In 1921, Franklin D. Roosevelt was sailing in the Bay of Fundy when he fell overboard into the cold waters. The next day, he felt weakness in his legs. The sensation intensified, and, soon enough, he could no longer walk. Once doctors sorted things out, F.D.R. discovered that he had contracted polio, a disease that typically afflicted children, not adults. A long and grueling period of rehabilitation followed, mostly in Warm Springs, Georgia. You can see footage of his rehab right below.
With a lot of hard work, F.D.R. learned to walk short distances, aided by leg braces, a cane, and someone's shoulder to lean on. When he re-entered politics, the F.D.R. Presidential Library notes, he "requested that the press avoid photographing him walking, maneuvering, or being transferred from his car. The stipulation was accepted by most reporters and photographers but periodically someone would not comply. The Secret Service was assigned to purposely interfere with anyone who tried to snap a photo of FDR in a 'disabled or weak' state." Above, you can see (according to CNN) only the second known clip that shows F.D.R. walking. (Watch around the 40 second mark.) Recorded in Washington, D.C., at the 1937 All-Star Game, the video was recently donated to the Pennsylvania Historical and Museum Commission. The other extant video appears right below.