Long-Term Cognitive Decline in MMA Fighters: A Two-Year Cohort Study on Executive Function Impairments Due to Repetitive Head Strikes
Abstract
1. Introduction
2. Materials and Methods
2.1. Study Design
2.2. Participants’ Characteristics and Baseline Measures
2.3. Training Structure and Head Impact Exposure
2.4. Cognitive Measures
2.5. Statistical Analysis
3. Results
3.1. Mental Processing Speed (MPS)
3.2. Inhibitory Control (IC)
3.3. Cognitive Flexibility (CF)
3.4. Automatic Processes (AP)
3.5. Controlled Processes (CP)
3.6. Direct Memory (DM) and Indirect Memory (IM)
4. Discussion
Practical Applications
5. Conclusions
Author Contributions
Funding
Institutional Review Board Statement
Informed Consent Statement
Data Availability Statement
Acknowledgments
Conflicts of Interest
References
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Monday | Tuesday | Wednesday | Thursday | Friday | Saturday |
---|---|---|---|---|---|
Competitive group morning | |||||
Grappling (≈120 min) | Sparring (≈60 min) | Grappling (≈120 min) | Sparring (≈60 min) | Grappling (≈120 min) | MMA (≈120 min) |
Competitive group evening | |||||
Striking (≈120 min) | - | Striking (≈120 min) | - | Striking (≈120 min) | - |
Recreative group evening | |||||
Striking (≈120 min) | Grappling (≈120 min) | Striking (≈120 min) | Grappling (≈120 min) | Striking (≈120 min) | MMA (≈120 min) |
Measure | CG | RG | Statistics (Tcalc.; p; CI 95%) | ES |
---|---|---|---|---|
Age (yrs.) | 26.7 ± 3.7 * | 32.0 ± 8.2 | T = −2.99; p = 0.004; −5.3 (−8.8; −1.7) | 0.8 |
Weight (kg) | 72.0 ± 8.4 * | 78.7 ± 8.2 | T = −2.92; p = 0.005; −6.7 (−11.4; −2.1) | 0.8 |
Height (cm) | 170.0 ± 0.1 | 1.7 ± 0.1 | T = −0.149; p = 0.88; −0.0 (−0.0; 0.0) | 0.1 |
Practice time (months) | 47.8 ± 5.2 | 46.9 ± 5.0 | T = −0.665; p = 0.5; 0.9 (−1.8; 3.7) | 0.2 |
Sessions per week | 9.7 ± 2.5 * | 4.7 ± 1.1 | T = 9.26; p ≤ 0.001; 5.0 (3.9; 6.1) | 2.6 |
Training duration (min) | 101.5 ± 28.2 | 97.2 ± 28.5 | T = 0.55; p = 0.58; 4.3 (−11.5; 20.1) | 0.2 |
Blows received to the head/ses. | 15.0 ± 1.6 * | 2.4 ± 1.4 # | T = 30.6; p ≤ 0.001; 12.6 (11.8; 13.4) | 8.4 |
Sleep (hours) | 7.4 ± 1.0 * | 6.6 ± 1.0 | T = 3.09; p = 0.003; 0.9 (0.3; 1.4) | 0.8 |
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de Brito, M.A.; Raimundo Fernandes, J.; Ferreira Costa, K.; Maurício, C.A.; Ferreira Gonçalves, A.; de Toledo Nóbrega, O.; Aedo-Muñhoz, E.; Brito, C.J.; Pérez, D.I.V.; Miarka, B. Long-Term Cognitive Decline in MMA Fighters: A Two-Year Cohort Study on Executive Function Impairments Due to Repetitive Head Strikes. Int. J. Environ. Res. Public Health 2025, 22, 1004. https://doi.org/10.3390/ijerph22071004
de Brito MA, Raimundo Fernandes J, Ferreira Costa K, Maurício CA, Ferreira Gonçalves A, de Toledo Nóbrega O, Aedo-Muñhoz E, Brito CJ, Pérez DIV, Miarka B. Long-Term Cognitive Decline in MMA Fighters: A Two-Year Cohort Study on Executive Function Impairments Due to Repetitive Head Strikes. International Journal of Environmental Research and Public Health. 2025; 22(7):1004. https://doi.org/10.3390/ijerph22071004
Chicago/Turabian Stylede Brito, Michele Andrade, José Raimundo Fernandes, Keveenrick Ferreira Costa, Clóvis Albuquerque Maurício, Aleksandro Ferreira Gonçalves, Otávio de Toledo Nóbrega, Esteban Aedo-Muñhoz, Ciro José Brito, Diego Ignácio Vanezuela Pérez, and Bianca Miarka. 2025. "Long-Term Cognitive Decline in MMA Fighters: A Two-Year Cohort Study on Executive Function Impairments Due to Repetitive Head Strikes" International Journal of Environmental Research and Public Health 22, no. 7: 1004. https://doi.org/10.3390/ijerph22071004
APA Stylede Brito, M. A., Raimundo Fernandes, J., Ferreira Costa, K., Maurício, C. A., Ferreira Gonçalves, A., de Toledo Nóbrega, O., Aedo-Muñhoz, E., Brito, C. J., Pérez, D. I. V., & Miarka, B. (2025). Long-Term Cognitive Decline in MMA Fighters: A Two-Year Cohort Study on Executive Function Impairments Due to Repetitive Head Strikes. International Journal of Environmental Research and Public Health, 22(7), 1004. https://doi.org/10.3390/ijerph22071004