So, how do you motivate your children to stay active - or get active - when school's out?

Jake Steinfeld, chairman of the California Governor's Council on Physical Fitness and Sports, has plenty of tips. The man famous for his "Body by Jake" program also is founder of Major League Lacrosse and Exercise TV, but remembers another time - "I was a fat kid with a bad stutter" - and knows firsthand that lives can change with fitness and good nutrition.

His No. 1 tip for parents: "Lead by example. Your children are watching you."

An exercise pro's tips for incorporating fitness into your family's summer fun:

- Set limits on screen time.

"It's one thing to dictate you can only be in front of the computer or TV X amount of time a day," Steinfeld says. But make sure you're following your own rules. If the kids see you watching endless hours of TV or playing cards on the computer, their logical reaction will be to do the same. "Make a conscious effort to get off your 'buttissimo' and do something active with them. I know that's very easily said and it's a lot more challenging to do."

But he says you can do it, just as he does with his four children - Morgan, 15, Nick, 13, Zach, 8, and Luke, 6.

- Make it challenging.

Steinfeld says fitness should be fun, not drudgery. "I have a gym; a lot of people don't. But I never push the kids to get in here. I do tell them, if they come in and want to watch the TV, 'You have to do push-ups or sit-ups during the commercials.'"

With three sons, he says there's inevitable competition among them - and their sister - so challenging them to contests with fitness in mind is easy. "It takes the work out of working out," he says. "I do it all day long with my family," making a game out of everything from seeing who can pick up the most clutter in the back yard to everyday rituals.

"I say to them, 'I'll time you and see how long it takes you to get upstairs, change into your pajamas, put your clothes down the laundry chute, brush your teeth and get back down here.' If fitness is made to be fun for them at an early age, they'll do it when they're grown-ups."

- Create opportunities.

"There are a lot of kids who don't feel confident in themselves," Steinfeld says, recalling the days when he would be picked last for a team. "Many kids just don't feel like participating."

But there are alternatives to team and school sports.

"Dance Dance Revolution is a really fun activity you can do indoors," he says, "and Wii-type games are good exercise."

- Good nutrition is not spelled d-e-n-i-a-l.

"I train so I can eat," Steinfeld says with a laugh. "I love to eat."

But what kids eat and what parents serve them is important, Steinfeld says. Just be realistic.

"Start out a little bit at a time," Steinfeld says. "You don't need to become a connoisseur of health food."

In his family, there are occasional splurge days where M&Ms and pizza are OK. The goal is to eat healthy and fresh meals the majority of the time, with treats in between, not the other way around.

- Get outside.

"Take the dog for a walk as a family," Steinfeld says. "Go to the park after work. Maybe it's a bike ride on the weekend or a hike in the park or just going out in the back yard together."

The bonus is a chance to talk about the day, catch up with each other.

- Choose activities they will enjoy.

"I'm a huge believer in team sports for boys and girls," Steinfeld says, "but not too many. There has to be down time."

He and others suggest checking out the neighborhood Y, seeing what classes are offered that interest your child, or sign up for yoga or another activity you can do together at the community college or rec center. But don't overdo it.

"It's summer; stay away from structure," Steinfeld says.

Just go swimming - "an awesome exercise" - he says, or rowing on a lake. Or try kayaking - "great upper-body exercise" - and even workout videos.

ESPECIALLY FOR TEENS

From kidshealth.org comes this advice for motivating teenagers to be active: It's a good idea to give your child control over how he or she decides to be physically active. Since teens are defining themselves as individuals and want the power to make their own decisions, they are reluctant to do yet another thing they're told to do.

- Support your child's choices by providing equipment, transportation and companionship.

- Create opportunities for them to be active with their friends.

- Your teen may not have time to play a team sport at school or in a local league, but many gyms offer teen memberships, and your teen may be able to squeeze in a visit before or after school.

- Your teen might also feel more comfortable doing home exercise videos.

- Try coordinating your teen's exercise schedule with your own.

- Talk with your teen about limiting time spent in sedentary activities.

Recent studies have shown that teens, on average, are spending more than six hours a day on various media, including watching television, listening to music, going online and playing video games.

"If we can just get this across here that this is about a lifestyle change," Steinfeld says.

And about turning around what he calls a sad prediction: "This generation of children, our children, might not outlive their parents. That's a scary thing."