Mental health, depression, anxiety and psychological stress

Studies that measured mood, depressive symptoms, anxiety and resilience in boxers, kickboxers, MMA fighters and mixed groups of fighters from several combat sports.

Research information, not medical advice. This page does not diagnose, screen or clear anyone to compete.

Most of the studies below are questionnaire studies of one group at one point in time. They show how common a positive screen was in that group and what it was associated with.

The library holds no study of post-traumatic stress disorder in fighters. One source on this page covers a wider group than fighters: a cohort of retired athletes from several contact sports, with former amateur boxers as one subgroup. It is labeled as such below.

What the sources report

  1. Depression, cognition and brain volume in professional boxers

    Lee et al., 2019. Journal of Head Trauma Rehabilitation.

    Article type
    Cross-sectional study with longitudinal subgroup
    Studied
    205 male professional boxers; longitudinal subgroup of 45.
    Status
    Published in a peer-reviewed journal
    • Among 205 male professional boxers, clinically significant depression on the PHQ-9 was associated with smaller volumes in several brain regions and with poorer verbal memory and psychomotor speed.
    • In a subgroup of 45 boxers followed for one to six years, baseline depression was associated with poorer psychomotor speed and reaction time over time. The authors describe the longitudinal evidence as preliminary.

    Full recordDOI 10.1097/htr.0000000000000495

  2. Self-efficacy and depression in boxers

    Chen et al., 2020. Frontiers in Psychiatry.

    Article type
    Cross-sectional questionnaire study
    Studied
    231 Chinese boxers (144 men, 87 women), average age about 20.
    Status
    Published in a peer-reviewed journal
    • The boxers completed three questionnaires: one on confidence in their own ability as athletes (self-efficacy), one on self-control, and one that screens for depressive symptoms.
    • Boxers with higher self-efficacy and self-control scores reported fewer depressive symptoms.
    • In the authors' statistical model, self-control accounted for part of the link between self-efficacy and depressive symptoms.

    Full recordDOI 10.3389/fpsyt.2020.00791

  3. Mental health symptoms in current and former elite kickboxers

    Bilgoe et al., 2025. Discover Mental Health.

    Article type
    Cross-sectional survey
    Studied
    45 current and 29 former elite kickboxers.
    Status
    Published in a peer-reviewed journal
    • 45 current and 29 former elite kickboxers answered screening questionnaires from the International Olympic Committee Sport Mental Health Assessment Tool 1.
    • Among current kickboxers, the most common positive screens were disordered eating (63%) and psychological distress (57%). Among former kickboxers, they were alcohol misuse (43%) and psychological distress (36%).
    • No statistically significant association was found between mental health symptoms and severe musculoskeletal injuries or concussions.

    Full recordDOI 10.1007/s44192-025-00328-w

  4. Depression and resilience in youth MMA athletes

    Fujimoto et al., 2026. Cureus.

    Article type
    Cross-sectional questionnaire study
    Studied
    108 complete survey responses from MMA athletes aged 8–17.
    Status
    Published in a peer-reviewed journal
    • 276 athletes aged 8 to 17 were recruited and 108 completed both questionnaires (39%).
    • 4 of the 108 (3.7%) screened positive for depression at the questionnaire cutoff used.
    • Scores did not differ significantly by age, gender, race, training hours, weight-cutting practices, parental coaching, injury history or years of competition.

    Full recordDOI 10.7759/cureus.101625

  5. Competition anxiety and mental toughness in combat sports

    Mojtahedi et al., 2023. Behavioral Sciences.

    Article type
    Cross-sectional survey
    Studied
    194 combat-sport athletes.
    Status
    Published in a peer-reviewed journal
    • 194 combat sports athletes completed questionnaires and reported their competition anxiety from memory.
    • Athletes reporting greater mental toughness reported lower cognitive and somatic anxiety and higher self-confidence before competition.
    • Athletes endorsing more respectful and altruistic attitudes in sport reported higher competition anxiety.

    Full recordDOI 10.3390/bs13090713

  6. Mood responses during COVID-19 among boxers and coaches

    Roberts et al., 2021. Frontiers in Psychology.

    Article type
    Mixed-method questionnaire study
    Studied
    44 boxers and 14 coaches.
    Status
    Published in a peer-reviewed journal
    • 44 boxers and 14 boxing coaches took part during the first COVID-19 lockdown in the United Kingdom. Boxers rated their mood during lockdown and, from memory, their mood before it.
    • Boxers reported a large increase in anger, confusion, depression, fatigue and tension, and lower vigor, during lockdown.
    • Close contact between coach and boxer and a sense of progress in training were described as helpful ways to manage mood.

