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By People.com/Alexia Fernandez
Jul 02, 2018 @ 4:00 pm

Pippa Middleton is taking pregnancy fitness tips from another famous mom.

In her latest column for the U.K. supermarket monthly Waitrose Kitchen, Pippa—the younger sister of Catherine, the Duchess of Cambridge—divulged some tips on how she keeps in top shape while pregnant and the star she looked up: Serena Williams.

The fitness enthusiast is expecting her first child with husband James Matthews.

“I’ve been a tennis fan since childhood, as a player and spectator, and have been keen to continue playing safely throughout my pregnancy,” Pippa, 34, writes.

“Take Serena Williams,” she continues. “She famously proved that women can play a high level of tennis from two months (when she won the 2017 Australian Open) up to eight months.”

“Few of us can relate to this elite excellence, but if you’re a healthy, well-trained player with an uncomplicated pregnancy there’s no reason why you can’t continue a good level of tennis,” she writes.

The important thing to keeping healthy and exercising during pregnancy, Pippa writes, is to enjoy “releasing energizing through rallying, footwork and working on core strength.”

And the best piece of advice she gives when it comes to playing a sport while carrying to term?

Pippa says she’s been told to “keep two feet on the ground when hitting strokes and to avoid sharp turns and quick movements, particularly as I approach the due date.”

The mom-to-be confirmed her pregnancy in her column earlier this month, in which she revealed that she did not battle severe pregnancy sickness, or Hyperemesis Gravidarum (HG), unlike her older sister.

Bertrand Rindoff Petroff/Pierre/Getty Images

“I was lucky to pass the 12-week scan without suffering from morning sickness. That meant I was able to carry on as normal,” Pippa wrote, as reported by Hello! magazine.

In September 2017, Kensington Palace announced that Kate was pregnant with her third child — and noted that she was once again battling HG, similar to when she was carrying Prince George, who turns 5 on July 22, and Princess Charlotte, now 3.

Though Kate was unable to carry out her royal duties during the first months of her pregnancies, sister Pippa was able to continue her everyday schedule, though she admitted she had to make some slight changes.

“When I learned the happy news that I was pregnant, I realized I needed to adjust my four to five-day-a-week [fitness] routine,” she wrote, noting that she kept her pregnancy a secret from her gym instructor until the “riskier months” were over.

Pippa also shared how fitness has been an integral part of her pregnancy.

“I’ve noticed my body change, but through exercise, I feel it’s being strengthened,” she wrote.