Social influence looks at how behaviour can be changed through pressures from others within a social context, once this pressure is understood it can be in turn used to influence participation in physical activity and exercise (Darlow & Xu, 2011). In exercise it has been shown how when the social pressures within an exercise group be it in a gym setting or a more social setting, social influence plays a role in participation and effort (Yuna & Silkb, 2011). Exercise is known generally as being a healthy behaviour with many benefits both physically and mentally (Bishop-Bailey, 2013). It has been found that some individuals become addicted to exercise and physical activity, making it a compulsion to engage in excessive exercise frequently leading to both psychologically and physiological impairing (Gapin et al. 2009). There are many names for this phenomena such as exercise dependence, exercise addiction, obligatory exercise, compulsive athleticism, compulsive exercising, and exercise abuse (Lichtenstein et al. 2014). As stated exercise can be addictive and in a social settings with pressures to participate with maximal effort in conjunction with others, can exercise addiction be fuelled in this setting if so what are the issues it raises. But is this pressure always a negative there can be positive as well, in order for treat exercise addiction social influence and assistance is vital.

There are multiply similarities between exercise addiction and drug addiction, the similarities include effects on tolerance, mood and withdrawals (Brown et al. 2010). The neurotransmitters which is the brains reward system is key in exercise and other addictions. An example of such a neurotransmitter is dopamine which has been found to be key in the brains rewarding system, a studies have been shown that regular excessive exercise can influence these sections of the brain which involve dopamine (Tanaka et al. 2009). As with many addictions exercise has symptoms, these symptoms in exercise addiction can be both mental and physical (Krivoschekov & Lushnikov, 2011). Once these symptoms arise within an exercise group, the group may see them as just the norms of exercise and pressure can be applied in order for the symptoms to be pushed aside and continue to exercise, as within the social context of the exercise group these maybe seen as the norms (Johnston et al. 2011). The symptoms of exercise addiction range across many fields and in terms of behaviour each person will react differently to situations. These behaviour can include a person’s desire to control their body both its weight, shape and size (Kiadó, 2012). It has been found that the main motivation in this strive and desire is to achieve the exercise induced “high”. This “high” is translated across many sports with many different phrases, in weight lifting it is described as “the pump” in long distance running its referred to as “the runners high” although it has different names and terminology it is the same euphoric feeling (Dishman & O’Connor, 2009). This euphoric state can become addictive and is a part of exercise addiction draws into compulsion. The social group setting of exercise applies pressure to members of the group when discussing this “high” other who may not have of experienced it will feel a need to experience this euphoria by further pushing themselves within exercise to reach this state. Pressure to adhere to exercise no matter how excessive within a social group setting mean that individuals meet the norms of the group and these norms within a this social setting maybe quite different from them of general society (McGrath, O’Malley, & Hendrix, 2011). The social pressures in the group depend on the norms of the groups, the positive effects of continuous exercise mentally and physically are well known and documented, but within the group if these positive effects are distorted to meet internal goals which are difficult to achieve the process of achieving them can become addictive (Wilson et al. 2012). There are factors which can affect the group’s persuasive powers on an individual’s thoughts feelings and behaviours in terms of exercise (Carron et al. 1996).  There have been a few methods put forward when it comes to measuring exercise addiction through questionnaires, but Hausenblas and Downs (2002a) identified some problems with these questionnaires. They found they can indirectly measure addiction through withdrawal symptoms, they were too specific in their focus meaning they were fixed on one activity (e.g. cycling, running, weightlifting), they discover how most questionnaires failed to provide a definition of exercise addiction and did not distinguish between primary or secondary dependence of the addiction and they were not theory driven so had no conceptual basis.

Chapman and De Castro (1990) developed the first method of identifying exercise addiction with their Running Addiction Scale (RAS) which has been used in other studies directed at running (Aidman and Woollard, 2003). From their review Hausenblas and Downs (2002b) developed the 21-item Exercise Dependence Scale (EDS). This scale can be used to determine and categorised exercise addiction into three categories, these are ‘at risk for exercise dependence’, ‘nondependent symptomatic’, or ‘non-dependent-asymptomatic’ groups. One limitation of this scale is that it does not distinguish between primary and secondary exercise dependence Hausenblas and Downs (2002b).There is no precise way to measure social influence there have been many theories put forward to explain social influence, these theories along with theories of exercise addiction will further look to draw conclusions to the effect they can have on exercise groups.

