Antisocial, narcissistic personality traits and symptoms of attention deficit hyperactivity disorder in combat athletes

Abstract

Background

This study aimed to compare antisocial, narcissistic, and Machiavellian traits, along with attention-deficit/hyperactivity disorder (ADHD) symptoms and psychiatric history, between combat athletes and non-athletes.

Method

In this cross-sectional study, a total of 300 participants (150 combat athletes and 150 non-athletic controls) completed online assessments. The Sociodemographic and Clinical Data Form, Adult ADHD Self-Report Scale, Narcissistic Personality Inventory, Antisocial Behaviour Scale, and Machiavellianism Scale were administered. Group comparisons were performed using appropriate statistical tests.

Results

Combat athletes demonstrated significantly higher scores on the Antisocial Behaviour Scale (27.4 ± 6.3 vs. 21.1 ± 5.9; p < 0.001), Narcissistic Personality Inventory (17.6 ± 4.8 vs. 13.2 ± 4.5; p < 0.001), and Machiavellianism Scale (41.3 ± 7.1 vs. 36.0 ± 6.4; p < 0.001). ADHD symptom scores were descriptively higher in combat athletes (31.9 ± 9.2 vs. 25.5 ± 8.6; p < 0.001); however, ADHD symptoms did not remain an independent predictor in the multivariable model. In addition, psychiatric diagnoses, medication use, self-harm behaviors, and suicide attempts were more prevalent among combat athletes.

Conclusion

Individuals engaged in combat sports exhibited higher levels of antisocial, narcissistic, and Machiavellian traits, along with descriptively elevated ADHD symptomatology and psychiatric vulnerability. However, ADHD symptoms did not show an independent predictive signal in adjusted models, whereas narcissistic traits emerged as the most robust independent correlate of combat sports participation. These findings highlight the importance of targeted mental health screening and intervention strategies in this population.

Supplementary Information

The online version contains supplementary material available at https://doi.org/10.1186/s40359-026-05176-z.

Introduction

Combat sports, which derive from primal human instincts of competition and dominance, have been developed into formal systems where not only physical power but also mental endurance is required. Athletes are subjected to high training loads, stringent routines and performance requirements, which can interact with individual predispositions and mental health status [1, 2]. Although involvement in combat sports has been related to positive consequences, like increased self-discipline, confidence, and emotional control, it can also appeal to or exacerbate some negative elements related to aggression and power in relationships [3, 4]. Nevertheless, the nature of the relationship is still considered controversial by the literature. In essence, the self-selection hypothesis holds that individuals with certain personality predispositions are attracted to combat sports, whereas the socialization hypothesis holds that engagement in these activities has the potential to (further) actively mould such characteristics [5, 6]. In this vein, the “Dark Triad” (i.e., co-occurrence of antisocial aspects, narcissism, and Machiavellianism) of personality has gained surprising sport psychology research attention. These features are associated with reduced levels of empathy, they exploit other people and they have a strong sense of self which could be compatible with the combative nature of competitive combat sports [5–7]. Two contrasting theoretical stances can be held with respect to this relationship. The antisocial, narcissistic and Machiavellian individuals prefer competition-based and more aggressive combat sports, according to the self-selection hypothesis. The socialization hypothesis, on the other hand, suggests that such traits may be reinforced or amplified through participation in these sports due to the repeated exposure to dominance driven interactions and norm compliant aggression [8, 9].

Prior research results have been inconsistent. In contrast to Vaughan et al. (2019) who found higher Dark Triad traits in contact sport athletes versus non-sport athletes, other research demonstrates no differences after controlling for demographic variables or that the relationship is moderated by level of competition [10, 11]. In addition, the majority of research has evaluated singular traits rather than the entire Dark Triad configuration at once. There is emerging evidence that features of ADHD symptomatology, empathy deficits and narcissistic pathology may have transdiagnostic overlap that transcends strict diagnostic classifications [12].

Along with personality traits, ADHD symptoms constitute a further critical yet unexamined aspect. Adult ADHD, characterised by impulsivity, inattention and emotional dysregulation, is estimated to affect between 2.5 and 5% of the adult population and has been associated with both risk-taking behaviour and failures in structured environments [13, 14]. The association between ADHD and sports is multifaceted: organized physical activity has been demonstrated to enhance executive functions and reduce impulsivity in children with ADHD [15, 16], however, research in adult subjects, especially in those practicing high contact sports, is very limited. Given the nature of the high-contact sport—rapid sequences requiring precise timing and inhibition of mistakes, coupled with aggressive movement and physical contact with the opponent, combat sports may especially appeal to those with ADHD symptoms or represent a corrective environment. So far, research systematically assessing ADHD symptom severity in combat athletes versus non-athletic controls is sparse, and results have been mixed [9, 10].

