Systematic Review: Mental Toughness and Sports Performance, May 2020

This systematic review examines the critical role of mental toughness in professional sports performance. Conducted at University College Birmingham, the review analyzed articles from January 2004 to November 2019, focusing on the psychological elements of mental toughness, its importance for athletes, and its impact on performance across different competition levels. The study reviewed 18 articles, revealing that mentally tough athletes often exhibit problem-solving focus, high motivation, self-belief, and better coping mechanisms, which positively influence performance. However, some studies suggest that excessive mental toughness may lead to overtraining and increased injury risk. The review also explores the relationship between mental toughness and variables like practice hours and mental health, concluding that there is a strong positive association between mental toughness and sports performance, although many other factors can influence this relationship.

A systematic review of the role of mental toughness for execution
successful performance in professional sport athletes
BA Hons Sport and Fitness
University College Birmingham
Validated by: The University of Birmingham
May 2020
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Aim: To examine the role of mental toughness levels for the execution of successful sports
performance. More specifically, the current study seeks to examine psychological elements
necessary for an athlete to be mentally tough, the importance of developing and maintaining
mental toughness levels regarding sports performance, differences in mental toughness levels
between the level of competition and effects of mental toughness levels on sports performance
and outcome.
Methods: Electronic databases were searched to find trials conducted from January 2004 to
November 2019. Articles were assessed independently according to the following inclusion
criteria: (1) population: professional, semi-pro or amateur athletes, (2) intervention: mental
toughness levels assessing, competition levels assessing, psychological elements necessary for
an athlete to be mentally tough assessing, and sports performance assessing, (3) outcomes:
changes in athlete’s mental toughness levels, sports performance, or sports outcome.
Results: From the 228 articles initially identified, 18 met the criteria for detailed review.
There were randomised, and nonrandomised questioners, interviews, surveys, measures or
observations study designs. Twelve studies have shown that athletes with high levels of
mental toughness are more problem solving focused, less emotional focused, highly
motivated, have high levels of self believe, cope better with failure, recover quicker after error
and in team sports communicate more in comparison with athletes with lower levels of mental
toughness, which for the result have a positive effect on their sports performance. Two studies
have shown that higher levels of mental toughness are positively associated with higher hours
of sport-specific practice with no difference between gender and age of specialisation in a
specific sport. One study has shown that athletes with high levels of mental toughness have
significantly fewer mental health issues, such as depression and burnout. Whereas, two
studies found that athlete's sports performance and affect intensity are unrelated to mental
toughness levels.
Conclusion: Results suggest that there is a strong positive association between mental
toughness and sports performance. However, there are a lot of different variables that can
determine levels of an athlete's mental toughness and be positively or negatively associated
with mental toughness levels, which have a direct impact on sports performance.
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1.0 Introduction...........................................................................................................................4
1.1 Known about topic............................................................................................................4
1.2 Aim and objectives...........................................................................................................5
2.0 Literature review...................................................................................................................5
3.0 Methods.................................................................................................................................7
3.1 Eligibility criteria..............................................................................................................7
3.2 Information sources and search........................................................................................7
3.3 Study selection and Data collection process.....................................................................8
3.4 Risk of bias assessment method........................................................................................8
3.5 Samples.............................................................................................................................9
4.0 Results...................................................................................................................................9
4.1 Database results................................................................................................................9
4.2 Data Collection Procedure..............................................................................................16
4.3 Performance....................................................................................................................18
5.0 Discussion...........................................................................................................................19
5.1 Psychological elements necessary for an athlete to be mentally tough..........................19
5.2 Importance of developing and maintaining mental toughness levels regarding sports
performance..........................................................................................................................21
5.3 Differences in mental toughness levels between the level of competition.....................25
5.4 Effects of mental toughness levels on sports performance and outcome.......................26
6.0 Summary.............................................................................................................................32
7.0 Reference List.....................................................................................................................34
8.0 Appendix.............................................................................................................................40
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1.0 Introduction
1.1 Known about the topic
The existing body of research on mental toughness suggests that mental toughness in sport is
defined as an intentional, effectual and flexible psychological factor for enhancing and
maintaining goal-oriented pursuits (Crust, 2011, Gucciardi et al., 2015 and Powell and Myers,
2017). In the same way, the existing research recognises the critical role in sports success,
outcome, goals progresses and dealing with stressful situations played by mental toughness,
which can have positive and negative effects (Gucciardi, Gordan and Dimmock, 2008, Crust,
2011, Gucciardi et al., 2015 and Powell and Myers, 2017). Therefore, research suggests that
mentally tough athletes are those athletes who have high levels of cognitive and behavioural
effort such as; determination, focus and self-believe and who can maintain those levels over
the specific amount of time (Gucciardi, Gordan and Dimmock, 2008, Sheard, 2010 and Jones
and Parker, 2017,).
However, on the other hand, it has been demonstrated that mentally tough athletes have a
higher risk of injury during practice or in a competition by pushing their bodies over the limit
which can have a direct impact on their sports performance (Andersen, 2011, Su and Reeve,
2011, Bell et al., 2013 and Gucciardi, 2017). More specifically, athletes with high levels of
mental toughness are in a greater risk of jeopardising their injury recovery process by
ignoring possible pain, not following recommended rehabilitation process, attempting to
pursue their goals and coming back to practice and the competition before injury fully heals
which for result can have poor sports performance and possible new injuries (Andersen, 2011,
Su and Reeve, 2011, Bell et al., 2013 and Gucciardi, 2017).
Although extensive researches have been carried out on mental toughness and its relation to
sports performance, one major drawback is that all studies used questionnaires, interviews or
some similar sort of self-reported measures approach (Wright, 2017). Perhaps the most
serious disadvantages of this method are facts that samples may lie due to social desirability
or that samples can give no-valid answers due to differences in understanding and
interpretation (Wright, 2017). Additionally, there is no way that researchers can tell how
truthful and thoughtful sample have had been in responding (Wright, 2017). However,
although self-report measures approach is perhaps the most serious disadvantage of existing
literature made on mental toughness and its relationship with sports performance, in the same
way, there are no other methods available to assess mental toughness levels (Gucciardi,
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Hanton and Mallett, 2012). Therefore, self-report measures approaches are the most logical
assessment tolls (Gucciardi, Hanton and Mallett, 2012).
1.2 Aim and objectives
This systematic review aims to explore the relationship between mental toughness and sports
performance in professional athletes.
The specific objective of this systematic review was:
-To explore which psychological elements are necessary for an athlete to be mentally tough.
- To explore the importance of developing and maintaining mental toughness levels regarding
sports performance.
-To explore differences in mental toughness levels between the level of competition.
-To explore the effects of mental toughness levels on sports performance and outcome.
