Motivation and emotion/Book/2017/Exercise and negative emotions

Exercise and negative emotion:
What role can physical exercise play in regulating negative emotions?

Overview

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Figure1. Exercise contributes to a happy healthy lifestyle

The physiological benefits of living a healthy active lifestyle have become well known and widespread. The role exercise plays in regulating negative emotion has not been as widely disseminated. Researchers are beginning to explore the effect that physical exercise can have on regulating negative emotions and ways in which these effects can be controlled and manipulated in order to facilitate better health outcomes for everyday life.

Focusing on the relationship between exercise and negative emotion is an important area of study given the increasing importance of mental health in modern society. Recent figures from the Australian Bureau of Statistics show that in 2013 10.8% of adults reported high levels of psychological distress (ABS, 2013). At the end of 2015 this figure has grown to 11.7% (ABS, 2015). The Australian Bureau of Statistics has also explored the comorbidity between mental health and physical health problems and found 94.1% of the population with mental health or behavioural conditions also reported long term physical health conditions (ABS, 2015). The prevalence of mental health issues and its effect on physiology highlight the need to explore what role exercise can play in regulating negative emotion.


Test yourself !

What percentage of adults report psychological Distress in Australia according to most recent figures ?

8%
15%
11.7%

What are negative emotions?

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Figure 2. Van Goh's Old Mans Sorrow - art depicting negative emotion in humans

Emotions reflect how we behave in response to every aspect of life. Emotions influence how we interact with others in our social environment (Lopes, Salovey, Beers & Petty, 2005), our cognitive processes, decision making (Thompson, 2008), individual development (Hesse & Cicchetti, 1982), and our behaviour (Baumeister, Vohs, DeWall and Zhang, 2007). Existing literature approaches defining emotion through the use of prototypes, such as; anger, happiness, joy, and sadness etc (Fehr & Russell, 1984). This approach is helpful given the diversity of human emotions.

 
Figure 3. Plutchik wheel showing prototypical emotions

Emotion can be operationally defined as a mental experience with high intensity which causes pleasure or displeasure (Cabanac, 2002). This definition attempts to encompass the broad range of individual emotional responses that can be expressed; such as anger joy, shame, guilt, triumph or empathy. Cabanac (2002) identifies four main dimensions of emotional experience; quality, intensity, hedonicity, and duration. For example using this model anger is defined as an emotion because it has a negative quality, high intensity, is displeasurable and has a duration linked to the experience of the object or stimulus that caused the response. In comparison, a cognitive process such as thinking, does not have a negative or positive quality, has a neutral intensity, can be both displeasurable and pleasurable and does not have a distinct duration, it therefore does not fit Cabanac's (2002) definition of emotion. Negative emotion can therefore be described as an intense mental response that causes a displeasurable experience.

Does emotion interact with physiology?

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Studies show that there is a relationship between physiology and emotion. The James-Lange Theory of emotion proposes that emotion is the description we use to label our response to a physical stimulus (James, 1994; Schioldann, 2011). The theory proposes that emotion is the label given to a physiological response to an environmental stimulus rather than a direct response to the stimulus itself. For example according to the James-Lange theory (James, 1994; Schioldann, 2011) the experience of an emotional state such as fear is a response to physiological changes (eg. increased heart rate, trembling, sweating etc) and not the stimulus object triggering the physiological response (Reisenzein, Meyer & Schützwohl, 1995).

Other studies agree that physiology interacts with emotion but argue that physiology alone cannot explain emotion (Cannon, 1931). Walter B Cannon (1931) argues that emotion is too complex and multi dimensional to be singularly accounted for by physiological processing. For example the physiological response of sweaty palms could indicate a multitude of emotional responses, such as fear, nervousness, excitement or general arousal.

Modern views of emotion apply an integrative two-factor approach (Schachter & Singer, 1962). The two-factor theory of emotion proposes that physiology and cognitive experience both play a role in the formation of emotional states (Schachter & Singer, 1962). The theory proposes that emotional experience relies on contextual cues taken from the environment and past experience in order to cognitively interpret physiological stimuli and produce an emotional response (Schachter & Singer, 1962). According to the theory, without cognitive context the emotional state cannot be accurately explained.


Test yourself !

Which of these is not a component of emotion according to Cabanac (2002) ?

Sadness
Intensity
Duration

What role does physical exercise play in regulating negative emotions?

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Growing evidence indicates that physical exercise plays a significant role in improving mental health through the regulation of negative emotions (Edwards, 2006). Physical exercise can also impact mental disorders associated with negative emotion such as depression (Daley, 2008 ; Fox, 1999) and anxiety (Wipfli, Landers, Nagoshi & Ringenbach, 2011). Meta-analytical studies have shown that exercise has an effect on both mental health disorders as well as general mental wellbeing (Craft & Landers, 1998). Effective exploration of this relationship requires an In depth look at the biological, cognitive and social impacts of exercise and the regulatory influence these have on negative emotion.

