Fight Outcomes In Mixed Martial Arts (mma) From 1991-2021: An Analysis Of 107,227 Competitions

Abstract

Although MMA rules and regulations are similar around the world, they can vary by state, country, and organization. State athletic commissions sanction US-based events, while a governing body of the host nation typically sanctions international events. Accordingly, MMA athletes may have a differential injury risk based on where they fight or the organization for whom they fight. PURPOSE: To determine the distribution of fight outcomes, if outcome distribution varies among US and international organizations, and if major rule changes in US-based organizations have changed the distribution of fight outcomes. METHODS: We extracted data from the ESPN MMA database for fights that occurred between September 1991 and October 2021, capturing 115,512 fights. Fights that did not have a time (7045), round number (147), had rounds greater than five min (1091), or had more than five rounds (2) were removed, leaving 107,227 fights for analysis. When comparing organizations, we used four US (UFC, Bellator, Strikeforce, Invicta) and six international (ONE, Pride, Rizin, Pancrase, M-1 Global, Fight Night) organizations (30,510) and three US-based organizations when comparing pre- and post-adoption of the Unified Rules of MMA (UFC, Bellator, Strikeforce; 18,238). RESULTS: Fights were stopped due to submission (32.5%) or ended in decision (30.5%) most frequently, with knockout (6.3%), technical KO (19.0%), and KO/TKO (9.9%) comprising 35.2% of fight stoppages. When comparing US and international organizations, US fights were more likely to go to Decision (43.6% vs. 38.8%) or end in KO/TKO (23.8% vs. 17.6%), while international organizations had higher rates of Submission (24.6% vs. 21.9%), TKO (12% vs. 6.3%), and KO (3.2% vs. 2.0%). When comparing outcomes pre- and post-Unified Rules, we identified a 51.3% increase in the proportion of fights going to decision and a reduction in the proportion of fights ending in KO/TKO (33.3%) or Submission (28.4%), respectively. CONCLUSIONS: Despite varying rules and regulations across organizations and locations, historical MMA fight outcomes have been similar for US and international competition. Furthermore, implementation of the Unified Rules by US-based organizations is associated with a lower proportion of fights ending by KO/TKO, implying a positive impact on MMA athlete safety.