Mental toughness is a collection of attributes that allow a person to persevere through difficult circumstances (such as difficult training or difficult competitive situations in games) and emerge without losing confidence. In recent decades, the term has been commonly used by coaches, sport psychologists, sport commentators, and business leaders.
Mental toughness is a controversial term, in that many people use the term liberally to refer to any set of positive attributes that helps a person to cope with difficult situations. Coaches and sport commentators freely use the term mental toughness to describe the mental state of athletes who persevere through difficult sport circumstances to succeed. For example, it is often simply applied as a default explanation for any victory, which is highly problematic as an attribution. Only within the past ten years has scientific research attempted a formal definition of mental toughness as a psychological construct and criticisms about the lack of specificity of this umbrella term abound. For example, Moran (2012)  states that considerable caution is required in attempting to draw conclusions about the nature, characteristics, determinants and development of mental toughness in sport because of the theoretical nature of the definitions, which owe more to anecdotal plausibility than to empirical research.
Dr. Jim Loehr of the Human Performance Institute, in his book The New Toughness Training for Sports, defined mental toughness as "the ability to consistently perform towards the upper range of your talent and skill regardless of competitive circumstances."
Psychologists and sport psychologists have attempted to form a definition and a stronger conceptualization of mental toughness as a psychological construct. In particular, three research teams have produced both a definition and a construct definition for mental toughness.
Jones, Hanton, and Connaughton
Graham Jones, Sheldon Hanton, and Declan Connaughton of the United States used personal construct psychology in interviews with elite athletes, as well as elite-level coaches and sport psychologists, to arrive at the following definition of mental toughness:
- Mental toughness is "Having the natural or developed psychological edge that enables you to: generally, cope better than your opponents with the many demands (competition, training, lifestyle) that sport places on a performer; specifically, be more consistent and better than your opponents in remaining determined, focused, confident, and in control under pressure." (Jones, Hanton, & Connaughton, 2002, p. 209).
These same researchers published a second paper in 2007, which provided four dimensions (categories) for mental toughness attributes. One general dimension was outlined: a performer's attitude or mindset (specifically, the performer's focus and self-belief). Three time-specific dimensions were outlined: training, competition, and post-competition. These time-specific dimensions contain attributes of mental toughness (such as handling pressure, handling failure and pushing yourself to your physical limit in training) that pertain to their use at these times.
Gucciardi, Gordon, and Dimmock
Daniel Gucciardi, Sandy Gordon, and James Dimmock of Australia have proposed a different definition and framework of mental toughness, based primarily on their work with Australian footballers. Using personal construct psychology, these authors proposed the following definition of mental toughness:
Mental toughness in Australian Football is a collection of values, attitudes, behaviors, and emotions that enable you to persevere and overcome any obstacle, adversity, or pressure experienced, but also to maintain concentration and motivation when things are going well to consistently achieve your goals.— Gucciardi, Gordon, & Dimmock, 2008, p. 278, 
Although this definition was produced through work with Australian footballers, it has been generalized to other sports, including cricket  and soccer. This definition conceives of mental toughness as having both reactive and proactive qualities, meaning that mentally tough players can use mental toughness attributes to help endure and perform well during adverse situations, but can also employ other attributes of mental toughness when the game is going well, to keep them playing at their best.
Clough and Earle
Peter Clough and Keith Earle proposed a model of mental toughness, conceptualising it more like a personality trait. Their model has four components: confidence; challenge; control and commitment. In initially conceptualising mental toughness and developing the MTQ48, the approach taken by Clough et al. (2002) was to combine existing psychological theory and applied sport psychology in an attempt to bridge the gap between research and practice. Clough et al. saw clear comparisons between their emerging mental toughness data and the concept of hardiness, a key individual difference and resistance resource that helps buffer stress and has become an accepted concept in health psychology within the study of the stress-illness relationship Clough et al. are clear that mental toughness is a generic concept and should not be limited to the sports domain. They feel that sports specific measures are unlikely to move the field forward in any meaningful way. The development work relating to their model is fully described and discussed in their book on mental toughness.
