{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,4]],"date-time":"2026-07-04T15:11:36Z","timestamp":1783177896180,"version":"3.54.6"},"reference-count":82,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2022,6,5]],"date-time":"2022-06-05T00:00:00Z","timestamp":1654387200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"University of Tabriz, International and Academic Cooperation Directorate"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Biology"],"abstract":"<jats:p>There is consistent evidence that prenatal exposures to higher testosterone and lower estrogen concentrations during the first trimester of embryonal and fetal development are associated with a lower 2D:4D-ratio, which is to say: The index finger (2D) is shorter, compared to the ring finger (4D). Compared to non-active, athletes show lower 2D:4D ratios. However, athletes also report specific personality traits such as mental toughness, assertiveness, and competitive behavior. Here, we tested if 2D:4D-ratios were related to specific personality traits. We further investigated possible gender differences. A total of 460 active young adults (mean age: 24.81 years; 67% females) completed a series of self-rating questionnaires covering sociodemographic information and traits of the dark triad and mental toughness. Participants also provided a scan of their right palm hand to measure and calculate 2D:4D-ratios. t-tests, Pearson\u2019s correlations, and multiple regression analysis were performed to analyze data. Compared to male participants, female participants had a higher 2D:4D-ratio. Female and male participants did not differ as regards dark triad traits and mental toughness traits. Irrespective of gender, and based on correlational computations, 2D:4D-ratios were unrelated to the dark triad (DT) and mental toughness (MT) scores. Higher DT scores were modestly associated with higher MT scores among females, but not among males. Lower 2D:4D-ratios were associated with higher constancy scores and the male gender. The constancy and male gender appeared to be associated with lower 2D:4D-ratios.<\/jats:p>","DOI":"10.3390\/biology11060864","type":"journal-article","created":{"date-parts":[[2022,6,5]],"date-time":"2022-06-05T10:47:11Z","timestamp":1654426031000},"page":"864","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":10,"title":["Gender Differences and Relationship of 2D:4D-Ratio, Mental Toughness and Dark Triad Traits among Active Young Adults"],"prefix":"10.3390","volume":"11","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-7276-5289","authenticated-orcid":false,"given":"Seyed Hojjat","family":"Zamani Sani","sequence":"first","affiliation":[{"name":"Physical Education and Sport Sciences Faculty, University of Tabriz, Tabriz 5166616471, Iran"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1301-5522","authenticated-orcid":false,"given":"Dena","family":"Sadeghi-Bahmani","sequence":"additional","affiliation":[{"name":"Department of Psychology, Stanford University, Stanford, CA 94305, USA"},{"name":"Sleep Disorders Research Center, Kermanshah University of Medical Sciences, Kermanshah 6719851115, Iran"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Zahra","family":"Fathirezaie","sequence":"additional","affiliation":[{"name":"Physical Education and Sport Sciences Faculty, University of Tabriz, Tabriz 5166616471, Iran"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mohammad Taghi","family":"Aghdasi","sequence":"additional","affiliation":[{"name":"Physical Education and Sport Sciences Faculty, University of Tabriz, Tabriz 5166616471, Iran"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kosar","family":"Abbaspour","sequence":"additional","affiliation":[{"name":"Physical Education and Sport Sciences Faculty, University of Tabriz, Tabriz 5166616471, Iran"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4100-8765","authenticated-orcid":false,"given":"Georgian","family":"Badicu","sequence":"additional","affiliation":[{"name":"Department of Physical