Knee-length compression socks have become a common sight at marathons, with advocates claiming benefits ranging from improved blood f low during the race to more rapid recovery from post-race muscle soreness. Research on these benefits has produced mixed results, but the newest study, also presented at this year’s acsm conference, isn’t encouraging. Scientists split 20 runners at the Hartford Marathon into two groups, with half assigned to wear knee-length compression socks during the race. There were no significant differences between the two groups in finishing time or in levels of creatine kinase, a blood marker of muscle damage, measured immediately after the race or 2 4 hours later. This won’t be the final word on the compression socks debate, but it’s another hint that compression isn’t a miracle cure for marathon-induced soreness.