The social cognitive theory (Bandura, 1986) was developed with an emphasis on the acquisition of social behaviours, social cognitive theory continues to emphasise that learning occurs in a social context and that much of what is learned is gained through observation. This is turn can help to show how exercise behaviour can be influenced by human cognition and external stimuli, this can play a role in exercise behaviour within groups (Annesia et al. 2011). This feeds into Orfords (2001) model of addictive behaviours called The Social Behavioural Cognitive Moral Model of Excessive Appetites, Orford preferred the term appetite in place of addictive. This model looked at how a person’s involvement in an addictive behaviour can come about due to some factors which include personality, opportunities to take part in the activity and the normative influence of friends (Orford, 2001). This looks at the influence of friends or leaders in exercise groups, Parastatidou et al. (2012) looked at how this theory can be used to explain how adherence levels increase when involved in an exercise group, this looks at how social influence plays a role in exercise groups. Mónoka et al. (2012) discovered in his studies on exercise addition once it becomes a behaviour within a close groups can spread to others as the beliefs, goals and attitudes can change. In this group setting the Theory of Planned Behaviour can play a role with how the control over the situations within the exercise setting can become more controlling (Hagger et al. 2010). This theory can show how a favourable attitude towards exercise can happen due to pressure within a group, this attitude change can be to one of an addictive nature with exercise due to the group’s beliefs, norms and pressures (Prochaska, 2013).

The “high” discussed earlier obtained through exercise can influence the addiction process, this is can be seen in the Stimulus Response Theory through positive reinforcement of the “high” and also from within the exercise groups setting (Manzi et al. 2009). The positive intrinsic reinforcements in studies have been said to be the “high”, increased self-efficacy, more energy and increased confidence (Raichlen et al. 2012). The extrinsic reinforcements can be praise from others or compliments, within an exercise groups these extrinsic reinforcement can lead to greater adherence to the exercise behaviours within the group (Kelley et al. 2013). Can the persuasion within a group effect an individual’s judgement towards exercise, the theory of reasoned action looks at how behaviour can be influenced by both the attitudes towards the behaviour and also the influence of social environment and general subjective norms on the behaviour. These social norms in an exercise group can be set by the leaders in the group and/or others held in high regard with the attitude they convey to the group (Fishbein & Ajzen, 2011). If these attitudes are of an addictive nature towards exercise this in turn can lead to the overall social norm on the group being one of the same (Cook et al. 2013). In the group the social facilitation theory of effort within the group in studies have shown how when being observed in the group by both peers and external observers perceived effort levels increases (Snyder, Anderson-Hanley, & Arciero, 2012).  These theories all look at the social influences which may push the group towards exercise addiction norms and behaviours, the conceptual model of group cohesion looks at how the group becomes a cohesive group showing how these previous theories can then become prevalent in the influence of exercise addiction in the exercise group (Jenkins & Alderman, 2011). This development of group cohesion has been shown to increase adherence, feelings of distinctiveness, group norms and making sacrifices for the group (Spink et al. 2013). Research into group cohesion has been based around Carron et al. (1985) conceptual model of group cohesion. This model states that there are two predominant categories of group cohesion. The first category is group integration this look at the member’s view on how the group functions as a unit (Carron, 1985), within the exercise group setting this can mean the group are achieving their goals both collectively and individually (Burkea & Shapcott, 2010). In terms of exercise addiction this category the individual leaders who are intensely and frequently exercising may feel that others need to be matching the example they set (Weinberg & Gould, 2010). The second category is individual attraction and this reflects how attractive the groups is to an individual (Carron, 1985), within an exercise group this can explain the adherence to the group as the exercise addiction is the groups norm, therefore external norms against the addiction are not a prevalent (Weinberg & Gould, 2010). These two categories are further divided into two more categories, task and social cohesion. Task cohesion involves the degree to which members will work together to achieve group goals, this can involve many facets within an exercise group such as motivation, education and drive (Caperchione et al. 2011). Social cohesion looks at the relationships within the group and if member’s like each other and the social interactions, in an exercise group with exercise addiction as a driving force the social relationships are formed through exercise (Pitkala et al. 2011). These theories and models looked at the group’s ability to become cohesive and how exercise can become an addiction in some situations. This information looked at the group and its influences on its members as well as how the addiction may spread across the group to become an acceptable norm, within this new norm there are positive and negative pay offs to the addiction (Weinberg & Gould, 2010).

