areas of your brain.
And then there are mini-strokes, or TIAs (transient ischemic attacks). Each year, as many as 500,000 Americans experience TIAs, caused by temporary blockages in cerebral blood vessels, with symptoms similar to those of a stroke but oftentimes milder and shorter in duration.
Although less imminently dangerous than a full stroke, they should NOT be ignored. According to an article by Loyola University Medical Center's journal, Expert Review of Neurotherapeutics, 10 to 15 percent of people experiencing TIAs will experience a full-blown stroke within three months, and 40 percent of those will occur in the first 24 hours.5 Stroke victims experience a variety of sudden symptoms, the most common being those listed in the table that follows.
Weakness, numbness, or paralysis in one arm or leg Sudden speech difficulties Loss of coordination or trouble walking Confusion, memory loss or other sudden cognitive deficit One-sided facial paralysis or facial droop Sudden visual problems Sudden severe headache Dizziness
Recognizing a Stroke FAST Could Save Your Life
If you or someone you love suffers a stroke, getting medical help quickly can mean the different between life and death, or permanent disability. This is an area where conventional medicine excels, as there are emergency medications that can dissolve a blood clot that is blocking blood flow to your brain. If done quickly enough, emergency medicine can prevent or reverse permanent neurological damage—but you typically need treatment within one hour, which means the faster you recognize the warning signs, the better the prognosis. The National Stroke Association recommends using the FAST acronym to help remember the warning signs of stroke:6
F = FACE: Ask the person to smile. Does one side of the face droop?
A = ARMS: Ask the person to raise both arms. Does one arm drift downward?
S = SPEECH: Ask the person to repeat a simple phrase. Does their speech sound slurred or strange?
T = TIME: If you observe any of these signs, call 9-1-1 immediately.
Exercise Reduces Stroke Risk—But ONLY the Right Kind of Exercise
There have been a number of scientific studies about the benefits of exercise in stroke prevention, and recovery from stroke. Differences between men and women, in terms of the type of exercise that is best, have appeared in more than one study to date. The thing to keep in mind is, not only is it important to get enough exercise, but you must be doing the correct kind of exercise if you want to reap the benefits, which I'll be discussing in more detail shortly. Further research is definitely needed in order to clarify how much and what type of exercise is best for men and women, in terms of preventing stroke.
- A 2013 study published in Stroke7 concluded that walking at least three hours per week reduces stroke risk in women better than inactivity, but also better than high intensity cardio. This may have something to do with the inordinate amount of physical stress "conventional cardio" has on the heart, and the fact that people generally do too much of it for too long. Perhaps women are more susceptible to these risks than men.
Conventional cardio can cause arrhythmias, and in some cases, atrial fibrillation (A-fib), which is a known risk factor for stroke. It would be of value to study the effects of high-intensity interval training (HIIT) on stroke risk in both men and women, which is very different than conventional cardio. But unfortunately, when cardio has been studied, it's usually the conventional type.
- In 2009, a study in Neurology8 found that vigorous exercise reduces stroke risk in men, as well as helping them recover from a stroke better and faster. However, moderate to heavy exercise was not found to have a protective effect for women. I would expect the right type of cardio would be found to lower stroke risk in both men and women, but those studies have not yet been done.
- In 2012, Canadian researchers found that stroke patients who exercised were able to improve problems with their memory, thinking, language and judgment by close to 50 percent in just six months. Notable improvements in attention, concentration, planning and organizing, as well as benefits to muscle strength and walking, were seen among stroke patients who exercised.
- In 2008, a study published in Neurology9 found that people who are physically active before a stroke have less severe problems and recover better, compared to those who didn't exercise prior to their stroke.
Instead of Conventional Cardio, Peak Fitness Is Safer and More Effective
Several recent scientific studies indicate that conventional cardio, especially endurance exercises such as marathon and triathlon training, pose significant risks to your heart, some of which may be irreversible and life threatening. Long-distance running can lead to acute volume overload, inflammation, thickening and stiffening of the heart muscle and arteries, arterial calcification, arrhythmias, and potentially sudden cardiac arrest and stroke.
