Ten years ago, the federal government released its first set of exercise guidelines designed to keep adult Americans healthy. As Gretchen Reynolds reports in the New York Times, the feds recommended 150 minutes a week of moderate-intensity exercise, 75 minutes of vigorous exercise, and some type of strength training twice a week, among many other specifications. Now, as of last week, a second set of guidelines has been released, and they look a lot like the previous guidelines. What’s new and different? The new guidelines include balance training for older people, and they expand the definition of exercise to include shorter bouts. While the original guidelines wanted each bout to last at least ten minutes, the new rules graciously accept briefer activities, and even more graciously, they include things like walking up stairs and other activities that we may not consider “exercising.” So yes, it just got a little easier to tell ourselves that we are getting enough exercise.