Exercise has psychological benefits such as stress reduction, prevent cognitive decline, increased relaxation, increased self-confidence and alleviate anxiety to name a few (Hogan, Mata, & Carstensen, 2013). In a study by Ruby et al. (2011) another benefit to exercise is the ability for it to control addiction, it was stated that the release of dopamine during exercise helps to reduce addiction in other fields such as drugs and alcohol which release the chemical dopamine. Weinstein and Weinstein (2014) investigated how this release of dopamine can not only control addiction but become itself an addiction. Thayer (1989) produced a two dimensional model of mood and its link with general bodily arousal which includes conscious components of energy and tension. This model is applicable as it shows how the psychological benefits involved with arousal states later researched by Sakairi et al. (2013), looks at how self-regulation of mood state can be obtain through exercise, reaching their optimal mood state. It has been shown that exercise can benefit moods (Johansson et al. 2011) and change emotions (Zi-xin & De-long, 2011) both in terms of pleasant and unpleasant emotions. These positive and negative changes in emotions and mood states can contribute to the “high” experience within exercise (Anderson & Brice, 2011), part of this feeling can carry into post exercise recovery and even beyond with the levels of unpleasant emotions and negative mood factors such as anxiety reduce due to exercise (Hamer, Endrighi, & Poole, 2012). The individuals experiences in exercise plays a role in how they perceive exercise, many group based studies have confirmed that there are psychological benefits which occur as a result of exercise (e.g. Rasmussen & Laumann 2013, Cruise et al. 2011 and Morgan & Goldston, 2013). These theories however have not paid attention to the individuals own unique experiences, the reversal theory can be used to predict exercise motivation and also experience (Brown, 1988). The reversal theory considers human behaviour is inherently inconsistent looking at the basis of human emotion, personality and motivation (Brown, 1988). Glasser (1976) looked at exercise and its general positive correlation with good health termed exercise as a “positive addiction” comparing exercise to more destructive addictions which had more severe consequences, later research however looked at the negative consequences of exercise addiction (Cook, Hausenblas, & Freimuth, 2014). The psychological benefits of exercise can aid participants in exercise but the benefits can also fuel exercise addiction (Lynch et al. 2013), the negative psychological consequences linked with exercise addiction have been proven to damage an individual both physically and mentally (Kiadó, 2014).  Studies into social aspects of exercise addiction have shown that close relationships are pushed aside and deteriorate as the exercise regime does not allow for deviation (McNamara & McCabe, 2012), this behaviour has been shown in a group setting with similar goals and norms to encourage participation in the group activates isolating relationships and distractions outside of the groups norms (Meyer, 2011). Another consequences of exercise is injury, but in cases of exercise addiction it has been shown that athletes will exercise regardless of the injury or the pain (Lichtenstein et al. 2014). This can lead to the body not healing properly and in time this can limited the abilities of the individual, for a person who is involved in a groups who’s norm incorporate exercise addiction this can lead to depression form lack of ability to exercise (Heyman et al. 2012). Direct correlation between exercise addiction and depression have be shown to affect individuals who cannot meet the expectations of others in a group (Grandi et al. 2011), social facilitation plays a role in the individual exerting maximal effort and not meeting this level of perceived effort can lead to depression (Kiadó, 2013). Eating disorders are a major issue with people involved in in exercise but this issue increases dramatically with exercise addiction (Yates, 2013). In a group setting eating disorders are quite prevalent with leaders perceived in a group to have an ideal weight or body composition influences poor eating behaviours which have been shown to influence to group (Cook et al. 2011). There are many types of eating disorders to increase rapid body changes such as anorexia nervosa and bulimia nervosa, in women who lose too much body fat rapidly can suffer from Amenorrhea which affects the menstrual cycle (Fietza, Touyz, & Hay, 2014). These eating disorders can lead to many other issues in both genders with anorexia physical damages are highly dangerous these include an irregular heartbeat, liver damage, muscle wasting, dehydration, malnutrition and sleep disturbances to name a few (Arcelus et al. 2011). All of these damages can lead to a lowered immune system, meaning the individual is more susceptible to illness and infection. Due to the severity of these damage to eating disorders it is important to try and identify them early on before damages become increasingly dangerous.

