"There's not as much time this time for exercise, and I'm really feeling it," admits soon-to-be mother of two Miranda Kerr

Miranda Kerr is all about keeping fit in her second pregnancy, but her busy schedule makes it challenging.

The soon-to-be mother of two — she and husband Evan Spiegel are expecting their first child together while the model shares 7-year-old son Flynn with ex-husband Orlando Bloom — stopped by for a Wednesday chat on Girlboss Radio with Sophia Amoruso, dishing on her pregnancy and life as a working mom.

“There’s not as much time this time for exercise, and I’m really feeling it,” admitted Kerr, 34. “One thing I can do with [Flynn] is put the music on and jump around, or we go for walks together around the block. He really enjoys that and I really enjoy that. We can find ways to exercise.”

“Sometimes, maybe twice a week, I’ll get in a Pilates session,” adds the former Victoria’s Secret Angel. “It’s not as much as I would like to be doing, but you’ve got to prioritize.”

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Credit: Courtesy Girlboss Radio with Sophia Amoruso

Miranda Kerr and Sophia Amoruso

“With my first pregnancy with Flynn, I would do Kundalini yoga,” explains Kerr. “I would do that every day. And I was really expecting that I would have time to do that with this baby … I said to Evan the other day, ‘Why am I not doing this DVD which I really loved doing every day when I was pregnant with Flynn?’ ”

“I was like, ‘Oh my God.’ It takes me an hour to drop my son off at school and come back,” she laments. “Then I’ve got business meetings. And then I go back and pick him up from school.”

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Miranda Kerr

The balancing act is all worth it for the KORA Organics founder, who has prioritized setting an example for her son and baby on the way.

“I wanted to make sure that I’m there for my son, to drop him off and pick him up,” she says. “I schedule all my work around his schedule … he knows that I work and he knows when he’s with his dad he’ll FaceTime and maybe I’ll be on a photo shoot or maybe I’ll be in a business meeting … ”

“He knows that, but at the same time, he knows that he’s a priority in my life, so I just want him to feel like a priority,” Kerr reveals. “So when he comes home from school, I really try to make sure that I’ve got everything I can wrapped up. I can do conference calls after I put him back to bed at night.”