There has been increasing interest, but studies examining both Dark Triad and ADHD traits in a single model are still scarce. Furthermore, most of the research is based on small or culturally homogeneous samples and is not inclusive of widespread comparisons with non-athletes, consequently limiting the applicability of the results. To fill these gaps, the present study adopts a comparative cross-sectional design and hypothesis-driven approach, and applies structural equation modeling (SEM) as an exploratory analytical tool to assess the complex associations among gender, childhood physical abuse, Dark Triad traits, and combat sports participation. In particular, we investigate whether combat athletes obtain higher scores than non-athletes in antisocial behavior, narcissism, Machiavellianism, and ADHD symptoms while controlling for relevant sociodemographic covariates.

Methods

Study design

This study used a quantitative, cross-sectional, comparative survey design. Between June 15 and August 15, 2024, data were collected online. Eligible participants provided electronic consent and completed the self-reported online surveys. The participants comprised individuals who engaged in combat sports and a control group. The forms were distributed through email, WhatsApp and Telegram, allowing the respondents to take the assessments on their own gadgets and facilitating the gathering of data from various geographical locations. Using Google Forms, the online survey was divided into five sections and included 111 items, including an introductory sociodemographic form along with four psychometric scales. It took about 15 to 20 min to complete. All questions were set as required for the key variables of the main study, and therefore the respondents were not able to submit the form with incomplete answers on the core measures. There was no formal pilot study; however, the survey was pilot tested for clarity, functionality, and technical feasibility by the research team before the commencement of data collection. No monetary or academic credits were given as reward for the participation. To avoid multiple entries, the “one response per user” option was selected from Google Forms and participants were allowed to submit only once. The link for the survey was sent to the group (via e-mail, WhatsApp and Telegram) with a standard invitation letter stating the purpose of the study, voluntary nature of participation, anonymity, and approximate time needed to complete it. Since an open-link distribution method was employed, the numbers of individuals reached and a formal response rate could not be calculated, and this is acknowledged as a limitation.

Sample and population

A total of 340 individuals were surveyed for eligibility. Of these, 40 were not in the final analysis due to the following reasons: missing data on main study variables (n = 22), not fulfilling the inclusion criteria (n = 11) or withdrawal of consent (n = 7). In the final analysis, full and valid information was available from 300 participants. The remaining 300 participants were considered eligible and were subsequently allocated into two groups based on their combat sports participation status: 150 individuals with a history of combat sports participation and 150 without such experience, serving as the non-athletic comparison group (Fig. 1). The minimum sample size required was determined in advance using the G*Power software (version 3.1.9.7). With the design of an independent-samples t-test between two groups, performing a two-tailed test with an alpha level of 0.05 and a power of 0.80 and assuming a medium effect size of d = 0.5, the analysis found that a minimum of 64 participants per group (a total of N = 128) were necessary to detect a significant effect. A final sample size of 150 participants per group was larger than this minimum thereby making it sufficient to achieve adequate statistical power for the intended analyses. Recruitment was by convenience sampling and group determination was by self-reported combat sports training. Though there was an attempt at recruiting a demographically similar control group, there are still some statistically significant differences between the groups in age, marital status, and work status (see Table 1). Hence, these variables were regarded as potential confounders and were adjusted for in multivariable models.

Fig. 1.

CONSORT Flowchart of patient selection and inclusion process

Table 1.

Comparison of sociodemographic characteristics between combat sports participants and non-participants ^a

	Combat Sports (n = 150)	Non-Participants (n = 150)	p-value
Age, median [min–max]	31.0 [18–64]	36.0 [18–59]	< 0.001
Gender, n (%)			0.999
- Male	103 (68.7%)	103 (68.7%)
- Female	47 (31.3%)	47 (31.3%)
Marital Status, n (%)			< 0.001
- Single	89 (59.3%)	52 (34.7%)
- Married	61 (40.7%)	98 (65.3%)
Employment Status, n (%)			< 0.001
- Unemployed	11 (7.3%)	2 (1.3%)
- Employed	90 (60.0%)	131 (87.3%)
- Student	44 (29.3%)	14 (9.3%)
- Retired	5 (3.3%)	3 (2.0%)
Monthly Income, n (%)			0.246
- Less than expenses	49 (32.7%)	36 (24.0%)
- Equal to expenses	72 (48.0%)	80 (53.3%)
- More than expenses	29 (19.3%)	34 (22.7%)
Education Level, n (%)			0.055
- Primary	2 (1.3%)	0 (0.0%)
- High School	40 (26.7%)	30 (20.0%)
- Bachelor’s Degree	82 (54.7%)	78 (52.0%)
- Postgraduate	26 (17.3%)	42 (28.0%)