The Eating Attitudes Test (EAT) developed by Gamer and Garfinkel (1979) and the Eating Disorder Inventory (EDI) developed by Gamer and Olmsted (1984) measure and identify eating disorders with individuals, the reason for choosing these identifiers is there link with exercise in there testing (Rivasa et al. 2010). These disorder play a huge role in exercise addiction and how a group may influence such behaviours on some of its members through unjustified and delusional diet plans (Rohde et al. 2014). Exercise addiction as seen from information above as dangerous consequences once it is attached to a groups norms and individuals take part within the group are influenced to adhere to the norms, once an individual is addicted to exercise and intervention has been seen to be the best solution to alter this behaviour (Landolfi, 2013). The assignment has looked conclusively at exercise addiction and how groups can affect this addiction in other, also how exercise can be a secondary dependence where exercise can be secondary to an eating disorder or vice versa (Cook et al. 2013). Brown’s (1997) model and primary exercise dependence look at exercise addiction broken into sections to give a better understanding of the addiction and this in turn help to discover how to treat the addiction through understanding, this model looks into how the addiction is established and the cycles which affect individuals. Changing an individual with exercise addiction behaviours can be difficult because it has become a crucial part of their hedonic tone which is the experience of pleasurable mood and emotional states (Bruce et al. 2014), this means the behaviour is difficult to extinguish. Cutting down on exercise will be extremely difficult (Darlow & Xu, 2011), however if the individual changes activity from their primary one and cuts down slightly such as increased rest days this has been shown to help with the addiction as well as changing the time of day for exercise which breaks up the routine (Glasner-Edwards & Rawson, 2010). Education from outside of their exercise group form trained professionals on how rest days and proper nutrition (Veasey et al. 2013) can help them to healthy reach their target goals through safe and proven methods without long term consequences to mental and physical health (Epling & Pierce, 2013). Study into treatment for addiction stressed how clinical psychology in most extreme cases is required to help in dealing with the addiction. Through Browns (1997) model West & Brown (2013) look at how in the treatment of exercise addiction it is key for the individual to become more aware of the renforcement process of their behaviour leading to changes in personal decision making, they stated that the individuak must become more tolerant of short stages of unpleasent hedonic tone. This can lead to an ability to manipulate the hedonic tne but as found in the works of Kurimayet al. (2013) this can take up to seven years. The changes can be monitor through the continuous quality improvement (CQI) in Addiction Treatment Settings (Hunter et al. 2011).

In conclusion the assignment looks into social influence and its effects on exercise addiction in group exercise, looking at social influence (Lichtenstein et al. 2014) and exercise addiction (Dishman & O’Connor, 2009) separately then linking them together through various theories and studies. It is explained why individuals may become addicted to exercise either by the chemical releases (Tanaka et al. 2009) and personal experiences (Spink et al. 2013) or by the influence of others/leaders in an exercise group who’s norms accept the consequences of exercise addiction (Parastatidou et al. 2012). These consequences as detailed above affect the individual both mentally and physically in detrimental ways (Rivasa et al. 2010), with a look into proven methods of addiction treatment through different methods and techniques. The assignment looks into the affects a group can have on exercise addiction and how the addiction itself affects individuals, giving a revised and explored method of treatment.

ReferencesShow all

Aidman, E. V. (2003). The influence of self-reported exercise addiction on acute emotional and physiological responses to brief exercise deprivation. Psychology of Sport and Exercise, 225-236.

