Instagram-famous personal trainer (and all-around badass) Kayla Itsines had a baby girl in April—but from the day she announced she was pregnant, Itsines was very vocal about her journey to motherhood and all it entailed (like how she struggled with morning sickness and restless leg syndrome while pregnant.)

Now, Itsines is opening up about one of the more difficult parts of her postpartum journey: Hitting the gym for the first time after her caesarian section—just six weeks after her daughter, Arna Leia Pearce, was born.

Itsines, a lifelong athlete, was eager to get back to working out after she gave birth. She tells Health, “My first session back at the gym, I went onto the treadmill, and I was like, ‘Alright, cool. I’m going to do a fast walk because they told me I could walk.’” 

But that fast walk didn't go entirely as planned. “I stupidly put the treadmill up to a fast walk speed that I used to be able to do. The treadmill started going. I started to feel this weird, odd pain on my right side," she says. "The treadmill pick[ed] up pace quite quickly. I started to panic; I couldn’t turn the treadmill down fast enough.”

Itsines wasn’t able to spread her legs to the sides of the treadmill so she could get off the moving track, and she grew worried she would face plant on the moving belt. Luckily, it slowed down in time for her to regain control, but that incident made her realize just how much her body had changed since she had a baby. That day she ended up walking slow for about 13 minutes. “Then I had to get off,” says Itsines.

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The realization that she wasn’t as fit as she’d like to be was a tough one. “It was a struggle, really hard. I just remember being so upset and devastated that I wasn’t able to complete [a workout],” says Itsines. That struggle is what led to her new post-pregnancy workout program, to help women who have just given birth figure out how to get back in shape in a safe way. The workouts featured in the program, which include strength-training exercises and low-intensity steady state (LISS) cardio, are 15 to 25 minutes long, and the program lasts 16 weeks.

Itsines says that one thing that made this part of her journey especially difficult was that she didn’t know what it felt like to be out of shape. “It’s different for a person who has, maybe, never worked out before," says Itsines. “For me, I don’t remember not being fit. So I was super confused.”

Itsines stressed the importance of listening to your body when you return to the gym after giving birth, explaining that this is not the time to test your limits. “If I could give advice to women, it’d be not to push them to go straight back into fitness. Not to put that pressure on them. Just take it easy.”

RELATED: Kayla Itsines’ Top Exercises for Legs, Arms, and Abs

Of course, listening to your body is important during any workout session, but you should be especially mindful of any pain you feel when you’re getting back to your workout routine after giving birth. You should also pay attention to any dizziness you experience and any tension or pulling sensations you may feel, Kayla says.

Monitoring your hydration and energy levels is important, too. “You’re sleep deprived. Listen to your body; if you need sleep, then sleep,” says Itsines.

While getting back in shape after having a baby might seem overwhelming at first, it’s definitely not impossible. Like most fitness goals, it requires taking baby steps, for lack of a better word. Luckily, Itsines says that the scary treadmill incident on her first day back didn’t scare her away from the gym the next day. “I went back every day. I just showed up and tried to do as much as I could. Maybe it was just a five-minute walk or some arm workouts that went for five minutes or two minutes, whatever I could handle,” says Itsines. “I just did that and slowly built up my strength to be able to do a workout.”

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