03/03/2011 12:53 pm ET | Updated May 25, 2011

Chicago Marathon Sold Out: Registration Sells Out In Record 31 Days

There is still time for runners to train for the annual Bank of America Chicago Marathon--but those who haven't registered should start looking into a charity to align themselves with, since the race sold out in a record 31 days.

The race, which is on October 9, hit 45,000 registered participants Thursday morning, according to the Chicago Sun-Times. The registration is now closed.

As Bloomberg reports, the Chicago Marathon attracts people from all over the world due to its flat terrain and cooler temperatures, which helps runners set speed records.

Those interested in the 26.2 mile race can still get involved by registering through a charity. Chicago Now's Cubicle Dad reports that the marathon's charity partnerships have generated about $60 million for various causes since 2002.

The charities involved with the race set fundraising minimums that runners must meet in order to participate. In exchange for helping raise these funds, runners often receive training assistance, gear check and the positive vibes that come with helping a good cause. Minimum fundraising amounts range from $400 (the Chicago Diabetes Project) to $1500 (The American Heart Association).

Click here for a full list of participating charities, and to learn about the perks that come with registering through them.

"The record rate of registration is a tribute to the 34-year tradition of our event, as well as to our partners in the community, the City of Chicago and our sponsors who lend their support and resources in helping us produce a wonderful experience for our participants year after year," Executive Race Director Carey Pinkowski told the Sun-Times. "We look forward to welcoming the class of 2011 to Chicago on October 9."