Anderson, R. J., & Brice, S. (2011). The mood-enhancing benefits of exercise: Memory biases augment the effect. Psychology of Sport and Exercise, 79-82.

Annesia et al., J. J. (2011). Effects of The Coach Approach Intervention on Adherence to Exercise in Obese Women. Research Quarterly for Exercise and Sport, 99-108.

Arcelus, J. A. (2011). Mortality Rates in Patients With Anorexia Nervosa and Other Eating Disorders. Arch Gen Psychiatry, 724-731.

Bandura, A. (1986). Social foundations of thought and action: A social cognitive theory. Englewood Cliffs, NJ: Prentice- Hall, Inc.

Bishop-Bailey. (2013). Mechanisms governing the health and performance benefits of exercise. British Journal of Pharmacology, 1153–1166.

Brown et al., R. A. (2010). A pilot study of aerobic exercise as an adjunctive treatment for drug dependence. Mental Health and Physical Activity, 27-34.

Brown, R. I. (1988). ‘Reversal theory and subjective experience in the explanation of addiction and relapse'. Amsterdam: Elsevier.

Brown, R. I. (1997). ‘A theoretical model of behavioural addictions – Applied to offending’,. New York: Wiley.
Bruce, T. J. (2014). The Addiction Treatment Planne. Sussex: UK: John Wiley & Sons.

Burkea, S. M., & Shapcott, K. M. (2010). Group goal setting and group performance in a physical activity context. International Journal of Sport and Exercise Psychology, 245-261.

Caperchione, C. W. (2011). Investigating the relationship between leader behaviours and group cohesion within women's walking groups. Journal of Science and Medicine in Sport, 325-330.

Carron et al., H. M. (1996). Social influence and exercise: a meta-analysis. Journal of Sport & Exercise Psychology , 1-16.

Carron, A. W. (1985). ‘The Development of an Instrument to Assess Cohesion in Sport Teams: The Group Environment Questionnaire’,. Journal of Sport Psychology, 244-266.

Chapman, C. L. (1990). Running addiction: Measurement and associated psychological characteristics. Journal of Sports Medicine, 283-290.
Cook, B. ,. (2011). Eating disorders and exercise: A structural equation modelling analysis of a conceptual model. European Eating Disorders Review, 216-255.

Cook, B., Hausenblas, H., & Freimuth, M. (2014). Exercise Addiction and Compulsive Exercising: Relationship to Eating Disorders, Substance Use Disorders, and Addictive Disorders. Eating Disorders, Addictions and Substance Use Disorders, 127-144.

Cook, B., Karrv, T. M., Zunkerv, C., Mitchell, J. E., Thompson, R., Sherman, R., . . . Wonderlich, S. A. (2013). Primary and Secondary Exercise Dependence in a Community-Based Sample of Road Race Runners. Journal of Sport & Exercise Psychology, 50-62.

Cruise, K. E. (2011). Exercise and Parkinson’s: benefits for cognition and quality of life. Acta Neurologica Scandinavica, 3-19.

Darlow, S. D., & Xu, X. (2011). The influence of close others’ exercise habits and perceived social support on exercise. Psychology of Sport and Exercise, 575–578.

Dishman, R. K., & O'Connor, P. J. (2009). Lessons in exercise neurobiology: The case of endorphins. Mental Health and Physical Activity, 4-9.

Epling, F., & Pierce, D. (2013). Activity Anorexia: Theory, Research, and Treatmen. Psychology Press.

Fietza, M., Touyz, S., & Hay, P. (2014). A risk profile of compulsive exercise in adolescents with an eating disorder: a systematic review. Advances in Eating Disorders: Theory, Research and Practice, 12-16.

Fishbein, M. I. (2011). Predicting and Changing Behavior: The Reasoned Action Approach. New York, NY: Taylor and Francis Group.

Gapin et al., J. L. (2009). The Relationship Between Frontal Brain Asymmetry and Exercise Addiction. Journal of Psychophysiology, 135-142. doi:10.1027/0269-8803.23.3.135

Garner, D. M. (1979). The Eating Attitudes Test: An index of the symptoms of anorexia nervosa. Psychological Medicine, 273-279.