Biological effects of physical exercise

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Figure 4. Serotonin molecule showing chemical structure

Physical exercise triggers a multitude of biological processes within the human body including hormone and neurotransmitter release. Some research has indicated that the release of post exercise neurotransmitters regulate negative emotions (Wipfli et al., 2011). In particular, studies have implicated both monoamines and endorphin release as negative emotion regulators (Peluso & Andrade, 2005). Endorphins released post exercise perform a similar role to SSRI medication which is employed in the pharmacological treatment of depression in clinical psychology and psychopathology (Wipfli et al., 2011). Physical exercise may also have a direct association with SSRI medication through the poste[spelling?] exercise release of serotonin 5-hydoxytryptamine (Fox, 1991).

Exercise also has long term effects on neurobiology and causes neurotrophic effects to occur through increased neurotransmitters release (Matta Mello Portugal et al., 2013). One study examined the efficacy of using exercise in clinical psychology treatments and found support for the effects of both monoamine and endorphin levels post exercise on negative mood and emotion, which are symptoms of major depressive disorder (Brosse, Sheets, Lett & Blumenthal, 2002)[Provide more detail].

Other neurotransmitters such as norepinephrine have also been implicated as having an effect on stress responses and anxiety levels post exercise (Dishman, 1997). This effect has been investigated by comparing norepinephrine levels before and after treadmill running in rats (Dunn, Reigle, Youngstede, Armstrong & Dishman, 1996). Existing studies have provided support for the effect of norepinephrine and serotonin, which are used in traditional pharmaceutical treatments (Harmer, Shelley, Cowen & Goodwin, 2004).

 
Figure 5. Norepinephrine molecule showing chemical structure

One of the more overt physiological effects of exercise is changes to physical health and weight reduction. This effect plays an integral role in mitigiating[spelling?] negative emotions that stem from poor self perceptions, social comparisons and self worth which is impacted by obesity and poor physical health (Friedman et al., 2005). It has also been suggested that physical exercise can have a direct effect on brain anatomy. Studies have already shown that physical exercise can play a moderating role in degenerative brain diseases such as dementia (Dishman et al., 2006). Studies have shown that intense physical activity increases left frontal lobe activation which has been implicated in the cognitive understanding of emotional stimuli (Hall, Ekkekakis & Petruzzello, 2007).

Cognitive effects of physical exercise

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Physical exercise also impacts the cognitive processes of individuals. Exercise can effect our self efficacy, body image and cognitive focus.

Self-efficacy and self-perception

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The way in which people perceive themselves in relation to their environment and society is an important determinant of behaviour (Ajzen, 2002). It has been suggested that physical exercise promotes changes in self efficacy which in turn provide opportunities for emotional change (Fox, 1991). A study conducted by Megakli, Vlachopoulos, Thøgersen-Ntoumani and Theodorakis (2015) showed that physical exercise has the ability to modify self perceptions and exercise efficacy. This increase in perceived behavioural control can contribute to a reduction in negative emotions and attitudes towards the self (Perugini & Bagozzi, 2001). Subsequent research has supported this relationship, and it's application in treating anxious and depressive disorders. (Knapen et al., 2005). Netz, Wu, Becker and Tenenbaum, (2005) suggest that the association between physical exercise, self efficacy and reductions in negative emotion are associated with social cognitive theory (Bandura, 1991).

Bandura's (1991) Social cognitive theory proposes that motivation and behaviour are influenced by an individuals belief in their ability or agency to perform an action within the environmental context they are placed. It is suggested that the resulting self efficacy improvements caused by physical exercise facilitate less conflict in the social cognitive processing of individuals resulting in less perceptions of negative emotions (Netz et al., 2005). Bandura (1991) also proposes that these feelings of agency and self control also contribute to overall wellbeing and life satisfaction.

Cognitive dissonance and body image

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Physical exercise can also influence emotional perceptions through moderating cognitive dissonance. Cognitive Dissonance theory proposes that humans experience psychological distress as a result of discrepancies between their ideal self and present self (Festinger, 1962). Exercise can play a role in reducing this discrepancy and creating a more congruent self perception by bringing individuals closer to their ideal self (Sonstroem & Potts, 1996; Van Camp & Hayes, 2012). Research also indicates that improved self perceptions are associated with overall life adjustment and emotional satisfaction (Sonstroem & Potts, 1996) and that these effects are maintained long term in a parallel correlation with exercise participation (Opdenacker, Delecluse & Boen, 2009). Interestingly, studies show a reciprocal relationship: increased discrepancies between ideal and actual body image are predictive of exercise behaviours (Anton, Perri & Riley, 2000). This provides further support for the idea that participating in exercise reduces dissonance and improves emotional wellbeing.