Education and Special Motricity, Faculty of Physical Education and Mountain Sports, Transilvania University of Bra\u015fov, 500068 Bra\u015fov, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2175-2765","authenticated-orcid":false,"given":"Serge","family":"Brand","sequence":"additional","affiliation":[{"name":"Sleep Disorders Research Center, Kermanshah University of Medical Sciences, Kermanshah 6719851115, Iran"},{"name":"Adult Psychiatric Clinics (UPKE), Center for Affective, Stress and Sleep Disorders (ZASS), University of Basel, 4002 Basel, Switzerland"},{"name":"Department of Sport, Exercise and Health, Division of Sport Science, University of Basel, 4052 Basel, Switzerland"},{"name":"Substance Abuse Prevention Research Center, Kermanshah University of Medical Sciences, Kermanshah 6714869914, Iran"},{"name":"School of Medicine, Tehran University of Medical Sciences (TUMS), Tehran 1417466191, Iran"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2022,6,5]]},"reference":[{"key":"ref_1","unstructured":"Acevedo, E.O., and Ekkekakis, P. (2006). Psychobiology of Physical Activity, Human Kinetics."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"327","DOI":"10.1016\/j.earlhumdev.2015.03.005","article-title":"Digit ratio (2D:4D) and physical fitness (Eurofit test battery) in school children","volume":"91","author":"Ranson","year":"2015","journal-title":"Early Hum. Dev."},{"key":"ref_3","first-page":"806","article-title":"Using 2D:4D digit ratios to determine motor skills in children","volume":"20","author":"Wang","year":"2016","journal-title":"Eur. Rev. Med. Pharmacol. Sci."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"e23448","DOI":"10.1002\/ajhb.23448","article-title":"The associations between digit ratio, aerobic fitness, physical skills, and overall physical fitness of elite youth distance runners","volume":"33","author":"Lombardo","year":"2020","journal-title":"Am. J. Hum. Biol."},{"key":"ref_5","doi-asserted-by":"crossref","unstructured":"Lombardo, M.P., Otieno, S., and Heiss, A. (2018). College-aged women in the United States that play overhand throwing sports have masculine digit ratios. PLoS ONE, 13.","DOI":"10.1371\/journal.pone.0203685"},{"key":"ref_6","doi-asserted-by":"crossref","unstructured":"Nobari, H., Alves, A.R., Clemente, F.M., and P\u00e9rez-G\u00f3mez, J. (2021). Influence of 2D:4D ratio on fitness parameters and accumulated training load in elite youth soccer players. BMC Sports Sci. Med. Rehabil., 13.","DOI":"10.1186\/s13102-021-00354-5"},{"key":"ref_7","doi-asserted-by":"crossref","unstructured":"Peeters, M.W., Van Aken, K., and Claessens, A.L. (2013). The Left Hand Second to Fourth Digit Ratio (2D:4D) Is Not Related to Any Physical Fitness Component in Adolescent Girls. PLoS ONE, 8.","DOI":"10.1371\/journal.pone.0059766"},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"51","DOI":"10.1016\/j.earlhumdev.2019.02.008","article-title":"The digit ratio (2D:4D) relationship with testosterone is moderated by physical training: Evidence of prenatal organizational influences on activational patterns of adult testosterone in physically-active women","volume":"131","author":"Crewther","year":"2019","journal-title":"Early Hum. Dev."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"e23070","DOI":"10.1002\/ajhb.23070","article-title":"Relationships between the second to fourth digit ratio (2D:4D) and game-related statistics in semi-professional female basketball players","volume":"30","author":"Dyer","year":"2017","journal-title":"Am. J. Hum. Biol."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"292","DOI":"10.3389\/fendo.2020.00292","article-title":"Digit Ratio (2D:4D) and Physical Performance in Female Olympic Athletes","volume":"11","author":"Eklund","year":"2020","journal-title":"Front. Endocrinol."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"e22937","DOI":"10.1002\/ajhb.22937","article-title":"Relationships between digit ratio (2D:4D) and basketball performance in Australian men","volume":"29","author":"Frick","year":"2016","journal-title":"Am. J. Hum. Biol."