CLEVELAND -- More than 15,500 people have registered for a free three-month membership program in the Cleveland area.

Of those 15,500 people, about 4,500 have completed registration in person at a Curves or YMCA branch, according to local media reports.

The offer, part of the go!FIT Greater Cleveland Challenge 2010 program sponsored by the Cleveland Clinic, began Jan. 1 and is open to residents of Cuyahoga County (OH) who are not already members of the YMCA or Curves.

Participants in the program must do an initial in-person assessment. They also must commit to working out three times a week and participate in weekly, as well as monthly, weigh-ins.

The sponsors of the program do not check the financial status of the registrants, according to the Cleveland Plain Dealer. Enrollees must not have been involved with another gym in the previous 90 days, according to the newspaper.

The Cleveland Clinic plans to track the overall progress of the participants while keeping their information private, the newspaper reported.