2.0 Literature review
It is now well established from a variety of studies that mental toughness is one of the crucial
psychological factors for success in elite sport (Golby and Sherad, 2004, Bull et al., 2005,
Jones, Hanton and Connaughton, 2007, Gucciardi, Gordan and Dimmock, 2008, Nicholls et
al., 2008, Crust and Azadi, 2010, Chen and Cheesman, 2013, Gucciardi, 2017 and Meggs and
Chen, 2018).
Several studies have examined the effects of higher and lower levels of mental toughness,
their positive and negative effects on sports performance (Connaughton et al., 2008, Chen and
Cheesman, 2013, Diment, 2014, Mahoney et al., 2014 and Jones and Parker, 2019). Results
suggest that higher levels of mental toughness will separate elite athletes and successful
performance versus athletes with lower levels of mental toughness performance
(Connaughton et al., 2008, Chen and Cheesman, 2013, Diment, 2014 and Mahoney et al.,
2014) whereby the study by Jones and Parker (2019) suggests that mental toughness levels
and sports performance are unrelated.
Similarly to the studies by Connaughton et al. (2008), Chen and Cheesman (2013), Diment
(2014), Mahoney et al. (2014) and Jones and Parker (2019), the study by Slimani et al. (2015)
examined the relationship between mental toughness and power test performances and shown
that mental toughness has a direct impact on power performance.
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On the other hand, the study by Raudsepp and Vink (2018) tested the relationship between
sport-specific exercises and mental toughness and shown higher mental toughness levels
when more hours were invested in sport-specific exercises.
In contrast to the study by Raudsepp and Vink (2018), which has been explored a
physiological relationship with mental toughness, the studies by Cowden et al. (2018) and
Vaughan et al. (2018) researched psychological resources necessary for achieving peak
performance in sport and their relationship with mental toughness. Data suggests that personal
standards and self-determination are positively related to mental toughness. However, on the
other hand, concerns over mistakes and non-self-determination are negatively related to
mental toughness.
Similarly, several studies have postulated a convergence between mental toughness and
psychological performance strategies such as self-talk, emotional control, and relaxation
strategies (Golby and Sherad, 2004, Bull et al., 2005, Jones, Hanton and Connaughton, 2007,
Nicholls et al., 2008 and Crust and Azadi, 2010). The studies by Golby and Sherad (2004),
Bull et al. (2005), Jones, Hanton and Connaughton (2007), Nicholls et al. (2008) and Crust
and Azadi (2010) reported that psychological performance strategies are positively related
with mental toughness. Results suggest that athletes with high levels of mental toughness are
more consistent in remaining focused and determined. More specifically, mentally tough
athletes cope better with the demands of the sport such as training, competition, outcome, and
lifestyle, which allows them to have better sports performance.
In the same way, the study by Meggs and Chen (2018) investigated the relationship between
sport's performance failure and Mental toughness. The study had a sampling of 80 high-level
swimmers who experienced sports outcome failure in the previous four weeks. Evidence
suggests that athletes with high levels of mental toughness are more likely to explain sport's
performance failure as being a result of controllable factors.
The study by Buhrow et al. (2017) offers probably the most comprehensive empirical analysis
of the relationship between mental toughness, early age sport specialisation, and gender. Data
suggests that there is no significant difference in those who specialise early in comparison to
those who did not. Similarly, there was no significant difference in mental toughness levels
between males and females.
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On the other hand, the study by Gerber et al. (2018) examines the importance of mental
toughness in young elite athlete's careers when they are exposed to high-stress levels.
Researchers attempted to evaluate the possible interaction of mental toughness on the burnout
and depressive symptoms in young elite athletes. The results of this study indicate that
athletes with higher levels of mental toughness reported significantly fewer health issues
when they were exposed to highs stress levels, in comparison to those with lower mental
toughness levels.
In contrast, the study by Crust (2009) reported that there is no relationship between mental
toughness and the ability of athletes to control emotions under stressful situations. This is an
important finding because it shows that athletes with high levels of mental toughness do not
perform better because they are able to control emotions under stressful situations in
competition, compared to athletes with lower levels of mental toughness.
3.0 Methods
3.1 Eligibility criteria
In November 2019, studies investigating the relationship between mental toughness and
sports performance were searched. More specifically, the focus was on the relationship
between mental toughness and sports performance and outcome in amateur, semi-pro, and
professional athletes with no restriction on gender, age, or sport. A comprehensive systematic
literature search was restricted on only journals with date cut from January 2004 to November
2019, written in English.
3.2 Information sources and search
Four different search engines databases were used to find the appropriate journals: U Search
(Electronic Library of University College Birmingham) Pub Med, Sport Discus, and Google
Scholar. In order to proceed to a strategic search, the advanced search strategies have been
used. The following terms were used: 'mental toughness in sport'. U Search (Electronic
Library of University College Birmingham) found 7797 results. In order to find reliable
sources of information, research was narrowed only on academic journals. U Search found
3925 academic journals. To reduce the number of articles and to get into a more specific
search, the logical Boolean operator 'AND' and 'NOT' have been used. New terms have been
added to the search: ‘AND sports performance, ‘AND enhance,' 'AND elite sport,' 'AND
professional athletes,' 'NOT higher education,' 'NOT students'. Electronic Library of
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University College Birmingham found 228 academic journals whereby Sport Discus found
296 academic journals.
3.3 Study selection and Data collection process
Two hundred twenty-eight academic journals found by Electronic Library of University
College Birmingham search engine and 296 academic journals found by Sport Discus were
screened by title. After duplicates have had been removed, 173 academic journals were found.
Journals which in the title did not have keywords: 'mental toughness – sport’, ‘mental
toughness – enhance’, mental toughness – elite’, ‘mental toughness – athletes’, ‘mental
toughness – performance’, mental toughness – physical’ were excluded. In the same way,
journals, which in the title have: 'Coach's influence’, ‘coach's importance’, ‘coach's
development’ and ‘comparison of different measures approach’ were excluded which
altogether narrowed number of journals to 62. Additionally, academic journals with no access
to the full text, or journals which are not written in English were excluded, which narrowed
numbers of journals to 41. The rest of the journals were read fully or by abstract in order to
assess their suitability for the systematic review. Articles were considered suitable for the
study if researchers investigated: mental toughness in relation to sports performance or
outcome, participants were amateur, semi-pro or professional athletes, mental toughness and
sport-specific practice and their relationship with sports performance, positive and negative
effects of mental toughness on sports performance, burnout or depression symptoms in
relationship with sports performance and mental toughness. After the studies were screened
by reading the abstract or full text, 18 studies have had been found to be suitable for the
current study and PICO table was done. The search process is presented, trough the PRISMA
flow diagram in the result section 4.1 (Moher et al., 2009). PICO table is presented in Table 1,
result section.
3.4 Risk of bias assessment method
To identify which studies are suitable and reliable for the current study, a critical appraisal
tool (CASP) has been used (Young and Solomon, 2009, Hannes, Lockwood and Pearson,
2010, and Nadelson and Nadelson, 2014). Critical appraisal is a systematic process used to
identify the pros and cons of a research article in order to assess the reliability and usefulness
of study findings (Young and Solomon, 2009, Hannes, Lockwood and Pearson, 2010, and
Nadelson and Nadelson, 2014). To identify the most relevant high-quality studies, the 10-step
guide has been used (Young and Solomon, 2009, Hannes, Lockwood and Pearson, 2010, and
Nadelson and Nadelson, 2014). CASP is presented in Table 2, appendix section.
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3.5 Samples
The sample size in studies was ranged from 12 to 58 years old male participants and 14 to 43
years old female participants. Three studies involved only males, and 15 studies involved both
genders. Participants were amateur, semi-pro, or professional athletes involved in the sport of
volleyball, tennis, running, swimming, football, kickboxing, cricket, and rugby. All together
in studies was involved 4420 participants, 2816 males, and 1604 females.
4.0 Results
4.1 Database results
The inclusion and exclusion of studies eligible for this study are presented trough the
PRISMA flow diagram (Moher et al., 2009). More specifically, after keywords and logical
operators 'AND' and 'NOT' has been used Electronic Library of University College
Birmingham found 228 academic journals. The process of screening studies has been taken,
which narrowed eligible studies for the current systematic review on 18. The whole process is
presented in Prisma Flow diagram. PICO table is presented in Table 1.
9