^a: Chi-Square Test was performed

Inclusion and exclusion criteria

Criteria for Inclusion Participants in the combat sports: (1) between 18 and 65 years of age; (2) were able to provide informed consent for themselves via online platforms; (3) were able to read, write and understand Turkish; and (4) were willing to participate in the study voluntarily. Combat sports were considered to be professional individual sports that included a direct physical contact with an adversary by striking, grappling, throwing, or applying submission procedures (e.g., boxing, kickboxing, mixed martial arts, wrestling, judo, karate, taekwondo). Although specific combat modalities were documented for descriptive purposes and not to make comparative (between domain) analyses, the principal reason for the study was not for comparative analysis across domain but to investigate combat sports participation as a physical and psychological exposure in the broadest term. Because some disciplines contained relatively small numbers, meaningful subgroup analyses were not feasible. Therefore, discipline-specific subgroup analyses were not conducted, and the distribution of disciplines is not reported. This decision is further addressed in the Limitations section.

Inclusion Criteria for the Control Group: Aged between 18 and 65 years, Provided informed consent via online platforms, Proficient in reading, writing, and understanding Turkish, Willing to voluntarily participate in the study.

Exclusion Criteria for Both Groups: Under 18 or over 65 years of age, Refusal or inability to complete informed consent, diagnosed with bipolar disorder, Current presentation of psychotic symptoms, Cognitive impairments such as intellectual disability or dementia, diagnosed substance or alcohol use disorder, Inability to read or write, Insufficient Turkish language proficiency, Incomplete responses on scales and forms.

Study hypotheses

• H1: Sociodemographic and clinical characteristics significantly differ between combat sports participants and non-participants.

• H2: The prevalence of antisocial and narcissistic traits is significantly higher among combat sports participants compared to non-participants.

• H3: The frequency of ADHD symptoms is significantly greater among combat sports participants than among non-participants.

• H4: Combat sports participants demonstrate significantly higher Machiavellian traits compared to non-participants.

Instruments

Sociodemographic and Clinical Data Form: A 25-item form developed by the researchers to collect data on age, gender, marital status, education, occupation, income, psychiatric history, and medical background. The form included items on lifetime psychiatric diagnosis and medication use; however, specific diagnostic subtypes (e.g., major depression, anxiety disorders, ADHD, bipolar disorder) were not recorded, as the study focused on overall psychiatric vulnerability rather than specific diagnostic categories. The content was structured according to the study’s scientific objectives. The Sociodemographic and Clinical Data Form was developed by the authors to collect baseline characteristics (see Additional file 1).

Antisocial Behavior Scale (ABS): Developed by Burt and Donnellan, the ABS is a 32-item scale evaluating antisocial tendencies across three dimensions: physical aggression, rule-breaking behavior, and relational aggression. Items are rated on a 5-point Likert scale [17]. The ABS is a 32-item self-report scale evaluating antisocial tendencies across three dimensions: physical aggression (10 items), rule-breaking behavior (11 items), and relational aggression (11 items). Items are rated on a 5-point Likert scale (1 = strongly disagree to 5 = strongly agree), with total scores ranging from 32 to 160. Higher scores indicate greater antisocial tendencies. Internal consistency across multiple validation samples yielded Cronbach’s alpha values between 0.71 and 0.91. The Turkish adaptation by Kılıç et al. was used [18]; in the present sample, Cronbach’s alpha was 0.82 for the total scale.

Narcissistic Personality Inventory (NPI): Originally developed by Raskin and Hall [19], the Turkish adaptation by Atay was used [20]. The NPI consists of 16 forced-choice items where one option reflects narcissistic content. The NPI is a 16-item forced-choice self-report inventory in which respondents select between two statements—one narcissistic and one non-narcissistic. Total scores range from 0 to 16, with higher scores indicating greater narcissistic tendencies. The Turkish adaptation by Atay [20] was used; in the present sample, Cronbach’s alpha was 0.79.

Adult ADHD Self-Report Scale (ASRS): The ASRS is an 18-item self-report scale assessing inattention (9 items) and hyperactivity/impulsivity (9 items), with each item rated on a 5-point Likert scale (0 = never to 4 = very often). Total scores range from 0 to 72, with scores ≥ 24 indicating high probability of ADHD, 17–23 indicating moderate probability, and 0–16 indicating low probability [21]. The Turkish version, validated by Doğan et al. [22], showed good internal consistency (α = 0.82 for inattention; α = 0.78 for hyperactivity). In the present sample, Cronbach’s alpha was 0.81 for the total scale.

Machiavellianism Scale (MACH-IV): The MACH-IV is 20-item self-report scale measuring Machiavellian tendencies, with 10 items reverse-scored. Items are rated on a 5-point Likert scale (1 = strongly disagree to 5 = strongly agree). Total scores range from 20 to 100, with higher scores indicating greater Machiavellian traits. The Turkish adaptation by Bakir et al. [23] was used; in the present sample, Cronbach’s alpha was 0.77.

