Approximately 14,000 people are competing in this year’s Eva Air Brisbane Marathon, from babies in prams all the way through to an octogenarian.

Gold Coast resident Michael Byrne, 83, has run more than 40 marathons in six different countries, but it’s Brisbane’s unique scenic course that’s brought him back for five years.

“It’s never too late” to start, said Byrne, who picked up running at the age of 50.

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This year’s participants will complete a 42.2km loop from the Botanical Gardens, across the Story Bridge, through New Farm, and then to Kangaroo Point on Sunday.

“Last year alone, more than 10,000 runners from 35 countries participated, and I’m always amazed by the spirit of everyone who comes to cheer them on,” Lord Mayor Adrian Schrinner said.

The Story Bridge will be open to runners for the first time since Cyclone Alfred, when the pedestrian paths were closed.

“It’s a beautiful course and that’s why people do these events,” marathon spokesman Jason Crowther said.

Beyond the course, it’s also about giving back.

Now in its 33rd year, the sold-out event has so far this year raised over $300,000 for charities.

“We do impact the community with road closures ... (so) we make sure that the event is a big supporter of community and charity, just to thank the residents and the businesses (in the area),” he said.

Crowther said the event has attracted younger participants too, as some kids will be pushed in prams by their parents in the two-kilometre event.

“There’s definitely a resurgence in running at the moment, post COVID we’ve seen a massive boom.

“There’s a massive shift of health and fitness within that younger community now, and I think it’s great.

“These sorts of events give that younger generation a reason to get outdoors and get active and not just sit behind the screens.”

First time entrants will make up about 70 per cent of the participants at the marathon.

As Byrne prepared to lace up for the weekend event, he said “consistency” is key.

“Don’t take a month or too off, keep going,” he said.

“Stick to your pace ... don’t run off like it’s a hundred-yard dash.”