World Series of Boxing Like professional boxing, each bout is decided by the scores of three judges or, in some cases, by a knockout, technical knockout or walk-over. A WSB meet between two international franchises consists of bouts in ten (formerly five) weight categories. There are five three-minute rounds in each bout and the team that wins the most number of bouts wins the meet. Until season 4, there were five weight categories which were different than 10 categories in amateur (Olympic) boxing or 17 categories in professional boxing. These were Heavyweight (91+ kg), Light heavyweight (80–85 kg), Middleweight (68–73 kg), Lightweight (57–61 kg)
Boxing respond that such a position is misguided opinion, stating that amateur boxing is scored solely according to total connecting blows with no award for "injury". They observe that many skilled professional boxers have had rewarding careers without inflicting injury on opponents by accumulating scoring blows and avoiding punches winning rounds scored 10-9 by the 10-point must system, and they note that there are many other sports where concussions are much more prevalent. In 2007, one study of amateur boxers showed that protective headgear did not prevent brain damage, and another found that amateur boxers faced a high risk of brain