Some psychologists have argued that a separate, sport-specific definitions of mental toughness should be developed. They have highlighted that the attributes of a mentally tough athlete in one sport may differ greatly from the attributes of a mentally tough athlete in a different sport. Differences have been hypothesized between male and female athletes, as well as between "team sport" and "individual sport" athletes, but to date, little empirical evidence has shown what these differences are.
Sport-specific studies of mental toughness have been conducted in cricket, soccer, gymnastics, and Australian football.     These studies have not employed a common framework, although many have used the definition of mental toughness provided by either the Jones et al. study, or the Gucciardi et al. study.
Many sports focussed studies have employed the Clough model of mental toughness. They have, using samples of athletes, shown a link between toughness, coping, emotional reactivity, psychological skills and performance.
One of the few published studies that takes mental toughness out of the sporting domain is based on the 4 'C's model. In this study it was shown that senior managers are tougher than their junior colleagues. Clough and his team are working in a number of areas outside of sport – education, health, social as well as occupational to explore the relevance of mental toughness in these areas.
There is an active debate about whether mental toughness is primarily a developed characteristic, or has a genetic basis. Two studies suggest that foundational processes occur during development that allow a person to build mental toughness throughout life. For instance, a study of American soccer players, parents, and coaches found that parents provide a "generalized form" of mental toughness upon which coaches can build a sport-specific form of mental toughness. A similar study suggested that mental toughness development proceeds first through the development of a tough attitude (strong focus and strong self-belief); upon a tough attitude, an athlete learns how to develop mental toughness attributes needed for training, then for competition. Another study examined the developmental experiences of ten super-elite athletes and found that coaches and significant adults played an important role in mental toughness development through all stages of talent development.
Conversely, the work of Horsburgh et al. (2009) demonstrates that genetic and non-shared environmental factors contribute to the development of mental toughness (as measured by the MTQ48), and that mental toughness behaves "in the same manner as virtually every personality trait that has ever been investigated in behavioural genetic study". In establishing significant relationships with the big five personality factors of Costa and McCrae (1992), these researchers have also provided evidence to support Clough et al.’s conceptualisation of mental toughness. Whilst clearly embracing the importance of genetics, Clough clearly acknowledges that mental toughness can be developed.
Mental toughness has been equated with better understood constructs from psychology such as resilience and hardiness. The term resilience is often incorrectly used interchangeably with mental toughness. However, psychologists define resilience as a positive adaptive process of coping with stress and adversity, as opposed to a collection of psychological attributes or personality traits. Hardiness has been suggested as a similar construct to mental toughness. Hardiness has typically been constructed as a personality trait, which is generally seen as stable throughout the lifetime. This differs from the conceptions of mental toughness offered by both Jones et al. and Gucciardi et al. These authors both conceive of mental toughness as unstable, arising in development, fluctuating over time, and varying for an individual performer between different sport and life scenarios. This definitional dilemma plagues the use of the term mental toughness and if mental toughness exists as a valid construct it may on occasion be maladaptive. Evidence to support this contention is derived from a study of overtraining behaviors and mental toughness by Tibbert (2013).  She reported that "the MT attributes of mental self-concept and task familiarity displayed moderate curvilinear correlations with sport-specific recovery scales of the RESTQ-Sport. The curvilinear correlations reflect decreasing recovery at the highest levels of MT. The results suggest that some attributes of MT may relate to increased ability to recover whereas other attributes are associated with lower recovery (p.2-3). Arguably mental toughness is more closely linked with goal fixedness rather than adaptability and a flexible mindset, attributes which are central to resilience.
