A 2003 meta-analysis of studies found that highly active individuals reduced their risk of stroke by 27 percent while moderately active persons had a 20 percent lower risk.
More recently, a Danish study [Neurology, October 21, 2008] concluded that subjects who exercised tended to have less severe strokes and a better chance of recovery compared to inactive persons. Of 265 patients who had suffered a stroke, those who exercised most before their stroke were two and a half times more likely to have a milder stroke and a more complete recovery compared to those who exercised the least.
To reassure those who do not consider themselves athletes, the authors wrote that “staying fit does not have to be a scheduled regimen. For the people in this study, exercise included light housework, taking a walk outside, lawn care, gardening, or participating in a sport.”
BP Is Major Risk Factor
Among risk factors for stroke, high blood pressure is usually ranked at or near the top, and exercise has shown to lower blood pressure. Diabetes is another major risk factor for stroke; and exercise has been shown to reduce blood sugar and decrease insulin resistance. Exercise also helps control weight and has a good effect on cholesterol, two other stroke risk factors.
For lowering blood pressure, the ideal activity is aerobic–using large muscle groups in the legs and torso for sustained activity over 30 to 45 minutes most days of the week. The intensity level should be high enough to raise your heart rate and cause you to breathe a little harder.
One study found that higher intensity exercise had a greater effect on blood pressure while longer duration was more likely to improve cholesterol, especially HDL.
Strength training with weights was once considered dangerous for persons with high blood pressure, but recent research has demonstrated that progressive resistance exercise of moderate intensity is beneficial–lowering both systolic and diastolic blood pressure by 2 to 4 percent.
Exercise works by strengthening the heart, allowing it to pump more blood with less effort. In inactive individuals, the heart tends to weaken with each passing year, but exercise counters this effect at any age. Because blood is continually being forced through arteries, exercise also improves the function of blood vessels, making them stronger and more pliant.
All of these exercise benefits take about one to three months to acquire (that’s what “training” is all about) and a lifetime to maintain. Stop exercising and the benefits fade quickly.
If you’re over age 50 (40 for a male) or have a medical condition such as heart disease, hypertension, high cholesterol, diabetes or obesity, check with your doctor before jumping into a new, more vigorous activity. To avoid injury, start slowly and build up gradually with careful attention to warming up, cooling down and stretching.
After a stroke occurs, the greatest danger is recurrence, and nearly one third of stroke survivors have at least one more stroke. In many cases, these stroke survivors are overweight and have rather severe cardiovascular disease and/or diabetes. Even those who were previously fit have suffered significant damage. Theoretically, the stroke survivor has much to gain from regular exercise, and recent studies have confirmed the benefits.
In one randomized, controlled study, 42 stroke survivors with partial paralysis showed dramatic improvement in cardiovascular fitness after a 10-week program of vigorous aerobic training–an effect similar to that expected from healthy older adults.
Subjects in a 12-week progressive resistance training program showed 68 percent improvement in leg strength on the affected side plus improvements in gait and balance.
In the past, it was believed that most, if not all, recovery of motor function occurred within the first few months after a stroke. As a result, physical rehabilitation programs usually ended at that time. Recently, however, aggressive rehabilitation programs have been used effectively well beyond that time period. The treadmill is ideal for such programs because, if necessary, the patient can use handrails or harness devices for partial or full support. For those with gait problems, changing the treadmill grade while maintaining a comfortable speed can increase intensity.
One study published in Stroke [August 28, 2008 online edition] found that 37 stroke patients with long-term mobility impairments showed changes in subcortical areas of the brain as a result of a six-month treadmill exercise rehabilitation plan. Their walking speed increased by 51 percent, their cardiovascular fitness, by 18 percent. Stretching programs, by comparison, did not activate the brain in the same way.
Heart attack, stroke and sudden death can occur during exercise. That’s why patients are tested and supervised during rehabilitation when the physician feels such monitoring is necessary.
Exercise, however, is a normal activity. It is sitting on the couch that is dangerous to your health.
Kerri T. Musselman, PharmD