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"157","DOI":"10.1002\/ajhb.22627","article-title":"Relationships between digit ratio (2D:4D) and female competitive rowing performance","volume":"27","author":"Hull","year":"2014","journal-title":"Am. J. Hum. Biol."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"3175","DOI":"10.1519\/JSC.0b013e318212de8e","article-title":"Digit ratio (2D:4D) and performance in male surfers","volume":"25","author":"Kilduff","year":"2011","journal-title":"J. Strength Cond. Res."},{"key":"ref_14","first-page":"31","article-title":"Physical fitness and digit ratio (2D:4D) in male students from Wroc\u0142aw, Poland","volume":"41","author":"Koziel","year":"2017","journal-title":"Coll. Antropol."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"853","DOI":"10.1111\/j.1600-0838.2009.01031.x","article-title":"Digit ratio (2D:4D) predicts sporting success among female fencers independent from physical, experience, and personality factors","volume":"20","author":"Voracek","year":"2009","journal-title":"Scand. J. Med. Sci. Sports"},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"9","DOI":"10.3389\/fendo.2014.00009","article-title":"Digit Ratio (2D:4D): A Biomarker for Prenatal Sex Steroids and Adult Sex Steroids in Challenge Situations","volume":"5","author":"Manning","year":"2014","journal-title":"Front. Endocrinol."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"364","DOI":"10.1016\/j.physbeh.2007.09.011","article-title":"Measurement of the digit lengths and the anogenital distance in mice","volume":"93","author":"Manno","year":"2008","journal-title":"Physiol. Behav."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"20131532","DOI":"10.1098\/rspb.2013.1532","article-title":"Environmental levels of oestrogenic and antiandrogenic compounds feminize digit ratios in male rats and their unexposed male progeny","volume":"280","author":"Auger","year":"2013","journal-title":"Proc. R. Soc. B Biol. Sci."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"231","DOI":"10.1002\/ar.10108","article-title":"Sexual dimorphism in digit-length ratios of laboratory mice","volume":"267","author":"Brown","year":"2002","journal-title":"Anat. Rec."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"619","DOI":"10.1002\/ajhb.21054","article-title":"Meta-analysis of digit ratio 2D:4D shows greater sex difference in the right hand","volume":"22","author":"Watson","year":"2010","journal-title":"Am. J. Hum. Biol."},{"key":"ref_21","first-page":"50","article-title":"Digit ratio (2D:4D) and facial fluctuating asymmetry as predictors of the dark triad of personality","volume":"137","author":"Rantala","year":"2018","journal-title":"Pers. Individ. Differ."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"163","DOI":"10.1016\/S1090-5138(00)00029-5","article-title":"The 2nd: 4th digit ratio, sexual dimorphism, population differences, and reproductive success: Evidence for sexually antagonistic genes?","volume":"21","author":"Manning","year":"2000","journal-title":"Evol. Hum. Behav."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"3448","DOI":"10.1073\/pnas.1011891108","article-title":"Testosterone administration impairs cognitive empathy in women depending on second-to-fourth digit ratio","volume":"108","author":"Schutter","year":"2011","journal-title":"Proc. Natl. Acad. Sci. USA"},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"316","DOI":"10.1007\/s40806-017-0098-4","article-title":"Is Digit Ratio (2D:4D) Related to Masculinity and Femininity? Evidence from the BBC Internet Study","volume":"3","author":"Manning","year":"2017","journal-title":"Evol. Psychol. Sci."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"146","DOI":"10.1111\/j.1467-9450.2009.00758.x","article-title":"Investigating digit ratio (2D:4D) in a highly male-dominated occupation: The case of firefighters","volume":"51","author":"Voracek","year":"2010","journal-title":"Scand. J. Psychol."