2022 年 11 巻 4 号 p. 255-260
Mixed martial arts (MMA) is a combat sport with a high incidence of concussions, including knockouts (KO) due to direct attacks to the head. Once a concussion occurs in a fighter, the rate of concussion recurrence increases. Therefore, participation in matches may be weakened to head impacts as fighters experience repeated concussions. In this study, we investigated the relationship between the occurrence of concussions in male mixed martial arts athletes during the most recent match and their past match records. The analysis included 104 male fighters who competed in elite-level professional MMA competitions. In the most current match, 44 fighters experienced a concussion and 60 fighters did not. Previous KO losses (mean, 2.9) were significantly higher in the fighters who had experienced a concussion compared to fighters who had not (p < 0.0001). Concussion rates (65.0%) were significantly higher in fighters with three or more previous KO losses compared with the rates for fighters with less than 3 previous KO losses (p = 0.03). The odds ratio for the occurrence of concussions in fighters with a history of KO losses was 2.3 times that of fighters without a history of KO losses (p = 0.004). Fighters who had competed in more than 30 matches had a significantly higher incidence of concussions (60.8%) than fighters who had competed in less than 30 matches (37.0%) (p = 0.04). The occurrence of concussions in male MMA fighters is related to the number of previous KO losses and the number of matches.