Parts of the Don Valley Parkway and Gardiner Expressway were closed Sunday as thousands of people took part in the annual Manulife Heart & Stroke Ride for Heart.

Organizers said about 12,000 cyclists and about 2,000 walkers joined the 32nd instalment of the annual event.

Participants were on track to raise more than $5 million, an amount that will be used to fund heart disease and stroke research and policy changes to benefit cardiovascular health, organizers said. Since it began in 1988, the ride has raised $70 million.

The 75 kilometre ride began at 6 a.m., while the 50 kilometre and 25 kilometre rides started at 7 a.m. The five kilometre walk got underway at 10 a.m.

Organizers said about 12,000 people are cycling and about 2,000 people are walking in the 32nd annual Manulife Heart & Stroke Ride for Heart. (Spencer Gallichan-Lowe/CBC)

Yves Savoie, CEO of the Heart and Stroke Foundation, said thousands of people turned out on a cloudy day for a good cause. Nine out of 10 Canadians are at risk of heart disease, he said.

"It touches us all at the end of the day," Savoie said.

Bailey Bernknopf, a "child survivor ambassador" for the foundation, said she was "amazed" by the turnout. She was diagnosed with four congenital heart defects at five months of age and has had two heart surgeries to repair them.

"It's very humbling to see everybody out here fundraising for one cause that means so much to me," she said.

Bernknopf is also a University of Toronto masters student at the Ted Rogers Centre for Heart Research, studying sex differences in aortic valve disease.

Participants are on track to raise more than $5 million, an amount that will be used to fund heart disease and stroke research and policy changes to benefit heart health. (Spencer Gallichan-Lowe/CBC)

For Dr. Craig Simmons, a University of Toronto professor and researcher at the Ted Rogers Centre of Heart Research, the ride was a "great opportunity for us to give back" because his lab is funded by the foundation.

The lab is trying to come up with cures for heart disease and heart valve disease. Bernknopf is one of his students.

The event is also "a good time and exercise" and enables participants to "do our hearts well," he said.

"These fundraising events are essential for medical research. The Heart and Stroke Foundation has funded millions and millions of dollars over the years toward heart research. That research then results in advancements and new treatments and improvements to heart health," he added.

"Without fundraisers like this, we couldn't do the work we continue to do."

DVP, Gardiner closed until 3 p.m.

Both the Don Valley Parkway and Gardiner Expressway were closed until 3 p.m. in both directions.

Toronto police said the Don Valley Parkway was closed from Gardiner Expressway to York Mills Road, while the Gardiner Expressway was closed from the South Kingsway to the Don Valley Parkway.

Motorists were told to expect road closures in the area surrounding Exhibition Place as well.