    Full recordDOI 10.3389/fpsyg.2021.624119

  7. Rapid weight loss, resilience and pain sensitivity in kickboxers

    Çağlar et al., 2025. Frontiers in Psychology.

    Article type
    Before-and-after observational study
    Studied
    37 elite male kickboxers.
    Status
    Published in a peer-reviewed journal
    • 37 elite male kickboxers were measured before and after a one-month weight-loss period leading up to competition.
    • Pressure-pain thresholds in the thoracolumbar region were lower after the weight-loss period.
    • Four of six resilience subscale scores were higher after the period. Two did not change significantly.

    Full recordDOI 10.3389/fpsyg.2025.1545048

  8. Daytime sleepiness in retired male boxers

    Esagoff et al., 2024. International Review of Psychiatry.

    Article type
    Observational cohort analysis
    Studied
    86 retired male professional boxers.
    Status
    Published in a peer-reviewed journal
    • 86 retired male professional boxers from the Professional Fighters Brain Health Study were included. Mean age was about 51 and the mean Epworth Sleepiness Scale score was 7.5.
    • Higher sleepiness scores were associated with higher impulsiveness scores and higher depression scores in adjusted models.
    • The relationship between number of professional bouts and impulsiveness and depression scores was mediated by sleepiness score.

    Full recordDOI 10.1080/09540261.2024.2364027

  9. Win-loss record, neuropsychiatric symptoms and brain health

    Bryant et al., 2024. The Journal of Neuropsychiatry and Clinical Neurosciences.

    Article type
    Observational professional-fighter cohort analysis
    Studied
    212 professional fighters.
    Status
    Published in a peer-reviewed journal
    • Data from 212 professional fighters in the Professional Fighters Brain Health Study were analysed.
    • Among retired fighters, a better win-loss record was associated with more impulsiveness, slower processing speed and smaller volumes in several brain regions.
    • Fighters with better records did not score better than fighters with worse records on any neuropsychiatric or cognitive test.

    Full recordDOI 10.1176/appi.neuropsych.20230108

  10. Psychiatric features of TES in 20th-century boxing cases

    Iverson et al., 2023. Frontiers in Neurology.

    Article type
    Narrative review of historical clinical case descriptions
    Studied
    155 current and former boxers described in 21 publications from 1928–1999.
    Status
    Published in a peer-reviewed journal

    Scope: Historical case descriptions published between 1928 and 1999.

    • The authors reviewed clinical descriptions of 155 current and former boxers from 21 articles published between 1928 and 1999.
    • A psychiatric, neuropsychiatric or neurobehavioral problem was described in 34.8% of cases. 6.5% of cases were described as primarily psychiatric or neuropsychiatric.
    • Depression was documented in 11.0% of cases, anxiety in 3.9% and suicidality in 0.6%. The authors conclude that these were not considered clinical features of the syndrome in the 20th-century literature.

    Full recordDOI 10.3389/fneur.2023.1214814

  11. Suicide and depression in former contact sports participants

    Batty et al., 2023. eClinicalMedicine.

    Article type
    Population cohort study plus systematic review and meta-analysis
    Studied
    2,004 retired Finnish male international amateur athletes and 1,385 controls; boxing subgroup included.
    Status
    Published in a peer-reviewed journal

    Scope: Broader contact-sports population. The cohort includes former amateur boxers as one subgroup, alongside wrestlers and soccer players. The pooled analysis concerns soccer and American football.

    • 2,004 retired Finnish male athletes who had competed internationally as amateurs and 1,385 general-population controls were linked to hospital and death registries.
    • Former boxers did not have statistically higher rates of major depressive disorder or suicide than controls (depression hazard ratio 1.43, 95% CI 0.73 to 2.78; suicide hazard ratio 1.75, 95% CI 0.64 to 4.38).
    • Seven other cohort studies were pooled with the Finnish data. The pooled results reported in the abstract concern soccer and American football.

    Full recordDOI 10.1016/j.eclinm.2023.102026

Limits of this evidence

  • Screening questionnaires flag symptoms. They do not diagnose a condition.
  • Most samples are small and come from one country, one sport or one cohort.
  • A survey taken once cannot show whether fighting caused the symptoms it measured.
  • In the contact-sports cohort, the estimates for former boxers have wide confidence intervals.

Fight Medicine Research Institute checked each source’s details against PubMed, Crossref, Europe PMC or the publisher. It has not carried out a formal critical appraisal of each paper.