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This is Scientific American's 60-Second Science. I'm Steve Mirsky . Got a minute ?

Athletes have obviously been tempted¹ to use performance enhancing anabolic steroids. Drug testing may discourage such use. But a new study finds that some of the performance benefits of steroid use may persist years after an athlete stops doping. That’s according to research presented this week at a conference of the American Physiological² Society.

Swedish scientists looked at power lifters, a pure strength sport. Steroids can increase muscle fiber³ size and the number of cell nuclei⁴ in the fiber. The researchers found that even years after steroid withdrawal—and with little or no current strength training—muscle fiber density⁵ and increased number of cell nuclei were comparable to drug-free athletes currently doing high-intensity strength-training. The additional cell nuclei could give a big advantage to former dopers—more nuclei means more protein synthesis, which means more muscle. So steroid use can still offer a competitive advantage years later. Which means that a clean ballplayer can still hit a dirty home run.

Thanks for the minute for Scientific American's 60-Second Science. I'm Steve Mirsky .