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"133","DOI":"10.1007\/s10508-007-9263-3","article-title":"On the Relation Between 2D:4D and Sex-Dimorphic Personality Traits","volume":"37","author":"Hampson","year":"2007","journal-title":"Arch. Sex. Behav."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"209","DOI":"10.1080\/10413200591010085","article-title":"Towards an Understanding of Mental Toughness in Elite English Cricketers","volume":"17","author":"Bull","year":"2005","journal-title":"J. Appl. Sport Psychol."},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"307","DOI":"10.1016\/j.jsams.2016.08.006","article-title":"Are mental toughness and mental health contradictory concepts in elite sport? A narrative review of theory and evidence","volume":"20","author":"Gucciardi","year":"2017","journal-title":"J. Sci. Med. Sport"},{"key":"ref_29","first-page":"128","article-title":"Psychometric properties of the Mental Toughness Questionnaire 48 (MTQ48) in elite, amateur and nonathletes","volume":"7","author":"Vaughan","year":"2018","journal-title":"Sport Exerc. Perform. Psychol."},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"229","DOI":"10.2147\/NDT.S97267","article-title":"Examining Dark Triad traits in relation to mental toughness and physical activity in young adults","volume":"12","author":"Brand","year":"2016","journal-title":"Neuropsychiatr. Dis. Treat."},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"1183","DOI":"10.1080\/17461391.2020.1825822","article-title":"The winner takes it all: The mediating role of competitive orientations in the Dark Triad and sport task performance relationship","volume":"21","author":"Vaughan","year":"2020","journal-title":"Eur. J. Sport Sci."},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"199","DOI":"10.1111\/spc3.12018","article-title":"The Dark Triad of Personality: A 10 Year Review","volume":"7","author":"FFurnham","year":"2013","journal-title":"Soc. Pers. Psychol. Compass"},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1016\/j.paid.2014.03.027","article-title":"Introduction to the special issue on the Dark Triad and related traits","volume":"67","author":"Veselka","year":"2014","journal-title":"Pers. Individ. Differ."},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"206","DOI":"10.1016\/j.paid.2018.05.002","article-title":"Harder, better, faster, stronger? Mental toughness, the dark triad and physical activity","volume":"131","author":"Vaughan","year":"2018","journal-title":"Personal. Individ. Differ."},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"64","DOI":"10.1016\/j.psychsport.2019.01.002","article-title":"The Dark Triad in male and female athletes and non-athletes: Group differences and psychometric properties of the Short Dark Triad (SD3)","volume":"43","author":"Vaughan","year":"2019","journal-title":"Psychol. Sport Exerc."},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"102","DOI":"10.1016\/j.paid.2018.01.004","article-title":"A gender role view of the Dark Triad traits","volume":"125","author":"Jonason","year":"2018","journal-title":"Pers. Individ. Differ."},{"key":"ref_37","unstructured":"Cockerill, I.M. (2002). Mental Toughness: The Concept and Its Measurement. Solutions in Sport Psychology, Cengage Learning EMEA."},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"192","DOI":"10.2466\/pms.100.1.192-194","article-title":"Relationship between Mental Toughness and Physical Endurance","volume":"100","author":"Crust","year":"2005","journal-title":"Percept. Mot. Ski."},{"key":"ref_39","doi-asserted-by":"crossref","first-page":"587","DOI":"10.1016\/j.paid.2012.04.036","article-title":"Identifying the cognitive basis of mental toughness: Evidence from the directed forgetting paradigm","volume":"53","author":"Dewhurst","year":"2012","journal-title":"Pers. Individ. Differ."},{"key":"ref_40","doi-asserted-by":"crossref","first-page":"1345","DOI":"10.3389\/fpsyg.2017.01345","article-title":"Mental toughness and individual differences in learning, educational and work performance, psychological well-being, and personality: A systematic review","volume":"8","author":"Lin","year":"2017","journal-title":"Front. Psychol."