Ethical considerations

This study was approved by the Academic Board of the Department of Mental Health and Diseases, Faculty of Medicine, “Blinded statement” University (Decision No: “Blinded statement”), and by the Clinical Research Ethics Committee of Mersin University Rectorate (Decision No: “Blinded statement”). All procedures adhered to the Declaration of Helsinki and institutional ethical guidelines.

Participant confidentiality and data privacy were strictly maintained. Data were anonymized, with no collection of personally identifiable information, and each participant was assigned a random code. Informed consent was obtained electronically after participants were briefed on the study’s aims and procedures. All data were used solely for scientific purposes and not shared with third parties.

Statistical Analysis

Descriptive statistics were reported as the mean ± standard deviation (SD) or median (min–max) for continuous variables and n (%) for categorical variables. Normality was tested by the Kolmogorov–Smirnov and Anderson–Darling tests, supported by histograms and normal Q–Q plots. For categorical variables, the comparison between groups was analyzed by using Pearson’s Chi-Square, Fisher’s Exact test or Fisher-Freeman-Halton test when appropriate. Continuous variables with nonnormal distributions were subjected to Mann–Whitney U test, and Spearman’s rho was used to correlate them. Structural equation modeling (SEM) was conducted with WLSMV estimation with Theta parameterization in Mplus 8.3, using chi-square, RMSEA, CFI, and TLI to evaluate model fit. Models were run with 10,000 iterations and a convergence criterion of 0.00005. The candidate variables for inclusion in the logistic regression were decided based on study hypotheses and prior literature on the Dark Triad traits, ADHD symptoms and psychiatric history as related to engagement in combat sports. First, univariate logistic regression analyses were conducted to find the candidate predictors of combat sports. All variables that were significant at p < 0.10 in univariate analyses were entered simultaneously into the multivariable logistic regression model using the enter method. Adjusted odds ratios (ORs) with 95% confidence intervals (CIs) are presented for all variables entered. ADHD symptomatology (ASRS total score) was also originally entered in the univariate analyses; however, it did not hold in the multivariable model (p = 0.095). Model fit was evaluated by Hosmer–Lemeshow test (p = 0.62) and the Nagelkerke R² (0.31). Odds ratios (ORs) are reported with 95% confidence intervals (CIs) and p-values. Descriptive statistics, group differences, and logistic regression were calculated in Jamovi (version 2.3.28) and JASP (version 0.18.3), with key results being cross-validated on the two platforms to check for identical outcomes. Structural equation modeling was performed with Mplus 8.3, because this program has more advanced features for latent variable modeling/mediation analyses with categorical and non-normal data.

Results

The mean age of participants in the martial arts group was significantly lower than that of the control group (p < 0.001). No significant difference was observed between the groups in terms of gender distribution (p = 0.999). However, participants in the martial arts group were significantly more likely to be single (p < 0.001). Additionally, active employment status was more prevalent in the control group, whereas the martial arts group had a higher proportion of students (p < 0.001). No statistically significant difference was observed regarding monthly income or educational level (p > 0.05 for both) (Table 1).

Participants in the martial arts group reported a significantly higher prevalence of grade repetition (p = 0.003), disciplinary penalties (p = 0.021), and emotional abuse or neglect in childhood (p = 0.007) compared to the control group. Rates of physical abuse and bullying did not differ significantly. Furthermore, psychiatric history variables including visiting a psychiatrist (p = 0.001), receiving a psychiatric diagnosis (p < 0.001), and current/past psychotropic medication use (p = 0.002 and p = 0.021, respectively) were all significantly higher among martial arts practitioners (Table 2).

Table 2.

Childhood adversities and psychiatric history by group ^a

	Combat Sports (n = 150)	Non-Participants (n = 150)	p-value
Grade Repetition	39 (26.0%)	18 (12.0%)	0.003
Disciplinary Actions	29 (19.3%)	14 (9.3%)	0.021
Emotional Abuse/Neglect (Childhood)	53 (35.3%)	31 (20.7%)	0.007
Physical Abuse (Childhood)	43 (28.7%)	28 (18.7%)	0.057
Bullying Exposure	61 (40.7%)	55 (36.7%)	0.553
Ever Saw Psychiatrist	60 (40.0%)	33 (22.0%)	0.001
Received Psychiatric Diagnosis	44 (29.3%)	18 (12.0%)	< 0.001
Past Psychiatric Medication Use	58 (38.7%)	32 (21.3%)	0.002
Current Psychiatric Medication Use	25 (16.7%)	11 (7.3%)	0.021

^a: Chi-Square Test was performed

Martial arts practitioners exhibited significantly higher scores on the Antisocial Behavior Scale (p = 0.004), especially in the physical aggression subdimension (p < 0.001). They also had significantly higher total scores on the Narcissistic Personality Inventory (p < 0.001), particularly in authority, exhibitionism, exploitativeness, and superiority subscales. Machiavellianism was also significantly higher in the martial arts group (p = 0.006), with both subscales being significantly different (Table 3).

