Khloé Kardashian Bares Her Beach Bum in Cheeky One-Piece Swimsuit While on Vacation in Mexico

Khloé Kardashian has been very open about her post-baby fitness journey, sharing candid details of her workouts, diet and weight loss with her fans on social media. And the reality star has clearly gained back her swimsuit confidence.

Kardashian, who welcome daughter True Thompson four months ago with boyfriend Tristan Thompson, hit the beaches of Puerto Vallarta, Mexico, in a cheeky one-piece (her favorite swimsuit style!) which put her famous curves on display. The new mom is on vacation with her boyfriend, sister Kendall Jenner and the model’s basketball player beau Ben Simmons.

“Khloé and Tristan seemed very happy,” a photographer source tells PEOPLE of the new parents on vacation. “Lots of cuddles and love all weekend. They definitely enjoyed themselves.”

Kardashian returned to the gym six weeks after giving birth, as soon as she got clearance from the doctor. But the star revealed it took her time to get back into her routine.

“The first day, I could not do the most simple things. I was out of breath. It was just different. And I kind of felt really defeated. Like, ‘Oh man. I don’t know if I can do this,'” she said. “After the first week I was like, ‘Okay. I am feeling a little better.’ I am not breathing so hard. I don’t need as many breaks. But I would say really after three weeks was when I felt good.”

As for adjusting to mom life, the star says she has a new-found appreciation for what her sisters went through.

“You’re f—ing tired,” she said about motherhood. “I just said to my sisters [Kourtney Kardashian and Kim Kardashian West], ‘How do you have more than one kid?’ I am exhausted. I am taking the [baby] monitor to the garage, I am trying to get [workouts] in. And it is hard. It is really hard. And you’re just tired. Your hormones are different. It is just a mindf—-!”