PRISMA FLOW DIAGRAM
10
Full-text articles excluded,
with reasons
(n = 21, only abstracts, no
text access, different
language, not suitable for
my aim)
Records identified through
database searching
(n =228)
Scree
ning
I
nclud
ed
Eligib
ility
Iden
tifica
tion
Additional records identified
through other sources
(n =296)
Records after duplicates removed
(n =173)
Records screened
(n =173)
Records excluded
(n =132)
Full-text articles assessed
for eligibility
(n =41)
Studies included in the
qualitative synthesis
(n =18)
Studies included in
quantitative synthesis
(meta-analysis)
(n =18)

Table 1. The PICO table.
Author Date Population Intervention Comparison Outcome
Recognised
authors
Date of
publication
Samples Which main
intervention,
prognostic factor, or
exposure am I
considering?
What is the main
alternative to
compare with the
intervention?
What can I hope to
accomplish, measure,
improve, or affect?
Golby and
Sherad
2004 115 male professional rugby
league players.
International (n=70),
Superleague (n=22) and
Division one (n=23)
Age= 18-35 (Mean = 25.5 ±
3.3).
The Psychological
Performance Inventory
(Loehr, 1986) with seven
subscales scores: self-
confidence, negative
energy control, attention
control, visualisation and
imagery control,
motivation, positive
energy control and
attitude control.
The questionnaire
developed by Maddi and
Khoshaba (2001) to
assess participants:
commitment, control,
and challenge.
The study explored
the mental skills
necessary to succeed
in a certain sport.
The results suggest that
players with higher levels
of mental toughness
scored higher in
commitment, control and
challenge, on the other
hand, payers with higher
levels of mental
toughness scored lower in
negative energy control
and attention control.
Bull et al. 2005 12 male professional cricket
players.
Interviews designed
from four subscales: a)
personal view about
winning mindset and
mental toughness, b)
personal theories how
winning mindset and
The study explored
mental toughness
levels of English
cricketers’ players
and their relationship
with their sports
performance.
The results suggest that
players with higher levels
of mental toughness have
higher levels of self-
believe, motivation,
problem coping approach,
and control over
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mental toughness were
developed, c) cope with
pressure, and d) the role
of training in the
development of mental
toughness.
emotions. Which take
altogether are essential
for the execution of
successful sports
performance.
Jones, Hanton
and
Connaughton
2007 8 elite performers. 5 male and 3
females.
With sports success of 7
Olympic gold medals and 11
world championship titles
Age = 25-48.
Interviews designed
from four subscales: a)
attitude, b) training, c)
competition and d) post-
competition.
The study explored
which psychological
and physiological
factors are necessary
for elite athletes to
consider mentally
tough
The results suggest that
higher levels of mental
toughness are associated
with problem coping
approach, optimism,
control under pressure,
determination,
confidence, control over
the emotions, self-believe
and coping with success
or failure which taken all
together have a positive
relationship with sports
performance and
outcome.
Connaughton
et al.
2008 7 (male=5 and female=2) elite
international athletes (all
athletes have been achieved
success on Olympic games)
Age = 27 to 35 years old (mean
= 33±5.3).
Face to face, or
telephone interviews.
The study explored
how to develop
mental toughness and
does mental
toughness requires
maintenance.
The results suggest that
the development of
mental toughness is a
long term process which
is strongly related to
motivational climate and
various individuals.
Additionally, desire and
motivation for success are
necessary to maintain
mental toughness.
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Nicholls et al. 2008 677 athletes. 454 male and 223
females.
International= 60, national= 99,
county= 198, club or
university= 289 and beginner=
31
Age = 15 to 58 years (Mean =
22.6±7.20).
Mental toughness
questionnaire (MTQ48).
The study explored
the relationship
between mental
toughness and
coping.
The results suggest that
higher levels of mental
toughness are related to
problem coping approach
and less with avoidance
of problem coping
approach.
Crust 2009 112 athletes, male = 55, female
= 57, involved in sports of
basketball, football, hockey,
gymnastics, badminton, golf,
and triathlon.
Age = 18 to 51 years old (male
age = 30.1±11.6, female age =
28.6±8.9).
Mental toughness
questionnaire (MTQ48),
and the Affect Intensity
Measure (Larsen, 1984)
to assess levels of
emotional reactivity
The study explored
the relationship
between mental
toughness and affect
intensity.
The results suggest that
mental toughness and
affect intensity are
unrelated.
Kaisler,
Polman and
Nicholls
2009 482 athletes. 305 male and 177
females
International=15, national=60,
county=220, club=175
Age = 16 to 45
(mean=20.44±3.98).
Mental Toughness
Questionnaire 48, and
coping strategies were
assessed via coping
factors questionnaire.
The study tested the
relationship between
mental toughness and
stressful events.
The results suggest that
athletes with higher levels
of mental toughness are
more problem-solve
focused, but less emotion-
focused.
Crust and
Azadi
2010 107 athletes, 67 male (mean
age = 22.55±4.96) and 40
females (mean age =
21.08±2.81), involved in the
sport of football, tennis, rugby,
netball, and athletic in the north
of England
Mental toughness
questionnaire MTQ48
and Test of Performance
Strategies (TOPS)
The study explored
the relationship
between mental
toughness and
psychological
performance
strategies
The results suggest that
self-talk, emotional
control and relaxation
strategies are significantly
and positively related to
mental toughness.
Chen and
Cheesman
2013 136 mixed martial arts
competitors. 89 male and 47
females.
Psychological
Performance Inventory
questionnaire and the
The study explored
the relationship
between mental
The results suggest that
professional athletes have
significantly higher levels
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Mean age = 27.1±4.8 Sports Mental
Toughness Questionnaire
toughness and levels
of competition
(amateur, semi-pro
and professional)
of mental toughness
compared to amateur and
semi-pro athletes.
Dimet 2014 19 professional football
players. Under-18 female
players on the Danish national
team=5, professional male
players playing in the top
professional league in
Denmark=5, professional male
players from Danish clubs
playing in the UEFA European
Cup competition=5, and senior
international female players
playing for Denmark in World
Cup qualifying matches=4.
Five-steps observation
instrument approach
The study explored
mental toughness
behaviours during
competitive football
games.
The results suggest that
mentally tough football
players recover quickly
after error, do more
defensive and offensive
work and communicate
more. On the other hand,
mentally, weak players
recover slowly after an
error (not running back
into position, lying on the
ground). In the same way,
aggressive behaviour after
an error such as fouling
after losing the ball or
kicking the ball away has
been shown as a sign of
mental weakness.
Mahoney et
al.
2014 Adolescent cross-country
runners recruited from high
schools in Australia.136 male
and 85 females
Age = 13 to 15 years old (mean
= 14.29±1.53).
Race times and basic
psychological needs
theory variables, mental
toughness and affect
questioner
The study tested the
relationship between
basic psychological
needs theory and
mental toughness as a
mechanism for
enhancing sports
performance.
The results suggest that
basic psychological needs
theory offers a stimulus to
the mental toughness
levels, which for the
result have enhanced
sports performance.
Slimani et al. 2016 32 high levels of male
kickboxers (winners 16 and
Mental toughness
questionnaire, upper
The study explored:
A relationship
The results suggest that
athletes with higher levels
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losers 16).
Mean age = 21.2±3.1.
Bodyweight = 70.2±9.4 kg
High= 172±0.80cm
limbs muscular power
test (MBT) and lower
limbs muscular power
test (CMJ)
between mental
toughness and
muscular power
performance. B
relationship between
mental toughness
levels and winners
and losers.
of mental toughness have
significantly higher power
tests results. In the same
way, winners scored
significantly higher on
mental test questionnaire
in compare with losers.
Buhrow et al. 2017 102 college athletes (male=44,
female=58), involved in the
sport of swimming, golf,
basketball, track and field cross
country, softball, tennis,
football, soccer, and wrestling
Age = 18-23 (Mean = 20.12)
Demographic
questionnaire,
Psychological
Performance Inventory
The study tested the
relationship between
mental toughness and
age of specialisation
in sport and
differences in mental
toughness based on
the early
specialisation of
sport and gender.
The results suggest that
there is no significant
difference in the mental
toughness of athletes who
specialised in the sport
early in compare with
athletes who did not.
Additionally, there was
no significant difference
in mental toughness
scores based on gender.
Gerber et al. 2018 257 athletes. 165 male and 92
females.
Mean age = 16.82±1.44
Mental toughness
questionnaire, Shirom-
Mental Melamed
Burnout Measure
(SMBM), Patient health
questionnaire (PHQ) and
Perceived stress scale
(PSS)
The study explored
the relationship
between mental
toughness, burnout,
depression and stress.
The results suggest that
young athletes with
higher levels of mental
toughness reported
significantly lower levels
of burnout, depression
and stress.
Meggs and
Chen
2018 80 (male=44, female=36), high
levels swimmers who were
currently competing and has
been experienced sports failure
in the previous four weeks. Age
Mental Toughness
Questionnaire 48 and 16
items self-report measure
questionnaire, which
requires that participants
The study tested the
relationship between
mental toughness and
perceived failure and
its effects on sports
The results suggest that
athletes with higher levels
of mental toughness cope
well with failure, and they
are able to maintain self-
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= 17 to 26 years old (mean =
21.64±4.96).
identify the main reason
of their performance and
then rate this along with
four subscales
(controllability, stability,
globality and
universality).
performance. believe after a perceived
failure.
Radusepp and
Vink
2018 175 adolescent Estonian
volleyball players
84 males and 91 females
Age = 14 to 15 years (mean =
15.2 ± 0.82)
Mental Toughness
Inventory (Gucciardi et
al., 2015) and sport-
specific practice was
measured through
weakly diary, in which
participants reported the
hours involved in
specific practice
The study tested the
relationship between
sport-specific
practice and mental
toughness
The results suggest that
higher mental toughness
levels are related to
higher hours of sport-
specific practice.
Cowden et al. 2019 318 high levels tennis players,
male=218, female=100
Age =15 to 25 (Mean =
17.61±2.41).
Integrative modelling
approach
The study tested the
relationship between
personal standards
(PSP) and concerns
over mistakes (CMP)
and mental toughness
(MT) and self-
determined
motivation (SDM),
non-self-determined
motivation (NSDM)
The results suggest that
PSP was related
positively with MT. On
the other hand, CMP was
related negatively with
MT. MT was related
positively with SDM.
Additionally, MT was
unrelated to NSDM.
Jones and
Parker
2019 330 triathlon athletes. 183
male and 147 females
Mean age = 39.23 ± 8.93.
Mental toughness
questionnaire and
personal best triathlon
times
The study tested the
relationship between
mental toughness and
Olympic distance
personal best
The results suggest a
small, moderate size
negative relationship
between mental toughness
and personal best
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triathlon times. triathlon times.
17