Table 3.

Psychometric scale scores by group ^a

	Combat Sports (n = 150)	Non-Participants (n = 150)	p-value
Antisocial Behavior Scale (Total)	58.0 [32–152]	54.0 [32–115]	0.004
Physical Aggression	24.0 [10–50]	20.0 [10–45]	< 0.001
Relational Aggression	21.0 [11–51]	20.0 [11–47]	0.176
Rule-Breaking	13.0 [11–51]	13.0 [11–25]	0.126
Narcissistic Personality Inventory	5.0 [0–16]	4.0 [0–12]	< 0.001
- Authority	1.0 [0–2]	0.0 [0–2]	< 0.001
- Exhibitionism	1.0 [0–3]	0.0 [0–3]	< 0.001
- Exploitativeness	1.0 [0–3]	1.0 [0–3]	0.024
- Superiority	1.0 [0–3]	1.0 [0–3]	0.007
Machiavellianism (MACH-IV)	57.0 [34–91]	55.0 [37–77]	0.006

^a: Mann Whitney U-test analysis was conducted and shown as median [min–max]

The martial arts practitioners had significantly higher prevalence of non-suicidal self-injury (p < 0.001), suicide attempts (p = 0.001) and convictions due to impulsive criminal behaviour (p = 0.001). On the other hand, no statistically significant difference between the two groups was found with respect to substance use, problem gambling or problems related to military service (all p values > 0.05) (Table 4).

Table 4.

Risk behaviors and psychiatric outcomes by group ^a

	Combat Sports (n = 150)	Non-Participants (n = 150)	p-value
Self-Harm History	29 (19.3%)	2 (1.3%)	< 0.001
Suicide Attempt	15 (10.0%)	1 (0.7%)	0.001
Legal Issues due to Impulsivity	23 (15.3%)	5 (3.3%)	0.001
Drug Use (ever)	25 (16.7%)	22 (14.7%)	0.754
Gambling Problems	7 (4.7%)	3 (2.0%)	0.335
Alcohol Abuse (Life Impacting)	9 (6.0%)	4 (2.7%)	0.257

^a: Chi-Square Test was performed

Several significant predictors of martial arts participation were found from logistic regression analyses. In the multivariate analysis, being actively employed was still a protective factor (OR = 0.18, p = 0.039) whereas having previously sought psychiatric advice was a risk factor for participation (OR = 2.77, p < 0.001). Childhood emotional neglect, antisocial traits (in particular physical aggression), narcissistic features, and Machiavellianism were all significant predictors in univariate analyses, although only narcissism emerged as a strong independent predictor in the multivariate model (OR = 1.21, p < 0.001). ADHD traits were not significant predictors (p = 0.095) (Table 5).

Table 5.

Multivariable Logistic Regression: Predictors of Combat Sports Participation

	Odds Ratio (95% CI)	p-value
Active Employment	0.18 (0.04–0.85)	0.039
Psychiatric Consultation	2.77 (1.62–4.75)	< 0.001
Narcissistic Personality Inventory (Total)	1.21 (1.10–1.33)	< 0.001
Emotional Abuse/Neglect (Childhood)	1.59 (0.77–3.26)	0.212
Machiavellianism Scale	1.01 (0.94–1.08)	0.875
ADHD Symptoms (ASRS Total Score)	Not retained in model	—

A multivariate binary logistic regression analysis was conducted to identify independent predictors of combat sports participation. All variables that were significant at p < 0.10 in univariate analyses were entered simultaneously into the multivariable model using the enter method. ADHD symptoms (ASRS total score) were initially included in univariate analyses but were not entered into the multivariable model due to lack of statistical significance (p = 0.095). Model fit: Hosmer-Lemeshow χ² = 7.34, p = 0.62; Nagelkerke R² = 0.31. Adjusted odds ratios (ORs) with 95% confidence intervals (CIs) are presented for all entered variables. Odds Ratios (ORs) with 95% Confidence Intervals (CIs) were calculated for each predictor. The enter method was used, and model fit was assessed using the Hosmer–Lemeshow goodness-of-fit test and pseudo-R² statistics

Based on the results of the structural equation modeling analysis, male gender (β = 0.22) and physical abuse (β = 0.21) predicted both direct and indirect participation in combat sport. These influences were particularly mediated by Antisocial Behavior (β = 0.36), Narcissistic Personality Traits (β = 0.44), and Machiavellian Tendencies (β = 0.27). The model fit was satisfactory (χ²/df = 14.23/10, p = 0.162, CFI = 0.978, TLI = 0.956, RMSEA = 0.038). These results are indicative of a particular concern relating to male gender and physical abuse as potential risk factors for greater involvement in combat sports, and suggest that this association may be conceptualised as a manifestation of underlying dark personality traits. Participation in combat sports was related to a social context in which these personality traits could be enacted, and this may be indicative of an attraction toward these sports (Fig. 2).

