As millions across Australia face lockdown, the champ had a simple message: "COVID is no joke."

"We're so fortunate in Australia," Volkanovski said.

"It's hard to comprehend how bad it is overseas, and as hard as it is, staying home, staying safe and letting authorities do their thing for the greater good has never been more important."

As well as conducting private training ahead of his next fight later in the year, Volkanovski, 32, is currently locked down at his NSW Illawarra home with wife Emma and their two girls, Ariana, 5, and Airlie, 3.

Volkanovski's COVID nightmare led to the postponement of his title defence one week out from facing Brian Ortega back in March.

Volkanovski was hospitalised in Las Vegas and placed on oxygen after being diagnosed with COVID pneumonia.

"I was probably the fittest I've ever been, and to put that in perspective, me at 70 per cent fit is still really fit," he said.

"It was probably the thing that saved me. If I had underlying problems, things definitely could have been a lot worse.

"It started with a headache, but it wasn't long before the symptoms got worse - fever, night sweats, body aches and then it began to impact my lungs and ability to breathe, and then I started coughing up the phlegm with the blood.

"At that time, I was diagnosed with COVID pneumonia, but it was mild, and my oxygen levels were good, but it wasn't long before that declined.

"First it was my oxygen levels dropping and then my heart rate. At one point, my heart rate was sitting at around 37 beats per minute. To put that into context, your average male would be counting between 65-100, so it was low, low, and I was really worried about the damage that might be doing to my heart.

"Fortunately, they were able to control it, and on medication, it was only a matter of days before my conditions began to improve."

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The UFC star said he made a "pretty quick" recovery physically, but due to COVID pneumonia, he still tested positive for another three weeks despite no longer being infectious.

Four out of the eight members of the Volkanovski camp got the virus while in Las Vegas, including rising MMA star Colby Thicknesse.

Mount Warrigal resident Thicknesse, 22, is Volkanovski's training partner.

"It didn't hit me too badly to be honest," he said.

"I had some fatigue for about three days, and just a couple of body aches here and there. But other than that ... besides not being able to train hard because it affects your lungs, I was still pretty healthy during the whole period.

"Probably the worst part was losing my sense of taste and smell. I lost my taste for just over a week, but I lost my smell, it was like two-and-a-half, three weeks before it came back completely.

"It rocked Volko hard, but there were a few of us who had a few symptoms of that, but didn't get it so badly.

"So it's unpredictable in that way."

Thicknesse was due to fight on the Gold Coast on July 17, but it has been postponed.

Thicknesse urged the Illawarra to take lockdown restrictions seriously.

"We were infected without knowing it - we were just lucky that half our team didn't catch it as well," he told the Mercury.

Volkanovski said while he didn't want to push his support for vaccination on the public - "I'm not here to change anyone's opinions" - his perspective on COVID-19 and the physical impact it could have was altered by his experiences.

"I thought being one of the guys that's young, fit and healthy, I should be sweet," he said.

"I was fitter than ever going into that fight. But sometimes these things don't discriminate."

In the meantime, Volkanovski, who is a coach on the current season of The Return of The Ultimate Fighter reality TV program, encouraged the Illawarra to make the most of their circumstances during lockdown.

"Family is everything to me anyway," he said.

"So now's a good time to spend time with your families, and be present for them.

"For me, I've been getting right into doing activities with the girls.

"I've been getting right into drawing and that with the kids. Sometimes we don't have this sort of time on our hands... I know it can be tough being in the house, but you can do things like diet, make your own food, still try and keep fit while this is all happening, and make the most of this opportunity.

"There's things that we can't do and there's things that we can do... Rather than be upset that you can't do certain things, you can try and stay positive through these hard times and do what we can."

The champ's tips on staying active in lockdown:

*Exercise. "It's so important for your health, both mentally and physically. We're still allowed out for fresh air and exercise - use that time wisely. A brisk walk, bike ride or more intense sessions,- it doesn't matter as long as you're moving."

*Cook. "I love my food and love to cook, so this is a no brainer for me, but it can also be a great way to learn new skills, have a bit of fun and kill a few hours. It's also great if you've got kids -be ready for a lot more mess."

*Upskill. "Use the extra time in each day to learn a new skill or work on old ones - whether you want to get into MMA, boxing or learn to draw. Whatever your passion is, spend time embracing it."

*Declutter. "Go through things that you no longer need - clean home, clean head."