4.2 Data Collection Procedure
All participants received detailed information about the process and purpose of the studies
prior to data collection. In the same way, all studies were ethnically approved prior to sample
and data collection.
The studies by Nicholls et al. (2008), Crust (2009), Kaisler, Polman and Nicholls (2009), and
Chen and Cheesman (2013) collected data by using mental toughness questionnaire
(MTQ48). The mental toughness questionnaire (MTQ48) assessed global mental toughness
and six subscales: commitment, challenge, interpersonal confidence, confidence in own
abilities, control over emotions, and life control (Clough, Sewell and Earle, 2002). Answers
were ranged on a point scale from one (strongly disagree) to five (strongly agree) (Clough,
Sewell and Earle, 2002)
Also, the study by Crust and Azadi (2010) collected data by using mental toughness
questionnaire (MTQ48) and Test of performance strategies (TOPS). Test of performance
strategies (TOPS) is 64 items questionnaire. Design to assess psychological skills and
strategies used by athletes during practice or competition. Answers were ranged on a scale
from one (never) to five (always).
Whereby the studies by Mahoney et al. (2014) and Jones and Parker (2019) collected data by
using mental toughness questionnaire (MTQ48) and sport-specific performance results. Sport
performance data was collected to measure cross-country runners race times (Mahoney et al.,
2014), and triathlon athletes' best personal times (Jones and Parker, 2019).
In the same way, the study by Slimani et al. (2016) collected data by using mental toughness
questionnaire (MTQ48) and body power tests. Body power tests were conducted on the upper
body and lower body. For upper body was used a medicine ball throw explosive power test
and for lower body countermovement jump test.
Similarly, the study by Gerber et al. (2018) collected data by using mental toughness
questionnaire (MTQ48), One Shirom-Mental Melamed Burnout Measure (SMBM), Patient
health questionnaire (PHQ) and Perceived stress scale (PSS). Shirom-Mental Melamed
Burnout Measure (SMBM) was 14 items questionnaire with three subscales: 6 questions
about physical fatigue, five questions about cognitive weariness, and three questions about
emotional exhaustion. Whereas, patient health questionnaire (PHQ) is a tool for diagnosing
18

mental health disorders and covering five subscales: depression, anxiety, somatoform,
alcohol, and eating. Furthermore, the perceived stress scale (PSS) is a stress assessment
instrument. PSS questionnaire was designed to ask questions about feelings and thoughts
during the last month.
Also, the study by Meggs and Chen (2018), collected data by using mental toughness
questionnaire (MTQ48) and one self-report attributions questionnaire. Self-report attributions
questionnaire (the CSGU) was designed to collect data about an athlete's most recent
perceived failure.
On the other hand, the studies by Bull et al. (2005), Jones, Hanton and Connaughton (2007),
Connaughton et al. (2008) collected data by using mental toughness interviews approach.
Interviews were conducted by telephone or face to face. The aim of the interviews was to
assess mental toughness levels. Interviews were recorded, typed, and lasted between 100 and
180 minutes.
In contrast, the studies by Golby and Sherad (2004), Chen and Cheesman (2013) and Buhrow
et al. (2017) collected data by using Psychological Performance Inventory questionnaire.
Psychological Performance Inventory (the PPI) assessed overall mental toughness and six
subscales: self-confidence, negative energy control, attention control, visualisation and
imagery control, motivation, positive energy, and attitude control. Answers were ranged on a
point scale from one to five.
Similarly, the study by Radusepp and Vink (2018) collected data by using Psychological
Performance Inventory questionnaire and sport-specific practice data. The sport-specific
practice was used in volleyball. Athletes recorded hours and minutes of their involvement in
sport-specific practice per day by using a weakly training diary.
The study by Dimet (2014) collected data by using five steps observation approach. Five steps
observation approach was used to observe football players during the match and practice. Step
one was to observe training. The aim was to ensure familiarity with systematic observation
protocols to minimise any chances of possible errors and incorrect scoring. Step two was to
create a systematic observation instrument with a list of specific behaviours that researchers
were aiming to explore. Step three was to determine which and how certain behaviours are
related to mental toughness. Step four was to establish how to score certain behaviours on the
mental toughness scale. To ensure the correct scoring system, researchers were following
19

protocol created by Brewer and Jones (2002), in which three coaches and two sports
psychologists have videotaped examples of the top 10 ranked mental behaviours in the certain
sport and compare those behaviours with behaviours of the samples included in the study.
Step five was to collect all data and grade certain behaviours on the mental toughness scale.
Whereby the study by Cowden et al. (2019) have had collected data by using integrative
modelling approaches. The integrative modelling approach was designed as the questionnaire
with five subscales: personal standards, concerns over mistakes, mental toughness, self-
determined motivation, and non-self-determined motivation.
4.3 Performance
Eleven studies have shown that athletes with high levels of mental toughness are more
problem solving focused, less emotional focused, highly motivated, have high levels of self
believe, cope better with failure, recover quicker after error and in team sports communicate
more in comparison with athletes with lower levels of mental toughness, which for the result
have a positive effect on their sports performance (Golby and Sherad, 2004, Bull et al., 2005,
Jones, Hanton and Connaughton, 2007, Connaughton et al., 2008, Nicholls et al., 2008,
Kaisler, Polman and Nicholls, 2009, Crust and Azadi, 2010, Dimet, 2014, Mahoney et al.,
2014, Meggs and Chen, 2018 and Cowden et al., 2019).
In the same way, two studies have shown that higher levels of mental toughness are positively
associated with higher hours of sport-specific practice with no difference between gender and
age of specialisation in a specific sport (Buhrow et al., 2017 and Radusepp and Vink, 2018).
Similarly, one study has shown that athletes with high levels of mental toughness have
significantly fewer mental health issues, such as depression and burnout (Gerber et al., 2018).
Two studies have shown that professional athletes have significantly higher levels of mental
toughness compared to semi-pro and amateur athletes (Chen and Cheesman, 2013 and
Vaughan et al., 2018).
Also, two studies found that athlete's sports performance and affect intensity are unrelated to
mental toughness levels (Crust, 2009 and Jones and Parker, 2019).
In contrast, the study by Slimani et al. (2016) found that an athlete's sports performance and
mental toughness levels are directly related.
20

These results suggest that there is a strong positive association between mental toughness and
sports performance. However, there are a lot of different variables that can determine levels of
an athlete's mental toughness and be positively or negatively associated with mental
toughness levels, which have a direct impact on sports performance.
5.0 Discussion
As mentioned in the introduction section, this systematic literature review seeks to examine
the role of mental toughness levels for the execution of successful sports performance. More
specifically, the current study seeks to examine psychological elements necessary for an
athlete to be mentally tough, the importance of developing and maintaining mental toughness
levels regarding sports performance, differences in mental toughness levels between the level
of competition and effects of mental toughness levels on sports performance and outcome.
5.1 Psychological elements necessary for an athlete to be mentally tough
The study by Bull et al. (2005) aimed to explore which psychological factors are related to
mental toughness levels of English cricketers’ players and how can it affect their sports
performance. The samples involved in the study were 12 male professional cricket players
who were selected by their coaches and researchers as mentally tough athletes based on their
performance and sports success over the years of their careers. Data was collected through
interviews designed from four subscales: a) personal view about winning mindset and mental
toughness, b) personal theories how winning mindset and mental toughness were developed,
c) cope with pressure, and d) the role of training in the development of mental toughness. The
results suggest that players with higher levels of mental toughness have higher levels of self-
believe, motivation, problem coping approach, and control over emotions. Which take
altogether are essential for the execution of successful sports performance. However, sample
size, selection bias, unknown age, and gender approach are serious weaknesses of the study
by Bull et al. (2005) (Hernan, Hernandez-Diaz and Robins, 2004 and Schaal et al., 2011). It
would be interesting to see how larger, randomly assigned sample size, including both
genders from different sports, would react on intervention. Also, data was collected via
interviews, so it is questionable reliability of answers given by the athletes as well as the fact
that answers can change over the time (Nicholls et al., 2005, Nicholls et al., 2006).
The similar aim has had the study by Jones, Hanton and Connaughton (2007) which aimed to
examine which psychological and physiological factors are necessary for elite athletes to
consider mentally tough. However, the study by Jones, Hanton and Connaughton (2007) used
21

male and female samples. Samples were elite sports performers selected using a purposive
sampling approach, ranged from 25 to 48 years old, five male and three females, with sports
success of seven Olympic gold medals and 11 world championship titles. Data was collected
through interviews designed from four subscales: a) attitude, b) training, c) competition and d)
post-competition. The results shown score 9.33 ± 1.05 out of 10, participants agreed that to be
considered mentally tough and to have and maintain successful sports performance following
aspect are necessary: a) coping better than opponents with training, competition and lifestyle,
b) determination, c) focus, d) confidence, and e) control under pressure. In the same way, as
in the study by and Bull et al. (2005), the main weakness of the study by Jones, Hanton and
Connaughton (2007) is selection bias, as is unknown in which way participants were chosen
or recruited (Hernan, Hernandez-Diaz and Robins, 2004). Also, another limitation is the fact
that data was collected via interviews approach, so it is questionable reliability of it (Hernan,
Hernandez-Diaz and Robins, 2004 and Nicholls et al., 2005). Additionally, the study used a
small sample size with only highly sports-successful samples, so it would be interesting to see
their results in comparison to the other professional athletes with less sports-success.
In the same way, the study by Nicholls et al. (2008) explored which psychological and
physiological factors are necessary for elite athletes to consider mentally tough. However, the
study used 667 samples (454 male athletes and 223 female athletes), ranged from age 15 to 58
years old (mean= 22.6±7.20). Participants were athletes competed on different levels:
international= 60, national= 99, county= 198, club or university= 289 and beginner= 31.
Athletes were randomly recruited by sending letters to the sports teams within the United
Kingdom. All participants completed inform consent prior to the study. The study used
Mental toughness questionnaire (MTQ 48, Clough et al., 2002) to collect data and assess
mental toughness levels of the samples. Similarly, as in the studies by Bull et al. (2005) and
Jones, Hanton and Connaughton (2007), results of the study by Nicholls et al. (2008) indicate
a positive relationship between high levels of mental toughness and: optimism (15.82 ± 2.03
out of 20), challenge (3.76 ± 0.43 out of 4.75), commitment (3.72 ± 0.50 out of 4.91),
emotional control (3.22 ± 052 out of 4.86), life control (3.63 ± 0.51 out of 5.00) and ability
confidence (3.57 ± 0.51 out of 5.00) which taken altogether are necessary for the execution of
successful sports performance. On the other hand, the negative relationship has been found
between high levels of mental toughness and execution of successful sports performance with
pessimism (6.58 ± 2.64 out of 16) and mental distraction (1.85 ± 0.76 out of 4.50). Although
the study has significantly greater sample size and clearer sample's recruiting approach in
22

