Here's a few more reasons to turn off the tube: Limiting television time is a key to losing weight and keeping it off, and children who watch a lot of TV aren't nearly active enough.

Those are the findings of two new studies presented at a recent meeting in Vancouver of the Obesity Society, an organization of weight-loss professionals. The studies add to the growing body of evidence that the nation's couch-potato mentality is contributing to obesity in adults and children.

It's important for parents to set a good fitness example for their children, says Nanette Stroebele of the University of Colorado Health Sciences Center. Some ways for adults to become role models:

- Skip down one city block. It's about 200 steps.
- Park two blocks from school and walk, 400 steps.
- Play a game of soccer, 8,000 to 10,000 steps.
- Play nine holes of golf with no cart, 8,000 steps.
- Limit calories to an average of about 1,800 a day.
- Consume a relatively low-fat diet.
- Have breakfast every day.
- Eat in a consistent way without overindulging on the weekends.
- Keep track of what you eat and how much you weigh.

A study of the habits of members of the National Weight Control Registry, a group of about 5,000 people who have lost an average of 73 pounds and kept off at least 30 of them for more than six years — found that most watch fewer than 10 hours of TV a week.

That's much less than the national average of 28 hours a week, says lead researcher Suzanne Phelan, an assistant professor of psychiatry and behavioral medicine at Brown University in Providence.

Registry members who increased their TV viewing were more likely to gain weight, she says.

Previous studies on these people found that they limit their calories to 1,800 a day, eat a low-fat diet, keep track of what they weigh and exercise regularly. They walk an average of 4 miles a day or burn the equivalent number of calories in another activity.

Not watching much TV is "another strategy in the tool belt for successful losers," Phelan says.

In another study presented at the meeting, researchers at the University of Colorado Health Sciences Center in Denver had 57 children ages 10 to 17 wear pedometers for four days. They found that the children were taking an average of 7,902 steps a day.

"That's incredibly low. They should be taking at least 11,000 to 13,000 steps a day," says Nanette Stroebele, the lead researcher on the study. Adults are advised to aim for 10,000 steps a day, or about 5 miles.

One possible reason that the children took so few steps: They were watching an average of 2½ hours of TV a day.

Other findings:

• 42% of parents said they'd like their children to be more active.

• The number of steps dropped with age, especially after age 13.

About 65% of U.S. adults are considered overweight or obese; 31% of kids are overweight or at risk of becoming so.

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