Fig. 2.

Standardized Structural Equation Model Showing the Direct and Indirect Effects of Gender and Physical Abuse on Combat Sports Participation via Dark Triad Traits (Antisocial Behavior, Narcissism, and Machiavellianism)

Discussion

The present investigation is the first to present a detailed comparison of combat sport athletes and a nonathletic comparison group, with notable differences emerging on a number of sociodemographic, behavioral, and psychological measures.

Among the main results, it was found that participants in combat sport were notably younger than those in the control group. This corroborates the idea that the physical requirements of such activities, e.g., muscular strength, cardiovascular endurance, flexibility, and speed, can be better fulfilled by young people, since they have higher and more modifiable physiological capacities [11]. In addition, young players might simply be more attracted to new, risky, and competitive experiences, which could have made combat sports practitioners higher in that attribute [13, 14].

The predominance of males in the combat sports sample is in line with previous research suggesting the influence of biological and socio-cultural factors. High levels of testosterone in men have been associated with increased aggression, dominant behavior, and competitiveness, which could correlate to their increased participation in physical contact sports [15]. From a cultural perspective, masculinity is linked to being strong and aggressive and participation in combat sports in this sample was linked to higher levels of narcissistic traits and aggression, status need fulfillment, and emotion expression rules navigation congruent with their gender roles [16]. However, an increasing number of women participating - especially in urban centres - has been related to the need for self-defence and changing gender norms that allow women more agency in physical and social spaces [24].

Marital status was also a distinguishing factor; those who were unmarried showed a higher tendency to engage in combat sports. This finding concurs with the literature indicating that the demanding training schedules and injury potential inherent in this type of sport are more readily accepted by people with fewer family and work commitments [25, 26].

Students predominated among combat sport practitioners, suggesting a propensity for younger people not yet fully engaged in working life to participate in physically demanding sports. Higher education provides individuals with more flexible schedules and more peer influence for growth, which they could use as sport as a means of coping with stress, enhancing their self-esteem, and increasing their physical conditioning [27].

The level of education was comparable, suggesting that those who practice combat sports come from different educational backgrounds. This corresponds to findings of Alexander et al. that a common driving and perceived ‘pull’ factor across educational levels amongst martial arts and combat sports is evident [28].

The more frequent grade repetition found in the combat sports group could represent a background of academic frustrations or social alienation with possibly long lasting affective and behavioral implications [29]. Because martial arts promotes self-discipline, control, and emotional regulation, it may represent a different route for these at-risk youth to deal with psychosocial issues and to reconceptualize their personal stories [4, 30]. This is consistent with previous research showing that those who participate in combat sports are more likely to have a history of academic difficulties [31].

Our results also indicate that former combat sport athletes were more likely to have received punitive measures, possibly indicating impulsivity, rule-breaking behavior, or problems with authority. This observation is further supported by the higher levels of antisocial traits found in them. Previous studies demonstrate that impulsivity and antisocial behaviors are robust predictors of rule violations [29].

The equivalence between groups on military service difficulties, however, seems to suggest that at least some aspects of reactions to authority are situation specific. Individuals who participate in combat sports may embody resistance to the “college system” but perhaps this particular brand of institutional authority (military) [32] is more palatable.

Subjects in the combat sports group in the present study also reported greater emotional neglect and abuse. These early adverse experiences are both risk factors for a range of psychopathologies, and may interfere with capacities for secure attachment and emotional regulation. For some such individuals, they may even find the pursuit of combat sports as a way of reclaiming control, of learning to defend themselves, and of resisting psychological shock [32–34]. In conjunction with psychosocial care, martial arts could be used as rehabilitative platforms to facilitate trauma recovery [34]. In addition, the structural equation analysis demonstrated that male sex and physical abuse experience were significant positive predictors of combat sports participation, both directly and indirectly through dark personality traits.

Conversely, no significant differences were found between groups in relation to experiences of physical abuse or peer bullying, suggesting that not all types of childhood adversity are linked to participation in combat sports. Those who have been abused physically may become aggressive but also may be selective about where they become aggressive and those who were bullied by their peers may develop avoidant social behaviors that are at odds with the interpersonal requirements of a combat sports milieu [31].

