I've never run in an underwater treadmill like Naomi Osaka has, but if someone told me to and that I'd be okay for Wimbledon, I'd jump into that weird-looking thing: Andy Roddick

Four-time Grand Slam champion Naomi Osaka is catching headlines, this time for running in an underwater treadmill.

The Japanese star recently posted a video on social media where she can be seen running on an enclosed treadmill, with water up to her waist. She suffered an achilles injury during the Madrid Open earlier last month and the treadmill is a treatment method for the injury.

"Here’s me running on an underwater treadmill because my Achilles is being stubborn still. I must be aging or something," Osaka wrote on Twitter.

After the video went viral, former World No. 1 Andy Roddick engaged in a discussion about the technique on the Tennis Channel. While the American revealed that he had never tried the exercise himself, his best guess was for it to be a remedy for Osaka's achilles issue.

"Well, I've never done it. That's probably why I didn't win four Grand Slams like Naomi Osaka. But it makes a lot of sense if her Achilles has been bothering her and she was carrying that injury into Roland Garros, maybe less in the impact but still getting the benefit of training and strength training going into Wimbledon. If I had an injury and someone told me, 'Hey, jump into this weird-looking thing and you might be okay for Wimbledon,' I'd jump into that weird-looking thing," Roddick said.

Former tennis player from America Paul Annacone also weighed in on Osaka's long-term injury and the nature of grasscourt. He termed the underwater treadmill technique as 'creative'.

"It's good for her to get some cardio and use resistance in the water. We talked about the injury that's been lingering, which is a little bit troubling going into the grass where the grass courts are so unstable. It's going to be a tricky thing, but very creative," Annacone said.

"Naomi Osaka is the type of person we need big time" - John McEnroe

Naomi Osaka withdrew from the 2021 French Open after winning the first round.

At Roland Garros last year, Naomi Osaka decided not to engage with the press after matches. The Japanese star received a lot of criticism for her decision and after winning her first-round match, she withdrew from the Major. After returning home, Osaka opened up about her struggles with mental health.

America's former World No. 1 John McEnroe recently expressed concern for the 24-year-old Osaka. The seven-time Grand Slam winner said that boycotting the media has brought her more attention.

"I worry about Naomi because she did something (boycotted the press) that at the time, she thought was right and an incredible thing. But the problem is that there’s more attention on her now. So what started out as something that was done for reasons she felt good about, now she’s probably not quite as sure about. And it’s too bad because she’s the type of person we need, big time. She whas won four Grand Slams already," McEnroe said.