I don't think anyone can argue against the fact that vigorous exercise is beneficial to your heart and brain, but conventional cardio is just not the way to do it. This could be why the cardio benefits to women are not being detected in these studies... but that's just a theory.
Ideally, to get the most benefits from your exercise, you need to push your body hard enough for a challenge while allowing adequate time for recovery and repair to take place. One of the best ways to accomplish this is with HIIT, or high intensity interval training, which consists of short bursts of high-intensity exercise, as opposed to extended episodes of exertion. This is a core part of my Peak Fitness program, which Phil Campbell was instrumental in helping me develop. Briefly, a Peak Fitness routine typically includes:
- Warm up for three minutes
- Exercise as hard and fast as you can for 30 seconds. You should feel like you couldn't possibly go on another few seconds
- Recover for 90 seconds
- Repeat the high intensity exercise and recovery cycle 7 more times
You can do HIIT by running/sprinting (if you love running), or by using gym equipment such as a treadmill or elliptical machine, or you can accomplish the same thing without running at all by doing super-slow weight training, as I demonstrate in the video above. HIIT maximizes your secretion of human growth hormone (HGH), optimizes your metabolism and helps regulate your insulin and blood sugar. And it takes far less time than training for a marathon! You can do a complete Peak Fitness workout in 20 minutes or less.
The Importance of Recovery
Remember, adequate recovery is crucial between workouts. This includes not only resting your body, but also giving it the nutrients it needs for complete recovery. Your post-workout meal can support or impair your recovery. For instance, consuming a fast-assimilating protein such as high-quality whey protein within 30 minutes of your workout will essentially "rescue" your muscles out of their catabolic state and supply them with the nutrients they need to make their repairs. Any sort of intense exercise should also be balanced with strength training, proper stretching, core strengthening, stress reduction, good sleep and an optimal nutrition plan. You'll find much more information about HIIT and other types of exercise in the fitness section of my website.
Three Bonus Tips for Stroke Prevention
Here are three simple tips for further lowering your stroke risk—but by no means is this a comprehensive list. For more information about lifestyle changes specific to preventing stroke, please refer to this recent stroke prevention article.
- Sunshine. Sunlight causes your skin to produce nitric oxide, a critical compound for optimizing your blood pressure, which reduces your risk for both heart attack and stroke. Nitric oxide enhances blood flow, promotes blood vessel elasticity, and functions as a signaling molecule in your brain and immune system.
- Grounding. Walking barefoot on the Earth, aka "earthing" or "grounding," has a potent antioxidant effect that helps alleviate inflammation throughout your body. It also makes your blood less prone to "hypercoagulation"—so, less apt to clot—and that reduces your stroke risk.
There is a constant flow of energy between our bodies and the earth. When you put your feet on the ground, you absorb large amounts of negative electrons through the soles of your feet, which reduces the tendency of your blood cells to "clump together." Technically, grounding increases the zeta potential of your red blood cells causing them to repel each other and become less sticky, very similar to a natural anticoagulant.
Research has demonstrated that it takes about 80 minutes for the free electrons from the earth to reach your blood stream and transform your blood, so make it a point to regularly walk barefoot on grass or on wet sand for about 90 minutes to two hours, if possible.
- Fiber. If you eat more fiber, you will probably reduce your chances of a stroke, according to a report in the journal Stroke.10 For every seven grams more fiber you consume daily, your stroke risk is decreased by seven percent, according to this study.
Fiber is the non-digestible part of plants, which can be either soluble or non-soluble; soluble fiber was found to lower stroke risk the most. Soluble fiber can also help nurture beneficial gut bacteria, which are critical for good health. The American Heart Association and UK health authorities recommend adults consume 25 grams of dietary fiber each day, but I think you should get upwards of 32 grams per day and most Americans don't get anywhere near this amount.
Great sources of fiber include seeds (especially chia, psyllium, sunflower, and organic flax), berries, vegetables such as broccoli and cauliflower, root vegetables and tubers (including onions and sweet potatoes), almonds, and beans (legumes).