Two instruments have been developed and validated since 2009. Gucciardi and colleagues validated the American Football Mental Toughness Inventory (AFMTI), while Sheard and Golby validated the Sports Mental Toughness Questionnaire (SMTQ). The MTQ48 pre dates these by some seven years. The factor structure of the MTQ48 has been supported by an independent research grouping led by Horsburgh (2009). Dr Lee Crust, University of Lincoln, compared the SMTQ with the MTQ 48 and concluded "Both instruments appear to tap the core components of MT but the MTQ48 seemingly provides a more comprehensive measure".
The MTQ48 questionnaire has demonstrable criterion related, construct and content validity. Reliability has been assessed by numerous independent researchers and it has clearly demonstrable internal consistency and test-retest reliability. All component scales exceed 0.70 and the overall measure has a reliability in excess of 0.90. Independent research CFA paper published in December (2012) can be accessed through AQR; MD Doug Strycharczyk was involved in the development of the MTQ48. www.aqr.co.uk Nevertheless both the construct validity and the psychometric properties of this test have been questioned by Andersen (2011).
Several instruments have purported to measure mental toughness, but research has called their validity into question. For example, the Performance Profile Inventory (PPI) developed by Jim Loehr used seven subscales to compute a mental toughness score. The Mental Toughness Inventory (MTI) developed by Middleton and colleagues measures mental toughness using twelve subscales and appears to show strong theoretical evidence for its formation. However, construct validation has only been performed with a narrow sample of athletes, leaving its psychometric properties up for debate.
- Psychological resilience
- Stress management
- Emotional resilience
- Mental resilience
- Moran, A. P. (2012). Sport and Exercise Psychology: A Critical Introduction (2nd ed.). Routledge.
- Jones, G., Hanton, S., & Connaughton, D. (2002). What Is This Thing Called Mental Toughness? An Investigation of Elite Sport Performers. Journal of Applied Sport Psychology, 14(3), 205-218. doi:10.1080/10413200290103509
- Jones, G., Hanton, S., & Connaughton, D. (2007). A framework of mental toughness in the world's best performers. Sport Psychologist, 21(2), 243-264. Retrieved from http://www.cabdirect.org/abstracts/20073152280.html
- Gucciardi, D., Gordon, S., & Dimmock, J. (2008). Towards an Understanding of Mental Toughness in American Football. Journal of Applied Sport Psychology, 20(3), 261-281. doi:10.1080/10413200801998556
- Gucciardi, D. F., & Gordon, S. (2009). Development and preliminary validation of the Cricket Mental Toughness Inventory (CMTI). Journal of sports sciences, 27(12), 1293-310. doi:10.1080/02640410903242306
- Gucciardi, D. F. (2011). The relationship between developmental experiences and mental toughness in adolescent cricketers. Journal of sport & exercise psychology, 33(3), 370-93. Retrieved from http://www.ncbi.nlm.nih.gov/pubmed/21659669
- Coulter, T. J., Mallett, C. J., & Gucciardi, D. F. (2010). Understanding mental toughness in Australian soccer: perceptions of players, parents, and coaches. Journal of Sports Sciences, 28(7), 699-716. doi:10.1080/02640411003734085
- Clough, P.J. & Strycharczyk, D (2012) Applied mental toughness: A tool kit for the 21st Century. Kogan Page ISBN 978-0-7494-6377-9
- Crust, L. (2007). Mental toughness in sport: A review. International Journal of Sport and Exercise Psychology, 5(3), 270-290. Retrieved from http://www.informaworld.com/index/934187662.pdf
- Crust, L. (2008). A review and conceptual re-examination of mental toughness: Implications for future researchers. Personality and Individual Differences, 45(7), 576-583. Elsevier Ltd. doi:10.1016/j.paid.2008.07.005
