A multidisciplinary approach to examine mental toughness
Abstract
This thesis investigates the relationship of both trait and state explanations of Mental
Toughness (MT) upon a range of behavioural and psychophysiological outcome variables
that should relate to the construct of MT (e.g., performance, heart rate, muscle activity,
kinematic movement, and cortisol).
Chapter 1 presents a holistic overview of the strengths and limitations of research in
MT and offers some novel approaches that could advance knowledge in this area. The
introduction briefly explains different concepts that relate to the construct of MT. The
strengths and limitations of trait (personality) and state (self-report) perspectives of MT are
reviewed. Finally, future outcome variables that should be theoretically related to MT that
have yet to be fully explored are discussed. This discussion sets out in detail, the purpose of
the thesis.
Chapter 2 aimed to advance previous research findings where personality traits (i.e.,
low reward and high punishment sensitivities) have been shown to predict Mentally Tough
behaviour (MTb) and performance outcomes under pressure (e.g., Beattie, Alqallaf, & Hardy,
2017; Hardy, Bell, & Beattie, 2014). As suggested in the research overview from Chapter 1,
these individuals may demonstrate unique psychophysiological response to stress that allow
them to tolerate higher levels of pressure than their less mentally tough counterparts.
Therefore, we hypothesized that individuals high in punishment and low in reward
sensitivities (and those high in self-report MT) would show little or no increase in heart rate,
and show stable muscle activity and movement kinematics from low-stress to high-stress
conditions, compared to less mentally tough individuals. The stress condition involved
participants making a single putt where they could double or lose all the money they had
earned up to that point. Results indicated that, when reward sensitivity was low and
punishment sensitivity increased, heart rate reactivity was blunted and movement kinematics
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(club-head angle) were more consistent when transitioning from a low to high stress
environment. However, no significant relationships were found between self-report levels of
MT, psychophysiological and movement kinematic measures.
Chapter 3 addressed some of the limitations from Chapter 2. Specifically, the stress
manipulation was modified to provide participants with early warning of the stressor, and,
therefore, more time to prepare. The stress manipulation was also intensified by removing
money from participants for missed putts, and adding peer pressure by having participants
complete the experiment in pairs. We also extended the psychophysiological approach from
Chapter 2 by examining cortisol. Results regarding personality and heart rate differed slightly
from Chapter 2. Importantly, with early warning of the stressor, personality no longer
predicted heart rate reactivity, but it did predict preparatory heart rate deceleration, an index
of motor preparation. Preparatory heart rate deceleration was disrupted on transition from
low-stress to high-stress conditions, but when reward sensitivity was low, increasing
punishment sensitivity was associated with more consistent deceleration across both lowstress and high-stress conditions. Moreover, when reward sensitivity was low, increasing
punishment sensitivity was associated with less angular error (better performance). Finally,
contrary to our hypothesis, cortisol increased from the high stress condition to the low stress
condition.
Chapter 4 draws upon studies of early versus late preparation, and prevention versus
promotion focus, to account for the subtly different results across Chapter 2 and Chapter 3. In
doing so, it discusses the theoretical and applied implications of the thesis. Limitations and
strengths of the thesis are discussed and future resea