The CDC and the AHA recommend that adults spend a minimum of 30 minutes a day, five days a week, doing moderate-intensity exercise, or at least 20 minutes a day, 3 days a week engaged in vigorous activity.

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These recommendations include at least 60 minutes of moderate-intensity aerobic exercise a day, such as brisk walking, plus high intensity activity three times a week.

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To reduce the risk of the disease accelerating, the recommendations included 60 minutes of brain exercises daily, 15 minutes of moderate-intensity physical exercise and avoidance of medications that might worsen the condition.

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The 2008 Physical Activity Guidelines for Americans released by the Department of Health and Human Services recommends that adults age 18 to 64 engage in at least 2.5 hours of moderate-intensity aerobic exercise (brisk walking, biking) or an hour and 15 minutes of vigorous activity (like running) each week.

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