- Bull, S., Shambrook, C., James, W., & Brooks, J. (2005). Towards an Understanding of Mental Toughness in Elite English Cricketers. Journal of Applied Sport Psychology, 17(3), 209-227. doi:10.1080/10413200591010085
- Thelwell, R., Weston, N., & Greenlees, I. (2005). Defining and Understanding Mental Toughness within Soccer. Journal of Applied Sport Psychology, 17(4), 326-332. doi:10.1080/10413200500313636
- Thelwell, R. C., Such, B. A., Weston, N. J. V., Such, J. D., & Greenlees, I. A. (2010). Developing mental toughness: Perceptions of elite female gymnasts. International Journal of Sport and Exercise Psychology, 8(2), 170-188. Retrieved from http://www.informaworld.com/index/934200511.pdf
- Gucciardi, D. F., Gordon, S., Dimmock, J., & Mallett, C. J. (2009). Understanding the coach's role in the development of mental toughness: perspectives of elite Australian football coaches. Journal of sports sciences, 27(13), 1483-96. doi:10.1080/02640410903150475
- Gucciardi, D., Gordon, S., & Dimmock, J. (2009). Development and preliminary validation of a mental toughness inventory for Australian football. Psychology of Sport and Exercise, 10(1), 201-209. doi:10.1016/j.psychsport.2008.07.011
- Gucciardi, D. F. (2010). Mental toughness profiles and their relations with achievement goals and sport motivation in adolescent Australian footballers. Journal of sports sciences, 28(6), 615-25. doi:10.1080/02640410903582792
- Gucciardi, D. F., Gordon, S., & Dimmock, J. a. (2009). Evaluation of a Mental Toughness Training Program for Youth-Aged Australian Footballers: II. A Qualitative Analysis. Journal of Applied Sport Psychology, 21(3), 324-339. doi:10.1080/10413200903026074
- Crust, L. (2009). The relationship between mental toughness and affect intensity. Personality and Individual Differences, 47, 959-963.
- Crust, L. & Azadi, K. (2010). Mental toughness and athletes’ use of psychological strategies. European Journal of Sport Science, 10, 43-51.
- Nicholls, A., & Polman, R., Levy, A., & Backhouse, S. (2008). Mental toughness, optimism, and coping among athletes. Personality and Individual Differences, 44, 1182-1192.
- Marchant, D., Polman, R., Clough, P.J., Jackson, J.G., Levy, A., & Nicholls, A.R. (2009). Mental toughness: Managerial and age differences. Journal of Managerial Psychology, 24(5), 428-437
- Connaughton, D., Hanton, S., & Jones, G. (2010). The development and maintenance of mental toughness in the World's best performers. The Sport Psychologist, 24, 168–193. Retrieved from http://www.cabdirect.org/abstracts/20103259744.html
- Connaughton, D., Wadey, R., Hanton, S., & Jones, G. (2008). The development and maintenance of mental toughness: perceptions of elite performers. Journal of sports sciences, 26(1), 83–95. doi:10.1080/02640410701310958
- p. 104
- Horsburgh, V., Schermer, J., Veselka, L., & Vernon, P. (2009). A behavioral genetic study of mental toughness and personality. Personality and Individual Differences, 46, 100-105.
- Crust, L and Clough, P.J. (2011) Developing Mental Toughness: From Research to Practice. Journal of Sport Psychology in Action, 2, 21–32
- Tibbert, S. J. (2013). MENTAL TOUGHNESS AND OVERTRAINING BEHAVIOURS Unpublished doctoral dissertation, Victoria University.
- Sheard, M., Golby, J., & van Wersch, A. (2009). Progress Toward Construct Validation of the Sports Mental Toughness Questionnaire (SMTQ). European Journal of Psychological Assessment, 25(3), 186-193. doi:10.1027/1015-5718.104.22.168
- Crust, L., & Swann, C. (2011). Comparing two measures of mental toughness. Personality and Individual Differences, 50, 217-221.
- Andersen, M. B. (2011). Who's mental? Who's tough and who's both? Mutton constructs dressed up as lamb. In: Mental toughness in sport : developments in research and theory. Gucciardi, Daniel F and Gordan, Sandy, eds. Routledge Research in Sport and Exercise Science . Routledge, Abington, Oxon, U.K. ; New York, pp. 69-88.