The much greater utilization of psychiatric services, diagnosis, and medication use in combat sports participants has significant clinical ramifications. While a few persons may practice combat sports oriented towards stress coping, self-esteem building or emotional control, these cross-sectional results cannot be interpreted in the sense that combat sports would offer adequate or protective means of coping. Conversely, a higher prevalence of psychiatric history, self-harm and suicide attempts in participants in combat sports in this sample may indicate that this population is clinically at risk and should be subject to thorough psychological evaluation. The association between combat sports and mental health outcomes is likely to be bidirectional and dependent on contextual factors and thus needs to be explored prospectively [30, 31, 33], in addition to the potential for the strenuous emotional and physical demands to contribute to a worsening of pre-existing vulnerabilities. However, a greater propensity to seek help may also reflect an increased level of insight and a more active attitude towards mental health in this group [4].

The rates of self-harm (19.3%) and suicide attempts (10.0%) were markedly increased in the combat sports athletes in comparison to the non-athletic control group (1.3% and 0.7%, respectively). Although these rates are of clinical concern, comparison with prevalence in the general population of Turkey is hampered by inconsistencies in definitions and instruments, and also age ranges across investigations [12]. For instance lifetime self-injury prevalence in Turkish university samples varies between 15% and 28%, yet methodological dissimilarities prevent direct comparisons [35]. However, the fact that this study revealed a significant difference between groups emphasizes that mental health screening should be a standard feature of combat sport environments. It is possible that this is a consequence of maladaptive coping mechanisms related to narcissistic traits, antisocial or Machiavellian behaviors. Physical forms of violence, including that investigated by Van Hauwermeiren et al. [4], were found to be associated with both self-harm and other-harm. People with narcissistic tendencies can experience emotional breakdown after failure or invalidation, leading to increased risk of self-harm [36], while those with Machiavellian traits may ignore affective suffering as it heightens [37].

Nonetheless, there was no evidence of higher rates of smoking, alcohol, drug use, or gambling, indicating that combat sports might not affect general risk-taking behavior. This is in line with previous findings, which found no relevant differences in substance use when comparing combat sport practitioners with the rest of the population [25].

In line with previous findings [38], the antisocial behavior scores of combat sports practitioners were significantly higher (especially in physical aggression). While combat sports participation may be associated with socially sanctioned outlets for aggression [39], their competitive and violent elements may be associated with antisocial tendencies, especially among predisposed individuals [40].

Interestingly, no significant differences were noted in relational aggression or rule-breaking behaviors, suggesting that the influence of combat sports may be more physical than interpersonal or social in nature. This supports previous findings that higher physical aggression scores have been observed among combat training participants, while relational aggression does not necessarily follow the same trend [41].

It should be noted that the combat sports group was a heterogeneous group, consisting of different styles and types (such as boxing, kickboxing, MMA, wrestling, judo, karate, taekwondo), which vary largely in technical requirements, level of physical contacts, philosophical base and culture of training [42]. Profiles of individuals may differ significantly between these types of activities. For example, traditional martial arts focused on moral development, discipline, and prosocial behavior (e.g., karate, judo and taekwondo) differ from full contact combat sports such as MMA or boxing with respect to the psychological consequences [42]. This study did not perform discipline-specific subanalyses, as this was not the primary aim. Nevertheless, further research needs to determine whether the demonstrated associations vary systematically by combat sport discipline, competitive level, and/or training context.

ADHD symptom scores were descriptively elevated in combat athletes compared to non-athletes at the group level. In the multivariable logistic regression analysis, symptoms of ADHD did not remain as an independent predictor of combat sports practice when the other clinical and personality variables were controlled for (p = 0.095). This suggests that ADHD symptoms, while perhaps descriptively more common in this population, do not appear to offer independent explanatory value over Dark Triad traits, especially narcissistic traits. While a few studies have indicated short-term advantages of regimented exercise for attention and impulse control in children with ADHD [43, 44], such effects seem to be context-dependent and may not generalize to alterations in neurodevelopmental traits in adult populations [45]. Given the cross-sectional design, longitudinal studies are needed to clarify whether ADHD symptoms represent a pre-existing vulnerability, a consequence of participation, or an incidental association in this group.

In line with literature suggesting that combat sports attract individuals with narcissistic tendencies [4], our findings showed significantly higher narcissism scores, particularly in authority, exhibitionism, exploitation, and superiority subscales [25, 26].

