TEMECULA -- It'd been 45 minutes, the kids were tired. But it wasn't over yet. Moving from the playground equipment-looking treadmills and stationary bikes, the group of 18 kids was now to do a set of jumping jacks.

"I did a hundred million once," shouted 6-year-old Phillip San Angelo as he began to whip his arms up and his legs out.

Toward the end of the first Temecula kids fitness program, Phillip was among the most energetic, running when others walked on the bright red, yellow and blue treadmill. His twin sister, Mia San Angelo, was less.

"I'm tired," she told instructor Margie Garcia as she flopped to the ground, her feet sheltered in cupcake tennis shoes stretched out in front of her.

But that wasn't enough of an excuse. With a few encouraging words and after a few sips of water, Mia rose to her feet and began walking with the others in the cool-down circle, in which they also sampled carrots and tangerines.

Saturday was the first session in an eight-week program offered by the Temecula Community Services Department. In the following weeks, children ages 3 to 9 will participate in an hourlong workout that focuses mostly on cardiovascular fitness and they'll also learn healthy eating tips.

The start of the program at Harveston Community Park in Temecula made some children push themselves reluctantly. One boy who said he only eats potatoes and ketchup had to be convinced to try a carrot. A girl complained that she was "sweating and dying" as she peddled away on a stationary bike. But others seemed to enjoy seeing how much they could strengthen their bodies during the session.

"I think in preschool they're talking about the heart," said Lori Reams, mother of 5-year-old Ayden Reams who recently has taken to doing push-ups and jumping on his mom's elliptical exercise machine. "He just keeps saying he needs to exercise."

The exercise circuit designed by Garcia incorporates a group-workout feel. Children are encouraged to contribute to a group calorie-burning count, rather than individually checking how much they are burning. This, she said, takes the pressure off the individual child to burn as much as he can.

"This is an intense workout," Garcia said.

Letting her kids use a lot of their energy was a big reason of why Lisa San Angelo enrolled her twins, Phillip and Mia. While they are always active, they always have more energy. And while both her children are petite, San Angelo said another concern of hers was the growing trend of child obesity -- one she wants her family to continue avoiding.

"I've heard a lot on TV about obesity because of all the junk food," San Angelo said. "Sometimes as a parent it's hard to say no (to requests for treats), so it's nice to teach them some healthy habits."

Another session of the eight-week fitness course, which costs $64, is set to start in April. For information or registrations call 694-6480 or visit www.cityoftemecula.org.

Contact staff writer Nelsy Rodriguez at (951) 676-4315, Ext. 2626, or nrodriguez@californian.com.