Elite athletes are characterized by their high level of performance in sport. Since the very beginnings of sport, it has been understood that physical and physiological abilities influence the performance of athletes. Advances in scientific knowledge, especially sport psychology and neuroscience, seem to confirm this intuition and consequently it is possible to characterize elite athletes as having an extraordinary combination of physical and mental abilities. Techniques and substances that contribute to enhancing physical characteristics of athletes have also been well known (...) for ages. But it is now possible to make use of other techniques and substances that not only enhance physical abilities but also cognitive capabilities, which seem to require greater consideration given their direct impact on the athlete’s brain. In this article, we examine two such techniques, cognitive enhancers and transcranial stimulators, and highlight the potential advantages and drawbacks that applying each one may have on sport. Given the relative novelty of these enhancement techniques and substances and the absence of conclusive evidence regarding their short- and long-term effects, we deem that their use ought to be strictly governed by cautionary principles. But due to that same lack of evidence, we believe that the possibility of examining the feasibility of applying these techniques to sport should not be denied. (shrink)