},{"key":"ref_41","doi-asserted-by":"crossref","unstructured":"Lang, U. (2019). Resilienz\u2013Resilience, Kohlhammer.","DOI":"10.17433\/978-3-17-036174-4"},{"key":"ref_42","doi-asserted-by":"crossref","first-page":"1559325818784501","DOI":"10.1177\/1559325818784501","article-title":"Enhancing and Extending Biological Performance and Resilience","volume":"16","author":"Leak","year":"2018","journal-title":"Dose-Response"},{"key":"ref_43","doi-asserted-by":"crossref","first-page":"425","DOI":"10.1017\/S0954579400005812","article-title":"Resilience and development: Contributions from the study of children who overcome adversity","volume":"2","author":"Masten","year":"1990","journal-title":"Dev. Psychopathol."},{"key":"ref_44","first-page":"39","article-title":"Validity and reliability of the Persian version of mental toughness questionnaire 48 (MTQ48)","volume":"10","author":"Afsanehporak","year":"2014","journal-title":"Sport Manag. Mot. Behav."},{"key":"ref_45","first-page":"194","article-title":"Progressing measurement in mental toughness: A case example of the Mental Toughness Questionnaire 48","volume":"1","author":"Gucciardi","year":"2012","journal-title":"Sport Exerc. Perform. Psychol."},{"key":"ref_46","doi-asserted-by":"crossref","first-page":"587","DOI":"10.1016\/j.paid.2012.11.020","article-title":"Factorial validity of the Mental Toughness Questionnaire-48","volume":"54","author":"Perry","year":"2013","journal-title":"Pers. Individ. Differ."},{"key":"ref_47","doi-asserted-by":"crossref","first-page":"905","DOI":"10.1177\/1359105314542816","article-title":"During early and mid-adolescence, greater mental toughness is related to increased sleep quality and quality of life","volume":"21","author":"Brand","year":"2014","journal-title":"J. Health Psychol."},{"key":"ref_48","doi-asserted-by":"crossref","first-page":"426","DOI":"10.1080\/02640414.2016.1167936","article-title":"During early to mid adolescence, moderate to vigorous physical activity is associated with restoring sleep, psychological functioning, mental toughness and male gender","volume":"35","author":"Brand","year":"2017","journal-title":"J. Sports Sci."},{"key":"ref_49","doi-asserted-by":"crossref","first-page":"808","DOI":"10.1016\/j.paid.2012.12.003","article-title":"Adolescents with high mental toughness adapt better to perceived stress: A longitudinal study with Swiss vocational students","volume":"54","author":"Gerber","year":"2013","journal-title":"Pers. Individ. Differ."},{"key":"ref_50","doi-asserted-by":"crossref","first-page":"164","DOI":"10.1002\/smi.2447","article-title":"Are adolescents with high mental toughness levels more resilient against stress?","volume":"29","author":"Gerber","year":"2013","journal-title":"Stress Health"},{"key":"ref_51","doi-asserted-by":"crossref","first-page":"2130","DOI":"10.3389\/fpsyg.2017.02130","article-title":"\u201cAlways look on the bright side of life!\u201d\u2014Higher hypomania scores are associated with higher mental toughness, increased physical activity, and lower symptoms of depression and lower sleep complaints","volume":"8","author":"Jahangard","year":"2017","journal-title":"Front. Psychol."},{"key":"ref_52","doi-asserted-by":"crossref","first-page":"170","DOI":"10.1016\/j.paid.2014.11.038","article-title":"Relationships between mental toughness and psychological wellbeing in undergraduate students","volume":"75","author":"Stamp","year":"2015","journal-title":"Pers. Individ. Differ."},{"key":"ref_53","doi-asserted-by":"crossref","unstructured":"Gucciardi, D., and Gordon, S. (2013). Who\u2019s mental, who\u2019s tough and who\u2019s both? Mutton constructs dressed up as lamb. Mental Toughness in Sport: Developments in Theory and Research, Routledge\/Taylor & Francis Group.","DOI":"10.4324\/9780203855775"},{"key":"ref_54","doi-asserted-by":"crossref","first-page":"232","DOI":"10.1037\/mil0000074","article-title":"Development and Validation of a Military Training Mental Toughness Inventory","volume":"27","author":"Arthur","year":"2015","journal-title":"Mil. Psychol."