In brief:One reason behind coaches' prohibitions of sexual activity before sports events may be the belief that abstinence increases frustration, which in turn is displaced into aggressive behavior toward competitors. However, this hypothesis is not always valid. In fact, depriving an athlete of a normal activity may cause guilt and a loss in concentration. Sexual activity throughout training may promote relaxation and positively affect performance. The author concludes that although there is a need for scientific research in this area, it seems that intercourse does not decrease performance unless it is accompanied by late-night socializing, sleep loss, or drinking.