If your job keeps you on the road, you know how hard it can be to find time for a workout in between conferences, sales meetings and business dinners. But for travelers who make regular exercise a priority while at home, missing a workout can leave you feeling sluggish and out-of-sorts. Multiple studies show links between physical fitness and brain function, and experts at the President’s Council on Physical Fitness agree that as little as 20 minutes of activity a day can keep energy levels up and fight fatigue in adults. – From Forbes