"It's just not in my future," the actress told PEOPLE at Wednesday's Brita Burbank YMCA special event, which celebrated the company's donation of water filtration pitchers and dispensers to YMCA locations across the country.
As children played and made their own fruit-flavored water at the outdoor event, Longoria, 39, explained what drew her to the cause.
"With kids, I love their energy and spirit and innocence," she said. "It's really important for us to be here today to talk to them about water because that stays with them. Water's the original energy drink. Water is really good for you. Water can be fun."
The Devious Maids producer – who's dating Mexican businessman Jose Antonio Baston – also shared her secrets for staying in shape.
"I run a lot. I'm a big runner. And I do yoga," she said. "So, I just alternate. Run, yoga, run, yoga. I do weight training as well."
And though she's all about staying hydrated, you won't find Longoria sipping from a disposable water bottle after a workout.
"So many end up in the ocean so I've banned them from the house," she said.
Michael Kovac / Getty
Reporting by MATTHEW COLE WEISS