On a chilly November morning, marathon runners know they must dress in layers to keep warm before the 26.2 mile race. But once the gun sounds off and the thousands of runners shed their jackets, sweatshirts, and gloves, what happens to all of that clothing?

That is the question Michael Resnic and his daughter Madeline asked six years ago after watching a Philadelphia road race on the Benjamin Franklin Parkway.

Since then, the father-daughter duo has been collecting runners' discarded clothes from the Philadelphia Marathon and other races around the region in order to donate them to local shelters through their organization clothes-pin.org.

Watch the video above as volunteers from clothes-pin.org collect thousands of pounds of clothing and running gear after the start of Sunday's race.