comparison to the above-mentioned studies, there are some limitations. The main weakness of
the study by Nicholls et al. (2008) is that data was measured via self-reported questionnaires,
and answers can be changed over time (Nicholls et al., 2005, Nicholls et al., 2006 and Sherad
and Golby, 2006). However, as mentioned before, there are no currently other methods
available to assess mental toughness levels, so self-reported questionnaires are the most
logical approach (Gucciardi, Hanton and Mallett, 2012).
Taken all together the results reported from the studies by Bull et al. (2005), Jones Hanton
and Connaughton (2007) and Nicholls et al. (2008) suggests that higher levels of mental
toughness are positively associated with problem coping approach, optimism, control under
pressure, determination, self-believe and coping with success or failure which taken all
together have a positive relationship with sports performance and outcome.
Also, these results indicate that athletes with higher levels of mental toughness have greater
sports performance in comparison with athletes with lower levels of mental toughness (Bull et
al., 2005, Jones Hanton and Connaughton, 2007 and Nicholls et al., 2008).
However, the researchers did not take into account how athletes who are considering to have
high levels of mental toughness can be negatively affected by their mental toughness
(Ransone and Hughes, 2004, Andersen, 2011, Franchini, Brito and Artioli, 2012, Su and
Reeve, 2011, Bell et al., 2013, and Gucciardi, 2017). The academic literature on mental
toughness has shown that mentally tough athletes have a higher risk of injury during practise
or in a competition by pushing their bodies over the limit which can have a direct impact on
their sports performance (Andersen, 2011, Su and Reeve, 2011, Bell et al., 2013 and
Gucciardi, 2017). In the same way athletes with high levels of mental toughness are in a
greater risk of jeopardising their injury recovery process by ignoring possible pain, not
following recommended rehabilitation process, attempting to pursue their goals and coming
back to practice and the competition before injury fully heals which for result can have poor
sports performance and possible new injuries (Andersen, 2011, Su and Reeve, 2011, Bell et
al., 2013 and Gucciardi, 2017).
5.2 Importance of developing and maintaining mental toughness levels
regarding sports performance.
The study by Buhrow et al. (2017) examined the relationship between mental toughness and
early sport specialisation and gender. Samples were 102 college athletes (male = 44, female =
58), 18 to 23 years old (mean age = 20.12), involved in the sport of swimming, golf,
23

basketball, track and field cross country, softball, tennis, football, soccer, and wrestling. The
convenience sampling approach was used in order to recruit participants, and participants
were assessed by using the demographic questionnaire as well as by using the Mental,
Emotional, and Bodily Toughness Inventory. No difference in mental toughness levels was
found between early age of specialisation (prior to 14 years old) in comparison to athletes
who have not specialised early (specialisation n = 133.48 ± 16.31, no-specialisation n =
135.78 ± 19.56). In the same way, there was no significant difference in mental toughness
levels between genders (men n = 134.51 ± 19.53, women = 135.82 ± 17.77). The main
weakness of the study by Buhrow et al. (2017) is that authors overlook the fact that in the
study were involved only collegiate athletes and lack of experiencing sports-specialisation
prior to high school, so it is possible that different age groups would react differently on the
intervention (Wiersma, 2000, Malina, 2010 and Buhrow et al., 2017). Additionally, the
authors overlooked the fact that it takes time for mental toughness to develop and the fact that
mental toughness levels potentially can change over time (Wiersma, 2000, Malina, 2010 and
Buhrow et al., 2017).
In the same way, the study by Connaughton et al. (2008) explored the importance of
developing and maintaining mental toughness levels in order to have successful sports
performance. The sample consisted of seven (male = 5 and female = 2) elite international
athletes (all athletes have been achieved success on Olympic games), aged between 27 to 35
years old (age = 33 ± 5.3). Data was collected via face to face or telephone interviews. Results
suggest that athletes developed their mental toughness through three stages of their life (early,
middle, and later years). Focus in the early years was on having self-believe, desire for
success, and motivation to succeed. Middle years, athletes started to experience physical and
emotional pain, competitive anxiety, uncontrollable events, and pressure of competition.
Moreover, finally, in later years, athletes reported that focus was on the development of self-
reflection, draw positive and negative experiences from the competition, physical and mental
preparation, which altogether provided a mindset for the execution of successful sports
performance. Interestingly, results showed that mental toughness levels necessary for the
execution of successful sports performance could be on their peak for three years after
competing on the high levels, so it has been shown that maintain motivation same as to have
social support network are necessary to maintain high levels of mental toughness. However,
the study by Connaughton et al. (2008) has some significant limitations such as the use of
relatively small sample size, so it is possible that different athletes would develop mental
24

toughness levels in different manners (Cote, Baker and Abernethy, 2007 and Coulter, Mallet
and Singer, 2018). Secondly, the study by Connaughton et al. (2008) collected data via self-
report measures so it is possible that answers can be changed over the time (Nicholls et al.,
2005, Nicholls et al., 2006). Also, selection bias is a potential concern as is unclear in which
way participants were recruited for the study (Hernan, Hernandez-Diaz and Robins, 2004).
On the other hand, the study by Raudsepp and Vink (2018) tested the relationship between
sport-specific practice and developing mental toughness levels. Samples were 175 Estonian
volleyball players (male = 84, female = 91), 14 to 15 years old (15.2 ± 0.82). Mental
toughness levels were assessed through the eight-item Mental Toughness Inventory
(Gucciardi et al., 2015), and sport-specific practice was measured through weakly diary, in
which participants reported they hours involved in a specific practice. Results indicate that
mental toughness levels were positively related to sport-specific practice. In 12 months,
mental toughness scores increased from 5.13 ± 0.76 to 5.39 ± 0.78, whereas sport-specific
practise increased from 7.17 ± 1.59 to 7.64 ± 1.69. However, although the study used large
sample size one of the main weaknesses of the study by Raudsepp and Vink (2018) is the use
of relatively narrow participant sample (14-16 years old Estonian volleyball players), so it is
possible that different athletes from different age groups and different sports would develop
mental toughness levels in different manners (Cote, Baker and Abernethy, 2007 and Coulter,
Mallet and Singer, 2018).
Similarly, the study by Crust and Azadi (2010) explored how mental toughness can be
developed or enhanced by using psychological performance strategies. Samples were 107
athletes (male = 67, age 22.55 ± 4.96 and female = 40, age 21.08 ± 2.81) involved in the sport
of football, tennis, rugby, netball, and athletic in the north of England. Samples were assessed
by using the Test of Performance Strategies (Thomas et al., 1999) and Mental Toughness
Questionnaire 48 (Clough et al., 2002). Results indicate the significant positive relationship of
mental toughness with self-talk (r = 0.38, P<0.01), emotional control (r = 0.36, P<0.01) and
relaxation (r = 0.29, P<0.01), whereas there was a negative relationship reported between
mental toughness and negative thinking in competition (r = -0.47, P<0.01). However,
although the study used relatively large sample size from various of sports, one of the main
limitations of the study by Crust and Azadi (2010) is the use of The Test of Performance
Strategies inventory, which assesses only the frequency with which athletes use psychological
performance strategies, so it is unclear how effective is the relationship between mental
25

