Let's face it: When you try to keep up with the activity level of a kid, you quickly begin looking and acting your advanced age. Most kids have no shortage of energy -- or ideas of how to expend that energy loudly and dangerously. However, there is no shortage of sedentary activities and distractions vying for children's attention, such as television, the Internet and video games. Children should get at least an hour of exercise every day. Exercise helps kids alleviate stress, get fit and sleep better at night, not to mention the positive effect it has on self-esteem.
As we age, our priorities shift. It might be great to run circles in the yard for hours on end with a pirate costume on, but by the time you hit puberty, that doesn't sound like a good idea anymore. In fact, the entire notion of imaginative play seems to go out the window with puberty, and most thoughts are concerned with saving face, impressing members of the opposite sex and dominating (or at least peacefully coexisting with) peers.
We may still play sports in middle and high school (helping us achieve our primary goals of reputation and romance), but most of us aren't going pro when we leave high school, and organized athletics aren't usually a fixture in an adult's life. While a kid pursues a ball across a field, young adults consume most of their time pursuing either a career, a significant other, an active social life or a college degree (and sometimes all of the above).
Around one in six children and teens are overweight [source: CDC Foundation]. While there have been correlations made between being overweight and feeling less happy (perhaps as a result of teasing, social isolation and athletic exclusion), one study found that kids who consumed lots of fast food and soft drinks had a higher risk of being overweight, but a lower risk of feeling unhappy [source: Chang]. How that fits into the larger picture of childhood obesity has yet to be seen.
And while physical health and well-being are important to happiness, mental and emotional health issues can weigh heavily on children's happiness, especially when left untreated. Around 20 percent of American children are estimated to have an identifiable mental health disorder that requires treatment, from anxiety disorders and depression to schizophrenia and ADHD [source: Substance Abuse and Mental Health Services Administration].
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