Heidi Klum: The One Thing People Always Get Wrong About Me

Turning 40 hasn't slowed Heidi Klum a bit!

Since her milestone birthday earlier this month, the supermodel-turned-reality TV star has posted a flurry of workout photos on Twitter. In them, the mom-of-four can be seen impressively catching air as she sweats it out, in gear from her own New Balance line, among the masses of New Yorkers, and she tells omg! that just opening up her front door and heading outside is her favorite way to get exercise.

"It's just easier for me to exercise that way. I don't have to drive anywhere. I put my outfit on, I go outside, and I run on the West Side Highway [path]. Everyone else runs there, so it's not weird," Klum says at the Shutterfly by Design in Manhattan on Wednesday.

Well, it might be a little "weird" to be a runner who realizes that the woman who just blew by her was Klum. But it's something people are probably used to, at least in New York and Los Angeles, as the "America's Got Talent" judge says she doesn't have a home gym, as many other stars do ― and that's not the only perk she lives without.

"I don't have a gym at home ― and I don't have a chef either," she tells us. "I don't know why people always think I have a chef and a trainer and all that. People always write about it and they keep writing about it, [but it's not true]."

One thing she does spring for? Home art lessons for her children ― Leni, 9; Henry, 7; Johan, 6; and Lou, 3 ― who she reunited with early Wednesday morning after their trip to visit their father, Seal, in Sydney, where he had been shooting "The Voice" Australia.

"We do have art classes. I have someone come to the house," says Klum, who has been dating her bodyguard Martin Kristen since soon after her split from the British singer in 2012. "Shakuntala [Zakheimis] is my children's teacher. She's very interesting and comes up with all these unusual ideas."

The artwork of her little ones is displayed on the walls and pillows throughout the children's bedroom Klum decorated in Shutterfly's Manhattan townhouse to showcase some of the photo company's new products. The room also features items from the German beauty's Truly Scrumptious line at BabiesRUs.

"I said to my children, 'Please hook me up with some paintings I can take,'" she says to the reporters, pointing to their masterpieces. "My son Johan is the biggest artist out of all my children. He can sit at the table and just paint for hours. He's very into it, [but] he's 6 years old, so it's like snot out of the nose" of his various monster paintings.

Now that she's reunited with her kids, Klum says she has some fun activities planned for the summer.

"We're going to Splish Splash," she says, referring to the Long Island, New York, water park. Broadway is on the family's horizon as well. "I also have tickets for "Annie," "Matilda," and "Spider-Man [Turn Off the Dark]."

There will also be family trips out to eat at their favorite high-end Japanese restaurant.

"Their favorite restaurant is Nobu," Klum says with a laugh. "My daughters love the yellowtail [sashimi], especially my oldest. She always wants to eat there. [But] they're so well-behaved. They eat with the chopsticks. I try to educate their little palates."

As for whether there will one day be more little mini-mes, she's pretty quick with her response.

"I don't think so. Four is a lot!"

Four is a lot, but if you take another gander at those workout photos, her energy level seems boundless.

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