toughness and psychological performance strategies in terms of sports performance and
outcome (Nicholls et al., 2008 and Nicholls et al., 2009).
In contrast, the study by Meggs and Chen (2018) examined the relationship between mental
toughness and sports failure. Participants were 80 (male = 44, female = 36), high levels
swimmers who were currently competing and has been experienced sports failure in the
previous four weeks, aged between 17 to 26 years old (age = 21.64 ± 4.96). Data was
collected via Mental Toughness Questionnaire 48 and 16 items self-report measure
questionnaire, which requires that participants identify the main reason for their performance
and then rate this along with four subscales (controllability, stability, globality, and
universality). Females showed higher scores than males on mental toughness (male = 55.98,
female = 56.56), controllability (male = 3.45, female = 3.90), and stability (male = 3.18,
female = 3.20) attributes. Whereas males scored higher on globality (male = 3.98, female =
3.65) and universality (male = 3.49, female = 3.37) attributes. Results suggest that athletes
with greater levels of mental toughness are more likely to maintain self-believe and
motivation following the defeat. However, the fact that data was collected via self-report
measures and that answers can be changed over time is a possible limitation. (Nicholls et al.,
2005, Nicholls et al., 2006). Also, it would be interesting to see measures of the relationship
between mental toughness and sports failure at different stages of the season as it is unclear if
the answers would be changed at different stages of the season (Weiss and Frazer, 1995).
Taken together data from studies by Connaughton et al. (2008), Crust and Azadi (2010),
Buhrow et al. (2017), Meggs and Chen (2018) and Raudsepp and Vink (2018) suggest that
athletes develop their mental toughness through three stages of their life and that mental
toughness levels can be further enhanced by the use of psychological performance strategies
and via sport-specific practice, which would have a positive relationship with sports
performance. Also, athletes with greater levels of mental toughness are more likely to
maintain self-believe and motivation following the unsuccessful performance. On the other
hand, data suggests there is no difference in mental toughness levels between early age of
sport-specialisation and athletes who have not specialised early, as well as that there is no
significant difference in mental toughness levels between genders. However, although the
studies have had shown important findings, narrow sample size, use of self-report
questionnaires in order to collect data and potential selection bias, questions the reliability of
results mentioned above (Nicholls et al., 2005, Nicholls et al., 2006 and Cote, Baker and
Abernethy, 2007).
26

5.3 Differences in mental toughness levels between the level of competition
The study by Golby and Sherad (2004) was aiming to investigate whether mental toughness
levels and the ability to cope with adversity within the sport would be different between
athletes operating at different levels. The study involved 115 male professional rugby league
players, ranged from 18 to 35 years old (mean age = 25.5 ± 3.3). Subjects were players from
three different levels in professional rugby: International (n=70), Superleague (n=22) and
Division one (n=23). To assess, mental toughness levels the study by Golby and Sherad
(2004) used The Psychological Performance Inventory (Loehr, 1986) with seven subscales
scores: self-confidence, negative energy control, attention control, visualisation and imagery
control, motivation, positive energy control and attitude control. On the other hand, to
measure the ability to cope with adversity within the sport, researchers assessed participants:
commitment, control, and challenge by using a questionnaire developed by Maddi and
Khoshaba (2001). The results indicate that there was a significant difference between different
levels of competition F=5.98 (P<0.001). International players scored higher on all subscales
compared to Superleague and Division one players. Mental toughness scores: International F
= 171.17 ± 17.7, Superleague F = 166.68 ± 16.68, Division one F = 161.09 ± 19.25. Ability to
cope with adversity within the sports scores: International F= 39.50 ± 5.10, Superleague F =
31.14 ± 4.66, Division one F = 29.39 ± 3.45. However, although the study has large sample
size, selection bias is a potential concern because the study used only male participants
involved in the sport of rugby, and it is the unclear way in which samples were selected other
than competition levels so it is possible that samples from different sports and gender would
react differently on the intervention (Hernan, Hernandez-Diaz and Robins, 2004). In the same
way, this study does not fully explain why International players scored higher on mental
toughness scale in comparison to the Superleague and Division one players (Connaughton et
al., 2008).
Another similar result reported the study by Chen and Cheesman (2013). The study by Chen
and Cheesman (2013) had a sample size of 136 mixed martial arts athletes (male = 89, female
= 47) competing at different levels (age = 27.1 ± 4.8). Data were collected by using the
Psychological Performance Inventory and Mental Toughness Questionnaire 48. Results
showed a strong relationship between mental toughness levels and sports performance.
Additionally, the finding suggests that elite level athletes have superior mental toughness
levels in comparison to semi-pro and amateur athletes. However, although the study had a
large sample size is the unclear way in which samples were selected other than sport and
27

competition level. Also, the study used samples involved only in one sport, so selection bias
in potential concern (Hernan, Hernandez-Diaz and Robins, 2004). Additionally, data was
measured via self-reported questionnaires, so it is questionable reliability of results mentioned
above as well as the fact that answers can be changed over time (Nicholls et al., 2005,
Nicholls et al., 2006 and Sherad and Golby, 2006). However, as mentioned before, there are
no currently other methods available to assess mental toughness levels, so self-reported
questionnaires are the most logical approach (Gucciardi, Hanton and Mallett, 2012).
Taken together these results suggests that athletes competing on high levels have significantly
higher mental toughness levels in comparison to the athletes competing on lower levels of
sports (Golby and Sherad, 2004 and Chen and Cheesman, 2013). Also, these results suggest a
positive relationship between mental toughness levels and sports performance (Golby and
Sherad, 2004 and Chen and Cheesman, 2013). However, as mentioned before the studies do
not fully explain why high levels of mental toughness are positively associated with high
levels of competition (Connaughton et al., 2008).
5.4 Effects of mental toughness levels on sports performance and outcome
The study by Diment (2014) aimed to explore mental toughness during competition. Samples
were 19 professional football players. Five under-18 female players from Danish national
team, five male professional players, playing in the top professional league in Denmark, five
professional male players from Danish clubs playing in the UEFA European Cup competition,
and four senior international female players playing for Denmark in World Cup qualifying
matches. Data was collected through five steps observation approach (Brewer and Jones, 2002
and Diment, 2014). The study reported that mentally tough football players recover quickly
after error, do more defensive and offensive work, and communicate more. On the other hand,
mentally weak players recover slowly after an error (not running back into position, lying on
the ground). In addition, aggressive behaviour after an error such as fouling after losing the
ball or kicking the ball away is shown as a sign of mental weakness. However, the study has a
relatively small sample and narrow size, so it is possible that athletes from various sports
would present different behaviours (Hernan, Hernandez-Diaz and Robins, 2004). In the same
way, it is questionable are those behaviours sign of mentally tough athletes or sign of elite
players (Jones, Hanton and Connaughton, 2007 and Coulter, Mallet and Gucciardi, 2010). It
can be argued that previously mentioned behaviours may represent a list of actions that any
28

elite football player can do and does not need to be necessary mentally tough (Jones, Hanton
and Connaughton, 2007 and Coulter, Mallet and Gucciardi, 2010).
Similar findings reported the study by Cowden et al. (2019) which tested the relationship
between personal standards (PSP) and concerns over mistakes (CMP) and mental toughness
(MT). Samples were 318 high levels tennis players (male = 218, female = 100), aged between
15 to 25 years (17.61 ± 2.41). Data was collected by using an integrative modelling approach.
Results suggest that high levels of mental toughness are positively associated with personal
standards, and self-determined motivation, whiles high levels of mental toughness are
negatively associated with concerns over mistakes and non-self-determination. Taken all
together, the study by Cowden et al. (2019) reported that athletes with high levels of mental
toughness are: highly competitive, committed, they tend to believe that they have higher
performance standards in comparison to the other competitors, and tend to rebound quickly
after an error. However, although the study has had a large sample size, there are some major
limitations. The study used samples only from one sport (tennis- individual, non-contact
sport) so it is questionable how those findings would reflect in team sports or other individual
sports (Nicholls et al., 2005, Nicholls et al., 2006, Sherad and Golby, 2006 and Cowden et al.,
2019). Secondly, the study by Cowden et al. (2019) used a cross-sectional design, so it would
be interesting to see which results would be reported through of use experimental types of
study design (Nicholls et al., 2005, Nicholls et al., 2006, Sherad and Golby, 2006 and Cowden
et al., 2019).
Also, the study by Mahoney et al. (2014) has had shown that higher levels of mental
toughness are positively associated with sports performance. The study explored the
relationship between basic psychological needs theory and mental toughness as a mechanism
for enhancing sports performance. Sampling consisted of 221 (male = 136 and female = 85)
cross-country runners, aged between 13 to 15 years old (age = 14.29 ± 1.53) recruited from
high schools in Australia. Mental toughness levels were assessed via Mental Toughness
Questionnaire 48, and sports performance was measured by collecting race times on the end-
of-season championship. Athletes whit high levels of mental toughness had greater race times
(average = -0.98 ± 0.16 seconds) compared to athletes with lower levels of mental toughness.
The study by Mahoney et al. (2014) used relatively large; however, narrow sample size.
Therefore, one of the main limitations of the study is that the authors overlook the fact that in
the study were involved only high school athletes with lack of experiencing sports-
specialisation prior to high school so it is unclear how would different age groups, sport and
29

