"Race for the cure:" How would running cure diseases?

I hear so much about these “races for the cure:” events where a bunch of people get together and run, bike, rollerblade or whatever in pursuit of the cure to some dread disease or other. It’s all well and good that people out there are making the effort, but how does group exercise bring us any closer to curing, say, colitis?

I understand, based on walkathon participation as a tot, that sometimes a donor pledges a certain amount of money per mile/kilometer covered. This, of course, begs the question: Why do people have to run for the donation to go through?

Psychology. People are more likely to donate if it appears that the solicitor is going to demonstrate his or her commitment to the cause through some overt action. It also gives the participants a concrete event around which they can rally their commitment and their energies.

I’ve been involved in such fundraising attempts before. These things are a lot more effective than merely asking people to solicit money from their friends.

Large charity runs also attract media attention, which draws public notice to the cause promoted. More public attention means more donations and a greater lobby to press for government funding.