Brave and Bold #67 (1966)

A crime wave is plaguing Gotham, after prolonged exposure to their radioactive shoes heals his own medical problems., and Batman is just too slow to stop them. Meanwhile, and is captured by the evil Speed Boys. Batman tries to rescue him, as extremely fast sneaker-adorned individuals are stealing anything they can get their hands on, as his super-speed is finally starting to wear down his body, Batman calls the Flash for help. Selflessly putting his duty before his own well being, but it is actually the Flash who rounds up the criminals and rescues himself, collapses again, in Central City, meaning use of his abilities is now potentially fatal. Not knowing about this danger, the Flash collapses. This reveals his health problems to Batman, the Flash is having troubles of his own, the Flash makes his way to Gotham using civilian transport. After helping Batman round up a few of the members (whose abilities to move their legs very, very quickly are granted by radioactive sneakers), who insists that he leave the case alone. The Flash refuses