Higher levels of narcissistic traits and aggression were observed among combat sports participants in this sample. However, the cross-sectional design does not allow conclusions about whether combat sports contribute to these traits or whether individuals with these traits are more likely to engage in combat sports. Both self-selection and socialization mechanisms remain plausible but cannot be distinguished in the present study. Ethical guidance is essential to mitigate psychological risks. Future longitudinal, multidisciplinary research is needed. Several limitations should be considered when interpreting the findings. First, the cross-sectional design precludes any causal or directional inferences. The observed associations may reflect self-selection, socialization effects, or both; these mechanisms cannot be disentangled with the present data. Second, the sample was recruited through convenience sampling using online platforms, which may introduce selection bias and limit generalizability. The lack of a formal response rate calculation further limits the representativeness of the sample. Third, although specific combat sport disciplines were recorded for descriptive purposes, the study was not designed to compare across disciplines, and some disciplines contained relatively small numbers, making meaningful subgroup analyses unfeasible. Therefore, subgroup analyses by discipline, competitive level, or training intensity were not conducted, and the distribution of disciplines is not presented. Combat sports should not be treated as a psychologically homogeneous category. Fourth, psychiatric history variables (diagnoses, medication use, self-harm, suicide attempts) were assessed through self-report and limited to lifetime presence/absence. Moreover, specific diagnostic subtypes (e.g., depressive disorders, anxiety disorders) were not collected; only the presence of any psychiatric diagnosis was assessed. Without detailed information on timing, severity, frequency, or clinical characteristics, the clinical interpretation of psychiatric vulnerability remains limited. Fifth, the use of self-report measures for personality traits and ADHD symptoms may be subject to response biases such as social desirability. Sixth, the study was conducted in Turkey, and findings may not generalize to other cultural or geographic contexts. Seventh, although we attempted to recruit a demographically comparable control group, significant differences in age, marital status, and employment status remained between groups; these were adjusted for in multivariable analyses but may still represent residual confounding. Finally, the SEM analysis was exploratory and hypothesis-informed rather than confirmatory; the mediated paths should be interpreted as statistical indirect associations observed in this cross-sectional sample, not as causal mechanisms.

The current results have important implications for sport psychology, coaching, and mental health provision for combat sport athletes. Firstly, the high proportions of self-harm (19.3%) and suspected suicide attempts (10.0%) in the combat sports cohort may have implications for mental health screening protocols that may require further adaptation to incorporate more detailed questions about self-injurious behaviours and suicidal ideation, whether or not athletes exhibit obvious psychiatric symptomatology. Secondly, the link between Dark Triad traits and greater likelihood of legal trouble due to impulsivity (15.3% vs. 3.3% of controls) suggests that proactive behavioral contracts and anger management protocols may be necessary in combat sports leagues. Thirdly, since narcissistic traits were the strongest independent predictor of combat sports participation (OR = 1.21, p < 0.001), interventions for maladaptive narcissism, such as cognitive-behavioral interventions that aim to reduce sense of entitlement and increase empathy, might hold special promise. Lastly, in the absence of longitudinal findings, we advocate for a precautionary stance: universal annual psychological screening of combat athletes should be implemented, with minimal barriers to referral to clinical services in the event that self-harm, suicidal behavior or severe impulsivity are identified.

Conclusions

This is the first investigation to show that those who compete in combat sports are characterised by greater levels of the Dark Triad traits, particularly narcissistic traits, as well as descriptively higher ADHD symptomatology and greater psychiatric vulnerability than non-athlete controls. However, ADHD symptoms did not show independent predictive value in multivariable models, and the cross-sectional nature of the study precludes causal inference. This highlights the need for routine mental health screening in the combat sport environment, particularly for self-harm, suicidal behaviour and impulsivity-related legal concerns. Considering the detected correlations, a holistic psychological intervention could be integrated in athlete-care programs. Prospective and multidisciplinary studies are required to determine the temporal and directional aspects of these relationships, to investigate sport-specific differences and to assess the efficacy of sport-specific interventions in the enhancement of mental health in combat sport athletes.

Author contributions

I.A.İ. conceived and designed the study, developed the study protocol, supervised the research process, performed the statistical analyses, interpreted the data, and drafted the manuscript. Ş.A. contributed to participant recruitment, data collection, data interpretation, and critically revised the manuscript for important intellectual content. Both authors reviewed and approved the final version of the manuscript and agree to be accountable for all aspects of the work.

Funding

No sponsors were involved in this study.

Data availability

Data available on request from the authors.

Declarations

Ethics approval and consent to participate

This study was approved by the Academic Board of the Department of Mental Health and Diseases, Faculty of Medicine, Mersin University (Decision No: 2024/18, dated 13/05/2024), and by the Clinical Research Ethics Committee of Mersin University Rectorate (Decision No: 2024/538, dated 05/06/2024). All procedures were conducted in accordance with the ethical principles outlined in the declaration of Helsinki and institutional guidelines.

In the course of the study, strict adherence to ethical principles regarding data confidentiality and participant privacy was ensured. All data collection procedures were anonymized, and no personally identifiable information such as names, identification numbers, or phone numbers was collected. Each participant was assigned a random unique code to maintain anonymity. Participants were fully informed about the aims, procedures, and scope of the research via detailed information forms, and informed consent was obtained electronically. Data obtained from participants were used strictly for scientific purposes and were not shared with third parties at any stage of the study.

All participants signed the Free and Informed Consent Form before the start of the study.

Consent for publication

Not applicable. This manuscript does not contain any individual person’s data in any form (including individual details, images, or videos).

Competing interests

The authors declare no competing interests.