Garner, D. M. (1984). Eating Disorder Inventory manual. Odessa: FL: Psychological Assessment Resources.

Glasner-Edwards, S., & Rawson, R. (2010). Evidence-based practices in addiction treatment: Review and recommendations for public policy. Health Policy, 93-104.

Grandi et al. Silvana, C. C. (2011). Personality characteristics and psychological distress associated with primary exercise dependence: An exploratory study. Psychiatry Research, 270-275.

Hagger, M. S. (2010). Self-regulation and self-control in exercise: the strength-energy model. International Review of Sport and Exercise Psychology, 62-86.

Hamer, M., Endrighi, R., & Poole, L. (2012). Physical Activity, Stress Reduction, and Mood: Insight into Immunological Mechanisms. Psychoneuroimmunology Methods in Molecular Biology, 89-102.

Hausenblas, H. A. (2002a). Exercise dependence: A systematic review. Psychology of Sport and Exercise, 89-123.

Hausenblas, H. A. (2002b). How much is too much? The development and validation of the Exercise Dependence Scale. Psychology and Health, 387-404.

Heyman, F.-X. G. (2012). Intense exercise increases circulating endocannabinoid and BDNF levels in humans—Possible implications for reward and depression. Psychoneuroendocrinology, 844-851.

Hogan, C. L., Mata, J., & Carstensen, L. L. (2013). Exercise holds immediate benefits for affect and cognition in younger and older adults. Psychology and Aging, 587-594.

Hunter et al., S. B. (2011). Continuous Quality Improvement (CQI) in Addiction Treatment Settings. New York: BioMed Central Ltd.

Jenkins, J. M., & Alderman, B. L. (2011). Influence of Sport Education on Group Cohesion in University Physical Education. Journal of Teaching in Physical Education, 214-230.

Johansson, M. P. (2011). Acute Effects of Qigong Exercise on Mood and Anxiety. Sport, Exercise, and Performance Psychology, 60-65.

Johnston et al. Olwyn, J. R. (2011). Excessive exercise: From quantitative categorisation to a qualitative continuum approach. European Eating Disorders Review, 237-248.

Mónoka, K. B. (2012). Psychology of Sport and Exercise. Psychometric properties and concurrent validity of two exercise addiction measures: A population wide study, 739-746.

Kiadó, A. (2012). Exercise dependence among customers from a Parisian sport shop. Journal of Behavioral Addictions, 28-34. doi:10.1556/JBA.1.2012.1.3

Kiadó, A. (2013). The exercise paradox: An interactional model for a clearer conceptualization of exercise addiction. Journal of Behavioral Addictions, 199-208.

Kiadó, A. (2014). Muscle dysmorphia: Could it be classified as an addiction to body image? Journal of Behavioral Addictions, 2062-2071.

Krivoschekov, S. G., & Lushnikov, O. N. (2011). Psychophysiology of sports addictions (exercise addiction). Human Physiology, 509-513.

Kurimay, T. M. (2013). Exercise Addiciton: The Dark Side of Sport. Clinical Sports Psychiatry: An International Perspective, 33-36.

Landolfi, E. (2013). Exercise Addiction. Sports Medicine, 111-119.

Lejoyeux et al. Michel, C. G. (2012). Exercise dependence among customers from a Parisian sport shop. Journal of Behavioral Addictions, 28-34.

Lichtenstein et al., E. C. (2014). Validation of the exercise addiction inventory in a Danish sport context. Scandinavian Journal of Medicine & Science in Sports, 447-453. doi:DOI: 10.1111/j.1600-0838.2012.01515.x

Lichtenstein, M. B. (2014). Exercise addiction: A study of eating disorder symptoms, quality of life, personality traits and attachment styles. Psychiatry Research, 410-416.

Lynch, W. J. (2013). Exercise as a novel treatment for drug addiction: A neurobiological and stage-dependent hypothesis. Neuroscience & Biobehavioral Reviews, 1622-1644.

Manzi, V. C. (2009). Dose-response relationship of autonomic nervous system responses to individualized training impulse in marathon runners. American Journal of Physiology, 3-9.