},{"key":"ref_55","unstructured":"Beck, N.M. (2012). Mental Toughness: An Analysis of Sex, Race, and Mood, University of North Texas."},{"key":"ref_56","doi-asserted-by":"crossref","first-page":"243","DOI":"10.1123\/tsp.21.2.243","article-title":"A Framework of Mental Toughness in the World\u2019s Best Performers","volume":"21","author":"Jones","year":"2007","journal-title":"Sport Psychol."},{"key":"ref_57","doi-asserted-by":"crossref","first-page":"699","DOI":"10.1080\/02640411003734085","article-title":"Understanding mental toughness in Australian soccer: Perceptions of players, parents, and coaches","volume":"28","author":"Coulter","year":"2010","journal-title":"J. Sports Sci."},{"key":"ref_58","doi-asserted-by":"crossref","first-page":"271","DOI":"10.1177\/0033294116687516","article-title":"Mental Toughness in South African Youth","volume":"120","author":"Cowden","year":"2017","journal-title":"Psychol. Rep."},{"key":"ref_59","doi-asserted-by":"crossref","first-page":"270","DOI":"10.1080\/1612197X.2007.9671836","article-title":"Mental toughness in sport: A review","volume":"5","author":"Crust","year":"2007","journal-title":"Int. J. Sport Exerc. Psychol."},{"key":"ref_60","doi-asserted-by":"crossref","first-page":"381","DOI":"10.1007\/s12662-019-00603-3","article-title":"Mental toughness in sport","volume":"49","author":"Liew","year":"2019","journal-title":"Ger. J. Exerc. Sport Res."},{"key":"ref_61","doi-asserted-by":"crossref","first-page":"125","DOI":"10.4085\/1062-6050-43.2.125","article-title":"Development of the Mental, Emotional, and Bodily Toughness Inventory in Collegiate Athletes and Nonathletes","volume":"43","author":"Mack","year":"2008","journal-title":"J. Athl. Train."},{"key":"ref_62","doi-asserted-by":"crossref","first-page":"1182","DOI":"10.1016\/j.paid.2007.11.011","article-title":"Mental toughness, optimism, pessimism, and coping among athletes","volume":"44","author":"Nicholls","year":"2008","journal-title":"Personal. Individ. Differ."},{"key":"ref_63","doi-asserted-by":"crossref","first-page":"182","DOI":"10.3389\/fpsyt.2018.00182","article-title":"Stability of mental toughness, sleep disturbances, and physical activity in patients with multiple sclerosis (MS)\u2014A longitudinal and pilot study","volume":"9","author":"Esmaeili","year":"2018","journal-title":"Front. Psychiatry"},{"key":"ref_64","doi-asserted-by":"crossref","first-page":"1571","DOI":"10.2147\/NDT.S111208","article-title":"Mental toughness, sleep disturbances, and physical activity in patients with multiple sclerosis compared to healthy adolescents and young adults","volume":"12","author":"Bahmani","year":"2016","journal-title":"Neuropsychiatr. Dis. Treat."},{"key":"ref_65","doi-asserted-by":"crossref","unstructured":"World Medical Association (2013). World Medical Association Declaration of Helsinki: Ethical principles for medical research involving human subjects. JAMA, 310, 2191\u20132194.","DOI":"10.1001\/jama.2013.281053"},{"key":"ref_66","first-page":"67","article-title":"Psychometric properties of Persian version of Dirty Dozen Scale","volume":"22","author":"Yousefi","year":"2016","journal-title":"Iran. J. Psychiatry Clin. Psychol."},{"key":"ref_67","doi-asserted-by":"crossref","first-page":"420","DOI":"10.1037\/a0019265","article-title":"The dirty dozen: A concise measure of the dark triad","volume":"22","author":"Jonason","year":"2010","journal-title":"Psychol. Assess."},{"key":"ref_68","first-page":"15","article-title":"Validity and reliability of the Persian version of Sport Mental Toughness Questionnaire (SMTQ)","volume":"20","author":"Kashani","year":"2015","journal-title":"Mot Behav."},{"key":"ref_69","doi-asserted-by":"crossref","first-page":"186","DOI":"10.1027\/1015-5759.25.3.186","article-title":"Progress Toward Construct Validation of the Sports Mental Toughness Questionnaire (SMTQ)","volume":"25","author":"Sheard","year":"2009","journal-title":"Eur. J. Psychol. Assess."