Exercise not only boosts your fitness level but also promotes regularity. When you are active, so are your bowels -- and the more sedentary you are, the more slowly your bowels move. That may partially explain why older people, who tend to be less active, and those who are bedridden are prone to constipation. So, gear up and get moving. You don't have to run a marathon; a simple walking workout doesn't take much time and can be very beneficial. When it comes to regularity, even a little exercise is better than none at all.