Olympic gold medallist Kyle Chalmers has arrived home to Adelaide, finding just enough time in his schedule for a burrito and to visit his former school.

The 18-year-old revealed he had been suffering from pneumonia since returning to Australia and would only take part in Olympian parades in Melbourne and Adelaide if he was well enough.

The 194-centimetre Year 12 student said his life had become a "rollercoaster" since winning the 100-metre freestyle event at the Rio Olympics and becoming famous.

"You come off such a massive high winning an Olympic medal," he said.

"You get thrown into doing all this media and appearances for people.

"It's been a massive couple of weeks actually and my body's starting to feel it. I'm feeling a little run down."

Today's appearances included visiting Immanuel College where he was a student until the rigours of competitive swimming forced him to study Year 12 online.

"I'm here for a couple of days and then we have the welcome parades around Australia," Chalmers said.

"Then I'm off to Germany to do some things for Adidas and then we're doing a photo shoot in Marseilles, France."

After that, Chalmers said he would travel to London for a five-day holiday.

"I'm going there to watch Arsenal play. I'm a massive soccer fan. That will relax me. Then I'll be back into training."

Chalmers reunites with favourite food

Speaking on ABC 891 Adelaide, Chalmers said the first place he visited after returning home was a burrito restaurant at Glenelg for his favourite food.

Kyle Chalmers reunites with his school principal and classmates. ( ABC News: Alex Mann )

"I get a Californian Burrito, which actually has fries in the middle," Chalmers said.

"The manager noticed me and came over and said, 'we've just realised who you are. What do you want? You can have anything for free'."

He also revealed a little of the strategy behind winning the 100-metre freestyle - the first Australian to win the event since 1968.

"The only swimmer I could see [at the turn] was Canadian Santo Condorelli," he said.

"I turned and could see he was about a body length in front of me."

He said he swam the first 50 metres on the lane rope to get the wash, knowing Condorelli was going to come off the block "pretty fast".

"If you swim close to their wave, you can actually surf that in a way," he said.

"You can kind of save energy while they're working so hard and then you come up and move back into the middle of the lane, and you start working hard so they can't catch your wash.

"There's definitely strategy, maybe not in the 50-metres because that's just an all-out sprint, but there's strategy in every race."

Claims of Olympic divide 'untrue'

Chalmers also spoke of alleged controversy within the Australian Olympic team.

He rejected claims by Fairfax Media there was a divide between swimmers and other athletes in the Olympic Village.

"We mixed in with the other sports. I don't know where that's come from," Chalmers said.

"The whole one team thing was evident on the plane yesterday when we flew home.

"We had silver medallists and bronze medallists sitting in economy so that people in the media, and people in the AOC [Australian Olympic Committee] and the basketball team were able to sit up front in business," he said.

"It didn't make a lot of sense.

"There was a lot of fuss about that because the people who earnt those medals didn't get to sit in business class like they were promised."