},{"key":"ref_70","doi-asserted-by":"crossref","first-page":"155","DOI":"10.1037\/0033-2909.112.1.155","article-title":"A power primer","volume":"112","author":"Cohen","year":"1992","journal-title":"Psychol. Bull."},{"key":"ref_71","unstructured":"Cohen, J. (1988). Statistical Power Analysis for the Behavioral Sciences, Lawrence Erlbaum Associates. [2nd ed.]."},{"key":"ref_72","doi-asserted-by":"crossref","first-page":"597","DOI":"10.22237\/jmasm\/1257035100","article-title":"New Effect Size Rules of Thumb","volume":"8","author":"Sawilowsky","year":"2009","journal-title":"J. Mod. Appl. Stat. Methods"},{"key":"ref_73","unstructured":"Hair, J.F., Black, C.W., Babin, B.J., and Anderson, R.E. (2014). Multivariate Data Analysis, Pearson Education Limited. [7th ed.]."},{"key":"ref_74","unstructured":"Brosius, F. (2018). SPSS: Umfassendes Handbuch zu Statistik und Datenanalyse\u2014Comprehensive Textbook for Statistics and Data Analysis, Mitp Verlags GmBH & Co."},{"key":"ref_75","doi-asserted-by":"crossref","first-page":"85","DOI":"10.1016\/j.nlm.2018.04.012","article-title":"2D:4D and spatial abilities: From rats to humans","volume":"151","author":"Campbell","year":"2018","journal-title":"Neurobiol. Learn. Mem."},{"key":"ref_76","doi-asserted-by":"crossref","first-page":"584760","DOI":"10.3389\/fpsyg.2021.584760","article-title":"From Physical Activity Intention to Behavior: The Moderation Role of Mental Toughness Among College Students and Wage Earners","volume":"12","author":"Cao","year":"2021","journal-title":"Front. Psychol."},{"key":"ref_77","doi-asserted-by":"crossref","first-page":"35","DOI":"10.1016\/j.mhpa.2012.02.004","article-title":"Adolescents\u2019 exercise and physical activity are associated with mental toughness","volume":"5","author":"Gerber","year":"2012","journal-title":"Ment. Health Phys. Act."},{"key":"ref_78","doi-asserted-by":"crossref","first-page":"514","DOI":"10.1123\/jsep.2015-0074","article-title":"Applying the Theory of Planned Behavior to Physical Activity: The Moderating Role of Mental Toughness","volume":"37","author":"Hannan","year":"2015","journal-title":"J. Sport Exerc. Psychol."},{"key":"ref_79","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1037\/0022-3514.37.1.1","article-title":"Stressful life events, personality, and health: An inquiry into hardiness","volume":"37","author":"Kobasa","year":"1979","journal-title":"J. Personal. Soc. Psychol."},{"key":"ref_80","doi-asserted-by":"crossref","first-page":"168","DOI":"10.1037\/0022-3514.42.1.168","article-title":"Hardiness and health: A prospective study","volume":"42","author":"Kobasa","year":"1982","journal-title":"J. Personal. Soc. Psychol."},{"key":"ref_81","doi-asserted-by":"crossref","first-page":"193","DOI":"10.1016\/S0962-1849(01)80014-7","article-title":"Loss and human resilience","volume":"10","author":"Bonanno","year":"2001","journal-title":"Appl. Prev. Psychol."},{"key":"ref_82","doi-asserted-by":"crossref","first-page":"78","DOI":"10.1016\/j.cpr.2017.11.002","article-title":"Intervention studies to foster resilience\u2014A systematic review and proposal for a resilience framework in future intervention studies","volume":"59","author":"Chmitorz","year":"2018","journal-title":"Clin. Psychol. Rev."}],"container-title":["Biology"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2079-7737\/11\/6\/864\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T23:24:39Z","timestamp":1760138679000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2079-7737\/11\/6\/864"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2022,6,5]]},"references-count":82,"journal-issue":{"issue":"6","published-online":{"date-parts":[[2022,6]]}},"alternative-id":["biology11060864"],"URL":"https:\/\/doi.org\/10.3390\/biology11060864","relation":{},"ISSN":["2079-7737"],"issn-type":[{"value":"2079-7737","type":"electronic"}],"subject":[],"published":{"date-parts":[[2022,6,5]]}}}