competition levels athletes react on trial (Wiersma, 2000, Malina, 2010 and Buhrow et al.,
2017). Also, the authors overlook the fact that it takes time for mental toughness to develop
and the fact that mental toughness levels potentially can change over time (Wiersma, 2000,
Malina, 2010 and Buhrow et al., 2017).
Another positive relationship between mental toughness levels and sports-performance
reported the study by Slimani et al. (2016). The purpose of the study by Slimani et al. (2016)
was to investigate the relationship between mental toughness levels, countermovement jump
(CMJ), and medicine ball throw (MBT) power tests of high-level kickboxers. Samples were
32 high-level male kickboxers (16 winners and 16 losers, age = 22.4 ± 3.5, high =
172±0.80cm, bodyweight = 68.6 ± 12.6kg). Data was collected through mental toughness
questionnaires (MTQ48), CMJ, and MBT power testes. Results showed greater scores on both
power testes for athletes with higher levels of mental toughness in comparison to the athletes
with lower levels of mental toughness (CMJ = 36.5 versus 33.0 and MBT = 4.6 versus 4.1, P
< 0.001). Although the study by Slimani et al. (2016) shown a strong relationship between
mental toughness and sports performance, the authors overlook the fact that selection bias is a
potential concern as the study used small, gender-favourited sampling, involved only in the
sport of kickboxing, and it is the unclear way in which samples were selected other than sport
and competition level (Hernan, Hernandez-Diaz and Robins, 2004). In the same way, the
study by Slimani et al. (2016) failed to address the fact that athletes with high levels of mental
toughness can be negatively affected by their mental toughness by pushing their bodies over
the limit, ignoring possible injury or not following recommended rehabilitation process
(Ransone and Hughes, 2004, Andersen, 2011, Bell et al., 2013, Su and Reeve, 2013 and
Gucciardi, 2017). Also, questionnaire data collection approach is another possible limitation
as it was stated before that samples may lie due to social desirability or that samples can give
no-valid answers due to differences in understanding and interpretation (Wright, 2017).
However, there are no other methods currently available to assess mental toughness levels
(Gucciardi, Hanton and Mallett, 2012). Therefore, self-report measures approaches are the
most logical assessment tolls (Gucciardi, Hanton and Mallett, 2012).
On the other hand, the study by Kaiseler, Polman and Nicholls (2009) explored the
relationship between mental toughness and coping strategies of athletes, and its effects on
sports performance. Samples were 482 United Kingdom-based athletes (male = 305, female =
177), ranged between 16 and 45 years old (age = 20.44 ± 3.98). Athletes were performers
from different levels of competition (international = 15, national = 60, county = 220, club =
30

175). Mental toughness levels were assessed via Mental Toughness Questionnaire 48, and
coping strategies via coping factors questionnaire. The study by Kaiseler, Polman and
Nicholls (2009) reported that higher levels of mental toughness are positively associated with
problem-focused coping, and surprisingly higher levels of mental toughness are negatively
associated with emotion-focused coping. Data suggest that athletes with high levels of mental
toughness rate their efforts effectively only when problem-focused coping strategies are
employed, whereas mentally tough athletes are less effective when emotion-focused coping
strategies are employed. These results lead us to believe that mentally tough athletes would
perform well in problem-focused tasks, whereby they would perform less effectively in
emotion-focused tasks. The study used a large sample size with various age groups and
competition levels athletes. However, the limitation of the study by Kaiseler, Polman and
Nicholls (2009) is the use of self-reported measures data collection approaches. Therefore, in
the same way as in the study by Slimani et al. (2016) validity of collected data is questionable
(Nicholls et al., 2005, Nicholls et al., 2006, Sherad and Golby, 2006 and Cowden et al., 2019).
Similar results to the study by Kaisler, Polman and Nicholls (2009) reported the study by
Crust (2009). The study by Crust (2009) examined the relationship between mental toughness
and emotions. The sample consisted of 112 athletes (male = 55, female = 57), involved in
sports of basketball, football, hockey, gymnastics, badminton, golf, and triathlon, aged
between 18 to 51 years old (male age = 30.1 ± 11.6, female age = 28.6±8.9). Mental
Toughness Questionnaire 48 was used to assess mental toughness levels and the Affect
Intensity Measure (Larsen, 1984) to assess levels of emotional reactivity. Results showed that
mentally tough athletes in comparison to athletes with lower levels of mental toughness do
not remain relatively unaffected by emotions due to high pressure and demands of performing
on a high level (mental toughness mean = 76 versus affect intensity mean = 16, P < .05).
Surprisingly the age and gender were also found to be unrelated to mental toughness levels (r
= -.15, P > .05) and affect intensity (r = -.11, p > .05). Taken together, the results suggest a
negative relationship between mental toughness and emotion-focused tasks. The study used a
large sample size with samples of various age groups involved in different sports. However,
similarly as in the studies by Kaisler, Polman and Nicholls (2009) and Slimani et al. (2016)
the main limitations of the study by Crust (2009) is the fact that the study employed self-
report measures to collect data, so it is possible that answers can be changed over the time
(Nicholls et al., 2005, Nicholls et al., 2006, Sherad and Golby, 2006 and Cowden et al., 2019).
31

Another interesting finding showed the study by Gerber et al. (2018) which aimed to
investigate the relationship between mental toughness, burnout, depression and stress. The
study involved 257 elite athletes (165 males and 92 females, age 16.82 ± 1.44), recruited in
North-Western Switzerland. Samples were followed through six months period; burnout was
assessed via Shirom-Melamed Burnout Measure (SMBM), depression via Patient Health
Questionnaire, stress via Perceived Stress Scale, and mental toughness via Mental Toughness
Questionnaire. Findings suggest that young athletes with higher levels of mental toughness
have fewer mental health issues, cope better with stressful events, and have better sports
performance compared to the young athletes with lower levels of mental toughness. However,
in the same way as in the studies by Crust (2009), Kaisler, Polman and Nicholls (2009) and
Slimani et al. (2016) the main weakness of the study by Gerber et al. (2018) is self-report
measure approach where answers can be no-valid due to social desirability or due to
differences in understanding and interpretation (Wright, 2017). However, as mentioned before
there are no other methods available to assess mental toughness levels (Gucciardi, Hanton and
Mallett, 2012). Therefore, self-report measures approaches are the most logical assessment
tolls (Gucciardi, Hanton and Mallett, 2012).
In contrast, the study by Jones and Parker (2019) reported a negative relationship between
mental toughness and sports performance. The study by Jones and Parker (2019) explored the
relationship between mental toughness and personal best triathlon times. Samples were
recruited by posting a link to the on-line triathlon forum. In the study were involved 330
triathlon athletes (male = 183, female = 147, age = 39.23 ± 8.93). Data was collected by
reporting personal best Olympic distance triathlon times and the Mental Toughness
Questionnaire. Results indicate a negative relationship between mental toughness and
personal best triathlon times. Additionally, results suggest that athletes with more experience
have greater personal best times and sports performance, which leads us to believe that the
number of hours invested in practice and competition, is more critical for the execution of
successful sports performance, rather than mental toughness levels. However, although the
study has had large sample size, samples were included only in one sport so it would be
interesting to see how athletes from different sports would react on the intervention (Hernan,
Hernandez-Diaz and Robins, 2004). Another limitation of the study by Jones and Parker
(2019) is recruitment process via the on-line forum, which can decrease the reliability of data
reported as there is no way that researchers can tell how truthful samples have had been in
responding (Sherad and Golby, 2006, Wright, 2017 and Cowden et al., 2019). Additionally,
32

the fact that researchers used the cross-sectional design of the study, which relies specifically
on self-reported measures is another limitation, so it would be interesting to see which results
would be reported through of use experimental types of study design (Nicholls et al., 2005,
Nicholls et al., 2006, Sherad and Golby, 2006 and Cowden et al., 2019).
Taken altogether, the results indicate a strong relationship between mental toughness levels
and an athlete's physical performance. More specifically, athletes with greater levels of mental
toughness recover quickly after an error, communicate more with their teammates on the
field, have an offensive mindset, and have greater muscular power (Dimet, 2014, Mahoney et
al., 2014 and Slimani et al., 2016). In the same way, the results indicate that personal
standards, self-determined motivation and coping with stressful events and problem-focused
tasks are associated positively with higher levels of mental toughness which is associated
positively with sports performance, whereas concerns over mistakes, non-self-determined
motivation, burnout, depressive symptoms and emotional-focused tasks are associated
negatively with mental toughness (Crust, 2009, Kaisler, Polman and Nicholls, 2009, Gerber et
al., 2018 and Cowden et al., 2019). On the other hand, data from the study by Jones and
Parker (2019) questions the importance of mental toughness for execution successful sports
performance, as they have had reported mental toughness levels and sports performance to be
unrelated.
However, narrow sample size, selection bias and use of questionnaires, interviews or some
similar sort of self-reported measures approach in order to collect data questions mentioned
results (Hernan, Hernandez-Diaz and Robins, 2004 and Wright, 2017). Perhaps the main
limitation of the above-mentioned studies is the use of self-reported measures approaches to
collect data, where samples can give no-valid answers due to social desirability or due to
differences in understanding and interpretation (Wright, 2017). However, on the other hand,
there are no other methods available to assess mental toughness levels (Gucciardi, Hanton and
Mallett, 2012). Therefore, self-report measures approaches are the most logical assessment
tolls (Gucciardi, Hanton and Mallett, 2012).
33

