Kids, I'd like to talk about a little something here. Sugar.
Sugar does not cause hyperactivity in children. Can we please remember this rather than give children the idea that giving them candy is an excuse for them to behave like morons because, "Sugar makes me hyper!"
Sugar, in fact, keeps little kids active. They're growing, they're active, if they don't get enough types of both simple and complex sugars, they end up falling asleep and getting sick. This is why fruit is really good for kids, but, in moderation, this is also why candy is good for them- they need it. In regards to sugar, kids (excepting diabetics) can be pretty safely reckless because they have things like metabolism and burn energy like the little candles they are.
The difference here is the difference between sugar and caffiene. Kids don't need much caffiene, they get the required result from sugar alone and just from being alive. So, yeah, if you're going to fill a kid up with Mountain Dew and then take him to a movie, he's going to be a little more restless than usual. And not just because he has to pee.
Overweight kids come from too much fat, and too much caffiene, and not enough exercise compared to the amount of these they're consuming.
The exercise is a big one, but, consider what is a common forth grade experience. You wake up to catch the bus which takes you to your school half an hour's bus ride across town (I was one of the few kids I knew to walk to school, and that stopped when I started fifth grade). Then you sit in school until you get your half hour of recess. If you're lucky, you have a second 15 minute recess, or it's gym day. Other than that, you're pretty much sitting in a desk and letting the Ritalin do its work. Then you ride the bus half an hour home. If it's wintertime, it's probably almost dark outside by the time you get home, so you can't go out and play, so you watch television, do your homework, eat dinner, and go to bed. Exceptions are kids with dance classes, sports teams, etc. Other than that there isn't a lot of time in the day for a kid to burn off that energy.
One of Little Miss Additude's favourite things to believe about herself is that she's annoying and hyper. She takes pride in it. The fact of the matter is that she's just a really energetic kid. If they would send her outside and say, "OK, run! Run for an hour and we'll go back inside and have math class," she would be just fine.
As the days get longer, it's brighter longer, so there's more time for the running around, but on the whole, kids without activities are running in the same schedule as grown ups are. Grown ups complain that they don't have the time to fit exercise into their schedules, and then wonder why they feel unmotivated and tired.
On the whole, we've set our lives up so that we do as little movement as possible. Compare the work most people do in one day to any page of a Laura Ingalls Wilder book. There's a definite difference.
Grown ups need to learn to live like kids should be able to live. Cut out the caffiene, cut back on the fats, keep active, and manage your sugars well.