Soccer, or football as it is known in most of the world, is without question the world's most popular sport. More people are involved with soccer, as players or spectators, than any other sport. However, to ensure a fair match, soccer balls must conform to certain standards.
FIFA and Soccer
FIFA, The Fédération Internationale de Football Association, the organization behind the World Cup, soccer's highest-level championship, is responsible for regulating the balls used in the game. According to the FIFA website, only balls that meet FIFA's stringent requirements are allowed in the all FIFA-overseen soccer matches, such as the games comprising the World Cup.
FIFA-approved soccer balls come in two sizes, size 4 and size 5, according to FIFA's specification chart. Players older than 12 years of age use size 5 balls, while players aged 8 to 12 years use size 4 balls, according to Soccer Ball World. FIFA regulations state size 5 balls must weigh between 420 g and 450 g, while size 4 balls must weigh between 350 g and 390 g.
Affect on Play
A properly weighted ball ensures a fair and enjoyable match. The average kicked speed of a 230 g soccer ball is about 25 meters per second, according to The Physics Factbook. Players accustomed to this speed, and accustomed to adjusting their kick force to account for it, would not be able to score goals as easily using a lighter or heavier ball.
Factors Affecting Ball Weight
Multiple factors influence ball weight, which is why FIFA has established regulations governing them. For example, FIFA regulates air pressure, the amount of air pressure balls are allowed to lose during play, and even how much water a ball may absorb during play. Size 4 and 5 balls must be pressurized to 0.8 bar, may not lose more than 20 percent of their air pressure and may absorb no more than 25 percent of their weight in water.