6.0 Summary
This systematic review was undertaken to explore the relationship between mental toughness
and sports performance in professional athletes.
Fifteen studies have identified that athletes with high levels of mental toughness are more
problem solve focused, less emotional focused, highly motivated, have high levels of self
believe, cope better with failure, recover quicker after error, tends to put more hours in sport-
specific practice, in team sports communicate more and have significantly less mental health
issues such as depression and burnout in compare to athletes with lower levels of mental
toughness, which for the result have a positive effect on their sports performance with no
significant difference between gender and year of specialisation in the sport. (Golby and
Sherad, 2004, Bull et al., 2005, Jones, Hanton and Connaughton 2007, Connaughton et al.,
2008, Nicholls et al., 2008, Kaisler, Polman and Nicholls, 2009, Crust and Azadi, 2010, Chen
and Cheesman, 2013, Dimet, 2014, Mahoney et al., 2014, Slimani et al., 2016, Buhrow et al.,
2017, Gerber et al., 2018, Meggs and Chen, 2018, Radusepp and Vink, 2018 and Cowden et
al., 2019). Whereas two studies identified that mental toughness levels and sports
performance are unrelated (Crust, 2009 and Jones and Parker, 2019). On the other hand, two
studies have had been identified that high levels of mental toughness are negatively associated
with emotion-focused tasks (Crust, 2009 and Kaisler, Polman and Nicholls, 2009) whereby
one study reported a negative relationship between mental toughness and sports performance
(Jones and Parker, 2019).
Overall, findings suggest that there is a strong, positive relationship between mental
toughness and successful sports performance. However, there are some major limitations of
reviewed studies such as selection bias, cross-sectional design of the studies, self-reported
questionnaires assessment approach and overlooked facts that athletes with high levels of
mental toughness have a higher risk of injury during practise or in a competition by pushing
their bodies over the limit and are in a greater risk of jeopardising their injury recovery
process by ignoring possible pain and not following recommended rehabilitation process
(Hernan, Hernandez-Diaz and Robins, 2004, Nicholls et al., 2005, Nicholls et al., 2006 and
Sherad and Golby, 2006, Andersen, 2011, Su and Reeve, 2011, Bell et al., 2013, and
Gucciardi, 2017 and Cowden et al., 2019).
Considerably more work will need to be done to determine the relationship between mental
toughness and sports performance. Large randomised, controlled trials could provide more
34

definitive evidence and avoid any potential bias. Further research should focus on determining
which specific mental toughness levels exists among the athletes for each sport individually,
what are differences between amateur, semi-pro and professional athletes in it, and how
would that affect an athlete's sports performance, abilities to cope with success, failure,
injuries, stress, mental health, and emotions. There is also a demand to develop a valid and
reliable tool for measuring mental toughness levels (Middleton, 2004).
35

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41

8.0 Appendix
Table 2. The critical appraisal tool (CASP).
1. Did the trial address a clearly focussed issue?
Golby
and
Sherad
Bull
et al.
Jones,
Hanton
and
Connaughton
Connaughto
n
et al.
Nicholls
et al.
Crus
t
Kaisler
Polman
and
Nicholls
Crust
and
Azadi
Chen
and
Cheesman
Dimet Mahoney
et al.
Slimani
et al.
Buhrow
et al.
Gerbe
r
et al.
Meggs
and
Chen
Radusepp
and
Vink
Cowde
n
et al.
Jones
and
Parker
Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes
2. Was the assignment of patients to treatments randomised?
Golby
and
Sherad
Bull
et al.
Jones,
Hanton
and
Connaughton
Connaughto
n
et al.
Nicholls
et al.
Crus
t
Kaisler
Polman
and
Nicholls
Crust
and
Azadi
Chen
and
Cheesman
Dimet Mahoney
et al.
Slimani
et al.
Buhrow
et al.
Gerbe
r
et al.
Meggs
and
Chen
Radusepp
and
Vink
Cowde
n
et al.
Jones
and
Parker
Can’t
tell
Can’t
tell
Can’t
tell
Yes Yes Yes Yes Yes Can’t
tell
Yes Yes Yes Yes Yes Yes Yes Yes Yes
3. Were all of the patients who entered the trial properly accounted for at its conclusion?
Golby
and
Sherad
Bull
et al.
Jones,
Hanton
and
Connaughton
Connaughto
n
et al.
Nicholls
et al.
Crus
t
Kaisler
Polman
and
Nicholls
Crust
and
Azadi
Chen
and
Cheesman
Dimet Mahoney
et al.
Slimani
et al.
Buhrow
et al.
Gerbe
r
et al.
Meggs
and
Chen
Radusepp
and
Vink
Cowde
n
et al.
Jones
and
Parker
Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes
4. Were patients, health workers and study personnel ‘blind’ to treatments?
Golby Bull Jones, Connaughto Nicholls Crus Kaisler Crust Chen Dimet Mahoney Slimani Buhrow Gerbe Meggs Radusepp Cowde Jones
42

and
Sherad
et al. Hanton
and
Connaughton
n
et al.
et al. t Polman
and
Nicholls
and
Azadi
and
Cheesman
et al. et al. et al. r
et al.
and
Chen
and
Vink
n
et al.
and
Parker
No No No No No No No No No No No No No No No No No No
5. Were the groups similar at the start of the trial?
Golby
and
Sherad
Bull
et al.
Jones,
Hanton
and
Connaughton
Connaughto
n
et al.
Nicholls
et al.
Crus
t
Kaisler
Polman
and
Nicholls
Crust
and
Azadi
Chen
and
Cheesman
Dimet Mahoney
et al.
Slimani
et al.
Buhrow
et al.
Gerbe
r
et al.
Meggs
and
Chen
Radusepp
and
Vink
Cowde
n
et al.
Jones
and
Parker
Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes
6. Aside from the experimental intervention, were the groups treated equally?
Golby
and
Sherad
Bull
et al.
Jones,
Hanton
and
Connaughton
Connaughto
n
et al.
Nicholls
et al.
Crus
t
Kaisler
Polman
and
Nicholls
Crust
and
Azadi
Chen
and
Cheesman
Dimet Mahoney
et al.
Slimani
et al.
Buhrow
et al.
Gerbe
r
et al.
Meggs
and
Chen
Radusepp
and
Vink
Cowde
n
et al.
Jones
and
Parker
Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes
7. Was the data analysis sufficiently rigorous?
Golby
and
Sherad
Bull
et al.
Jones,
Hanton
and
Connaughton
Connaughto
n
et al.
Nicholls
et al.
Crus
t
Kaisler
Polman
and
Nicholls
Crust
and
Azadi
Chen
and
Cheesman
Dimet Mahoney
et al.
Slimani
et al.
Buhrow
et al.
Gerbe
r
et al.
Meggs
and
Chen
Radusepp
and
Vink
Cowde
n
et al.
Jones
and
Parker
Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes
8. Will the results help locally?
Golby
and
Sherad
Bull
et al.
Jones,
Hanton
and
Connaughto
n
et al.
Nicholls
et al.
Crus
t
Kaisler
Polman
and
Crust
and
Azadi
Chen
and
Cheesman
Dimet Mahoney
et al.
Slimani
et al.
Buhrow
et al.
Gerbe
r
et al.
Meggs
and
Chen
Radusepp
and
Vink
Cowde
n
et al.
Jones
and
Parker
43

Connaughton Nicholls
Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes
9. Has the relationship between researcher and participants been adequately considered?
Golby
and
Sherad
Bull
et al.
Jones,
Hanton
and
Connaughton
Connaughto
n
et al.
Nicholls
et al.
Crus
t
Kaisler
Polman
and
Nicholls
Crust
and
Azadi
Chen
and
Cheesman
Dimet Mahoney
et al.
Slimani
et al.
Buhrow
et al.
Gerbe
r
et al.
Meggs
and
Chen
Radusepp
and
Vink
Cowde
n
et al.
Jones
and
Parker
Can’t
tell
Can’t
tell
Can’t
tell
Yes Yes Yes Yes Yes Can’t
tell
Yes Yes Yes Yes Yes Yes Yes Yes Yes
10. Is there a clear statement of findings?
Golby
and
Sherad
Bull
et al.
Jones,
Hanton
and
Connaughton
Connaughto
n
et al.
Nicholls
et al.
Crus
t
Kaisler
Polman
and
Nicholls
Crust
and
Azadi
Chen
and
Cheesman
Dimet Mahoney
et al.
Slimani
et al.
Buhrow
et al.
Gerbe
r
et al.
Meggs
and
Chen
Radusepp
and
Vink
Cowde
n
et al.
Jones
and
Parker
Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes
44