McGrath, J. A., O’Malley, M., & Hendrix, T. J. (2011). Group exercise mode and health-related quality of life among healthy adults. Journal of Advanced Nursing, 491-500.

McNamara, J., & McCabe, M. P. (2012). Striving for success or addiction? Exercise dependence among elite Australian athletes. Journal of Sports Sciences, 755-766.

Meyer, C. ,. (2011). Compulsive exercise and eating disorders. European Eating Disorders Review, 174-189.

Morgan, W. P., & Goldston, S. E. (2013). Exercise And Mental Health. New York: Taylor & Francis.

Parastatidou, I. S. (2012). Addicted to Exercise. European Journal of Psychological Assessment, 3-10.

Pitkala, K. H. (2011). Effects of Socially Stimulating Group Intervention on Lonely, Older People's Cognition: A Randomized, Controlled Trial. The American Journal of Geriatric Psychiatry, 654-666.

Prochaska, D. J. (2013). Transtheoretical Model of Behavior Change. New York: Springer.

Raichlen, D. A. (2012). Wired to run: exercise-induced endocannabinoid signaling in humans and cursorial mammals with implications for the ‘runner’s high’. The Journal of Experimental Biology, 1331-1336.

Rasmussen, M., & Laumann, K. (2013). The academic and psychological benefits of exercise in healthy children and adolescents. European Journal of Psychology of Education, 949-962.

Rivasa, T. R. (2010). The Eating Attitudes Test (EAT-26): Reliability and Validity in Spanish Female Samples. The Spanish journal of psychology, 1044-1056.

Rohde, P. E. (2014). Development and predictive effects of eating disorder risk factors during adolescence: Implications for prevention efforts. International Journal of Eating Disorders, 12-19.

Ruby, M. B., Dunn, E. W., Perrino, A., Gillis, R., & Viel, S. (2011). The invisible benefits of exercise. Health Psychology, 67-74.
Sakairi, Y. K. (2013). Development of the Two-Dimensional Mood Scale for self-monitoring and self-regulation of momentary mood states. Japanese Psychological Research, 338-349.

Snyder, A. L., Anderson-Hanley, C., & Arciero, P. J. (2012). Virtual and Live Social Facilitation While Exergaming: Competitiveness Moderates Exercise Intensity. Journal of Sport & Exercise Psychology, 252-259.

Spink, K. S. (2013). Group cohesion and adherence in unstructured exercise groups. Psychology of Sport and Exercise, 4-8.
Strohacker, K. O. (2013). The Impact of Incentives on Exercise Behavior: A Systematic Review of Randomized Controlled Trials. Annals of Behavioral Medicine, 28-32.

Tanaka et al., K. ,. (2009). Benefits of physical exercise on executive functions in older people with Parkinson’s disease. Brain and Cognition, 435–441.

Veasey et al. R.C., J. G. (2013). Breakfast consumption and exercise interact to affect cognitive performance and mood later in the day. A randomized controlled trial. Appetite, 38-44.

Weinberg, R. S., & Gould, D. (2010). Foundations of Sport and Exercise Psychology 5th Edition. Champaign, IL: Human Kinetics.

Weinstein, A. W. (2014). Exercise Addiction- Diagnosis, Bio-Psychological Mechanisms and Treatment Issues . Current Pharmaceutical Design, 8-14.

West, R., & Brown, J. (2013). Theory of Addiction. Sussex: UK: John Wiley & Sons.

Wilson, A. J., & Mary E Jung, A. C. (2012). Effects of a group-based exercise and self-regulatory intervention on obese adolescents’ physical activity, social cognitions, body composition and strength: A randomized feasibility study. Journal of Health Psychology, 1223-1239.

Yates, A. (2013). Compulsive Exercise And The Eating Disorders: Toward An Integrated Theory Of Activity. New York: Routledge.

Yuna, D., & Silkb, K. J. (2011). Social Norms, Self-identity, and Attention to Social Comparison Information in the Context of Exercise and Healthy Diet Behavio. Health Communication, 275-285.

Zi-xin, Z., & De-long, D. (2011). Relationship between exercise cognition,emotion and competition performance. Journal of Wuhan Institute of Physical Education, 12-15.