Speaking ahead of the season-opening Brisbane International, the 26-year-old Sabalenka said she wanted to ensure her rivalry with the Polish world number two did not become too intense.
The pair practised together in Abu Dhabi last week, which Sabalenka then posted to TikTok.
"I thought we have to stay together and have fun and just enjoy our rivalry, not be too tough on each other," Sabalenka said.
"So I asked (her to train with me) and we did it.
"Then I was doing fitness after our hit. She was like, I can join you guys. We filmed it and posted it.
"It's been becoming more chilled between us, too," Sabalenka added.
"I have to say she's a really nice person. It was fun to get to know each other."
Sabalenka will warm up for her Australian Open defence in the heat of Brisbane, while Swiatek is playing at the mixed-team United Cup in Sydney.
The Belarusian has won the past two titles at Melbourne Park and could become the first woman since Martina Hingis in 1997-99 to win three Australian Open crowns in succession.
But she insisted she was not focusing on that milestone.
"Honestly, I didn't know about that till probably a few days ago when I saw it on Twitter," she said, referring to the platform now called X.
"I mean, it's a little bit cool to achieve such an incredible goal, a dream of so many young players.
"But once again, I think I better focus on myself. If I'll be able to bring my best tennis, I know that I'm able to do that."
Sabalenka also said heading into the Australian swing as world number one made no difference to her approach.
"It doesn't matter what's your ranking," she said.
"You have to go there, compete, fight, do your best. It doesn't matter whether you're one, two, three or 100."
Sabalenka has a first-round bye before playing either Viktoriya Tomova or Renata Zarazua in round two.
