Australia's fastest woman wants to break her own national record, but sprint queen Melissa Breen will be unusually slow when she races on Sunday.

Breen will walk the five kilometre Canberra Times fun run to raise awareness for the Heart Foundation more than a year after her dad, Mike, had a heart attack.

She will walk as part of her active recovery as she continues a five-month training plan of 12 sessions per week, edging closer to a 100 metre sprint return in the coming months.

The two-time Olympian has set her sights on the Commonwealth Games on the Gold Coast and her first competition races in the United States next year.

But the motivation driving her racing comeback is the goal of beating her personal best time of 11.11 seconds after he broke a 20-year-old Australian record three years ago.

"I really just want to run fast, that's all it comes down to," Breen said.

"Breaking that record again and getting as close as I can to getting under 11 seconds is what drives me every day.

"I know it's hard to run that fast - no one did it in 20 years. It requires something special but I'm working hard every day to get back to that and be a bit better. That's my driving force."

Breen will be part of the thousands competing on Sunday morning for the annual fun run event.

She has teamed up with the 'Heart Racers' program and will walk five kilometres, giving her plenty of time to reflect on the reason she's doing the fun run.

Mike Breen thought he had hard burn last year and drove himself to the emergency department the following mornings. Doctors told him he had a heart attack and there was a 90 per cent blockage.

"Dad won't be doing the fun run, but it's a cause close to my heart," Breen said.

"We'll catch up for our regular Sunday night dinner afterwards ... family is a big part of my life and they've given me so much support to chase my goals."

Breen hasn't raced at competition events since the start of the year, but is expected to make her comeback in October or November.

She has one eye on making the Commonwealth Games final on the Gold Coast before testing herself in the US for the first time in her career.

"I didn't think I'd have a chance to race at a home Commonwealth Games, so to be chasing that is something words can't describe," Breen said.

"I've always wanted to compete in America as well, so we haven't locked in any plans yet but because of the Commonwealth Games timing, it opens up the rest of the year.

"It's been a big training block, but I am fit and the body is handling it so I'm getting that itch back to race again."

It is hoped The Canberra Times will raise $125,000 for more than 250 charities. There will be 14 kilometre, 10 kilometre and 5 kilometre races, with all events finishing at Rond Terrace.

CANBERRA TIMES FUN RUN

How to get there

The 14km and 10km start lines are on Yamba Drive near Launceston Street, while the 5km starts on King George Terrace in front of Old Parliament House. But all events end up at the finish line on Rond Terrace along Lake Burley Griffin.

Those in the 5km event can jump on the shuttle bus from Rond Terraces, Commonwealth Park. If you're sticking it out for the 14km and 10km, head to Parkes Place West in Parkes to catch your bus.

Buses run from 10am until noon. Don't worry - there will also be shuttle buses operating from the finish line to take you back after putting in the hard yards.

Where to drop your gear

If you're in the 5km run, head to gear collection at the event village on Rond Terrace. Just make sure you're back at that line on King George Terrace before your 9:30am start.

Those taking on the 14km or 10km runs can drop their things off between 7:15am and 8:10am at the finish area on Rond Terraces.

It's recommended runners arrive at the start area at least 30 minutes before the starting gun goes off.

Where to park

For the 5km race, head to the National Library car park, or the Treasure building. There are also open car parks at the John Gordon building and Parkes Place West.

Those heading out for the 14km or 10km should head to the Hellenic Club for spots.

Or, if you're looking to tuck into some food at the event village, try Anzac Park east or at the CIT car park.

What the weather will be doing

After a low of four, Sunday is warming up to a blustery 19 degrees. But, expect a few showers to cap off the day.

There's a 70 per cent chance of a downpour during the evening. Of course, many runners will be safe and warm in the pub by then!

Which roads will be closed

For those driving rather than running, expect a few detours throughout the first half of the day. Areas affected include Parkes, Phillip, Curtin, Yarralumla and Capital Hill.

From 6am until 1 pm, there will be closures on the northbound lanes of Kings Avenue and Wendouree Drive between Constitution Avenue and Kings Avenue.

Road closures for the 2017 Canberra Times Fun Run. Photo: Canberra Times Fun Run

From 6am until noon, the following road closures will be in place:

Yamba Drive, northbound lanes between Kitchener Street and Yarra Glen
Yarra Glen, northbound lanes
Yarra Glen, southbound lanes between Carruthers Street and Melrose Drive
Melrose Drive, between Theodore Drive and Yarra Glen
Launceston Street, between Easty Street and Yamba Drive
Adelaide Avenue, northbound lanes
State Circle, northbound lanes
Parliament Drive, at the entrance to State Circle and Commonwealth Avenue
Federation Mall, between Queen Victoria Crescent and Parliament Drive
Walpole Crescent, between Queen Victoria Terrace and King George Terrace
Queen Victoria Terrace, between Walpole Street and Langton Crescent
Langton Crescent, between King George Terrace and Queen Victoria Terrace
King George Terrace, between Langton Crescent and Kings Avenue.

Intersections impacted by these closures include:

Yarra Glen with Caruthers Street and Cotter Road
Wisdom Street with Yamba Drive
Adelaide Avenue with Novar Street, Hopetoun Circuit and Empire Circuit
State Circle with Perth Avenue, Rhodes Place, Flynn Drive, Commonwealth Avenue and Kings Avenue
Kings Avenue with Walpole Crescent, King George Terrace, King Edward Terrace, National Circuit, Macquarie Street, Blackall Street and Bowman Drive.

Barriers as well as warning and diversion signs will be in place.

For information on changes to Transport Canberra bus routes visit www.transport.act.gov.au.