In brief:Participation in soccer is increasing, possibly because many people believe that anyone can play the game. This article reviews the nature and demands of soccer and the physiological characteristics of the players, including aerobic power, anaerobic power, muscle strength, flexibility, agility, glycogen use, and fiber types. Soccer players must perform short sprints as well as cover long distances during a game. Soccer players fall in the middle of the ranges for athletes in all of the measured variables. The author concludes that soccer players are unique in their ability to repeatedly perform difficult motor skills during constantly changing tactical situations.