Distraction Hypothesis

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Physical exercise can also moderate negative emotions by providing an effective distraction or outlet for cognitions (Craft & Perna, 2004). The Distraction Hypothesis theory proposes that mood, affect and emotional states are influenced by activities that provide an alternative focus outside of distressing or anxious thoughts (Russell et al., 2002). This effect has been observed in physical activity exercise (Berger & Motl, 2000). Russell et al. (2002) compared the effectiveness of exercise as a distraction activity with current distraction methods recommended by clinicians, e.g. meditating, reading and social interaction. The study found exercise to be equal in its distraction effect when compared to other common methods and recommended it's used as a clinical aid for mental wellbeing (Russell et al., 2002). Research also indicates that exercise may have a similar effect of distracting from aversive emotional states to that of humour (Szabo, 2003).

What are the social effects of physical exercise?

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Sport and social interaction increase positive emotions (McIntyre, Watson & Cunningham, 1990). Sport and exercise provides an avenue for increased social interaction and studies have shown a positive correlation between exercise participation and improved emotional wellbeing, particularly within team sports (Wann, 2006). A case study testing whether an intervention combining group physical activity with a support network produced better emotional wellbeing outcomes compared to a control group exposed to social support only provides support for this concept (Armstrong & Edwards, 2003). Exercise provides opportunity to extend social environments and facilitate interaction between participants (Kawachi, 2001).

Modern society places increased emphasis on health and fitness. This has placed greater amounts of social pressure on individuals (Yun & Silk, 2011). Research indicates that exercise participation is facilitated by social support and impacts affective attitudes (Rhodes, Jones & Courneya, 2002). Exercising at least twice a week has a significant impact on self reported feelings of integration and coherence with societal expectations (Hassmén, Koivula & Uutela, 2000). The increased social pressures of modern society to be healthier, thinner, stronger and more attractive present significant challenges to emotional health (Russell, 2002; Myers & Rosen, 1999). While the social pressures can be viewed as negative contributors to psychological distress they do have the effect of reinforcing physical exercise behaviours. Research shows that body dissatisfaction contributes to negative mental health outcomes (Ganem, Heer & Morera, 2009). It stands to reason that improving body satisfaction through physical exercise can improve emotional health and wellbeing.


Test yourself !

Can exercise affect emotion ?

True
False

Using exercise to regulate negative emotion

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[Provide more detail]

How can exercise be incorporated into everyday life as a mechanism for regulating negative emotion?

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Based on what we have discovered about the potential effects of physical exercise on negative emotions it is important to explore how these concepts can be incorporated into everyday life in order to improve mental health outcomes. Research suggests that simple steps can be taken in order to receive the emotional wellbeing benefits of physical exercise.

Intensity

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Craft and Landers (1998) compared the effects of light, moderate and intense aerobic and anaerobic exercise on the treatment of depression. The results of their study indicated that there was not a significant difference between anaerobic and aerobic exercise but did show that moderate exercise was most effective in the treatment of clinical depression Craft & Landers (1998). These findings are supported by other meta analytical studies (Netz et. al., 2005). The research suggests that high intensity exercise results in increased levels of pain and anxiety which have a negative moderating impact on emotional wellbeing and low intensity exercise does not produce significant effects. Data also suggests that exercise of two high intensity may punish exercising behaviours, reducing their occurrence, as well as contribute to negative emotional evaluations of the experience (Oldridge et al., 1983).

Type

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Studies have found support for both aerobic and anaerobic exercise, however the majority of existing research has explored and supported aerobic exercise (Dunn et al., 2005). The recommended levels of exercise for physiological effects suggest 30 minutes of moderate cardiovascular exercise, such as walking, per day (Australian Government Department of Health, 2014). Walking for 30 minutes is considered an effective way of reducing the symptoms of both depression and anxiety (Morgan et al., 2013).

Frequency and duration

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Hassmén, Koivula and Uutela, (2000) identified that exercising two to three times per week was most effective in moderating anger, sadness, depression, distrust and anxiety. Meta analytical studies indicate that 9-12 weeks of physical activity were more effective than shorter durations (Craft & Landers, 1998). Subsequent studies have also provided support for a 12 week duration in order to see effective results on emotional health (Annesi, 2000).

General recommendations

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The research appears to indicate that no singular method of exercise is recommended to achieve mental health benefits and rather participation in exercise in any form is beneficial. Increasing physical exercise participation is an area of study that is growing in importance (Dishman & Buckwort, 1996; Kahn et al., 2002). The data appears to indicate that participation[spelling?] is reinforced and maintained by social support (Calfas et al., 1996; King & Frederiksen, 1984) as well as rewards from intrinsic motivation that stems from improved self perception (Van Camp & Hayes, 2012). In order to improve your participation and frequency of physical exercise it is recommended to engage peers, friends or family to build a supporting social network.

Conclusion

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Physical exercise plays an important role in regulating negative emotions. Incorporating physical exercise into daily life will help people to improve their mental and physical wellbeing. Physical exercise incorporates more than just a clinical tool but a method for improving function in every day life. Exercise provides a simple and effective way of improving psychological wellbeing.

See also

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References

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