Exercise addiction and COVID-19-associated restrictions

The coronavirus disease 2019 (COVID-19) pandemic has brought a new reality in every area, including sports. The shutting down of gyms, swimming pools, and fitness centres, postponement of sporting events, and closure of non-emergency physical therapy services, along with the practice of self-isolation, quarantine, and social distancing, as well as restrictions on outdoor activities and exercises, may eventually have physical, psychological, and behavioural consequences to the population. Under such unusual circumstances, many individuals struggle to maintain physically active lifestyles. Therefore, alterations in habits and routine activities, including mobility, exercise, and physical activity, are necessary.

There is growing evidence that a beneficial relationship between exercise and immunity in recreational individuals (J-shaped curve) and elite athletes (S-shaped curve) (Nielsen, 2013; Schwellnus et al., 2016). Regular exercise enhances rather than suppresses the immune response in individuals of all ages and a physically active lifestyle may delay or limit the aging of the immune system, leading to a reduced risk of contracting communicable diseases (e.g. viral and bacterial infections) and non-communicable diseases (e.g. diabetes, hypertension, and cancer) (Campbell & Turner, 2018). Given the hypothesis that moderate training load is associated with lower risks of contracting illness, certain individuals may push themselves to keep fit and stay in shape by doing exercises (Chamorro-Viña et al., 2013). Originally aimed at preventing the transmission of COVID-19, some people might risk adapting this new lifestyle by overdoing exercise and developing an unhealthy obsession with physical fitness and exercise. During the COVID-19 lockdown, these individuals may exercise excessively considering a more flexible schedule with work from home, more free time, less travel, and also public health encouragement to take regular exercise.

Exercise and sports activities yield a favorable health and mental impact when performed in moderation (Lim & Pranata, 2020). Scientific evidence explains that exercise triggers the release of dopamine and endorphin, which are neurotransmitters that play in the “joy and reward” system and, therefore, induces a euphoric feeling while relieving stress. However, excessive exercise may be detrimental both physically and psychologically. Psychological studies define exercise addiction in terms of reward, habituation, social support, mood alteration, stress alleviation, anxiety reduction, and avoidance of withdrawal (Freimuth et al., 2011; Weinstein & Weinstein, 2014). Egorov and Szabo (Egorov & Szabo, 2013) highlighted theoretical models for exercise addiction, but the “four phases” model is the most widely recognised theory that begins with recreational exercise, then at-risk exercise, then problematic exercise, and, lastly, exercise addiction (Freimuth et al., 2011).

The exercise addiction syndrome is not a formal clinical diagnosis and is not listed as a disorder in the latest Diagnostic and Statistical Manual of Mental Disorders (DSM-5) (American Psychiatric Association, 2013), but rather a behavioural condition that often stems from other psychiatric disorders, particularly body dysmorphic disorder and eating disorder (Weinstein & Weinstein, 2014). Individuals with eating disorders are 3.7 times more likely to develop exercise addiction, while immoderate exercise is part of the diagnostic criteria for both anorexia and bulimia exercise (Trott et al., 2020). This addiction may also occur when in isolation (Hausenblas et al., 2017). Individuals with eating disorders are 3.7 times more likely to develop exercise addiction, while immoderate exercise is part of the diagnostic criteria for both anorexia and bulimia Sussman et al. (Sussman et al., 2011) estimated that 15% of exercise addicts have concurrent addiction to alcohol, cigarettes, or illegal drugs, while 25% may have other addictions (e.g. sex, shopping).

Substance abuse can be found simultaneously with exercise addiction, especially when these individuals want to achieve better performance but don’t feel they can do it without using performance-enhancing drugs. Competition participants are at increased risk of using substances such as anabolic steroids, cocaine, and protein-drinks, while non-sports practicing individuals are also found to use both addictive and performance-enhancing drugs. This group of individuals appear to have a greater risk of developing substance dependence syndrome (Franques et al., 2001). For some people, interruption to what seems excessive or addictive exercise may lead to increasingly damaging addictions, including alcohol use, increased aggression, and domestic violence. The combination of exercise dependence and substance abuse lead to harmful situations and detrimental health problems.

Defining exercise dependence is not easy considering the difficulty in explaining how much is too much, how to differentiate an exercise addict from a gym enthusiast, how to describe dedicated athletes who train rigorously preparing for the next event, and many more. According to the DSM-5 criteria for behavioural addiction, Hausenblas and Downs (Downs et al., 2004; Hausenblas & Downs, 2002) identified exercise addiction by the following criteria: increasing tolerance, withdrawal symptoms, lack of control, intention effects, excessive time spent in relation to exercise, reduction in other activities, and continuance despite creating physical, psychological, and/or interpersonal problems.

Abnormalities in reward and inhibition systems are found in exercise addicts, which may explain their impulsivity, loss of control, and interference in decision-making. In addicts’ brains, reward system overactivation is revealed by enhanced activities in the prefrontal, limbic, and striatal areas, while an impaired inhibition system is reflected by lower N2 and P3 amplitudes in the orbitofrontal-dorsolateral cortices (Huang et al., 2019). These individuals have to exercise more to trigger chemical release which describes reward-seeking behaviour. Meanwhile, an addiction-based conceptual model agreed by sports and exercise physicians and athletes features three components: learned (negative perfectionism), behavioural (obsessive-compulsive drive), and hedonic (self-worth compensation and decrease of negative affect and withdrawal) (Macfarlane et al., 2016).

A high prevalence of exercise addiction is found in athletes (e.g. runners, triathletes) (Corazza et al., 2019), with obsessive passion and dedication to sports considered as strong predictors (de la Vega et al., 2016). Training-associated risk factors (not only psychological factors) should be taken into account when identifying exercise dependence. Maceri et al. (2019) suggested that 25% of this condition could be predicted by the body mass index (BMI), weekly running frequency, number of years running, injury frequency, and athletic identity scores. It is worrying that high levels of exercise addiction found to negatively impact athletes’ performance in all branches of track and field (Çetin et al., 2020). Delay of sporting events and confinement of space may exacerbate athletes’ physical and psychological issues.

Whether exercise addiction can exist without a primary disorder is still questionable. During the COVID-19 lockdown, those who are not aware that they are exercise addicts may struggle with anxiety or panic attacks due to the inability to exercise outside, while simultaneously unable to overcome their underlying disorders. They end up exercising at home and may eventually realise what it feels like to exercise in moderation, how days without gym sessions can benefit themselves, and begin to loosen their attachment to the excessive exercise they have craved for.

Assessment and treatment should consider different stages of exercise addiction development and its comorbidities with coexisting psychiatric disorders (Weinstein & Weinstein, 2014). The Exercise Dependent Scale (EDS-R) (American Psychiatric Association, 2013; Downs et al., 2004), derived from modified criteria for substance dependence, and the Exercise Addiction Inventory (EAI) (Griffiths et al., 2005; Lichtenstein et al., 2018), based on Griffith’s modification of Brown’s model of addiction, have good validity and reliability as screening tools (Sicilia et al., 2018). Other measurement scales may be utilised depending on the type of sport (e.g. running). Assumed to encompass the obsessive-compulsive dimension, the management is based on cognitive-behavioural principles. In treating addiction, the goal is not to cease exercise but to exercise moderately, which is considered as a healthy habit. Furthermore, co-occurring disorders must be addressed to prevent relapse or complications from exercise dependence (Freimuth et al., 2011).

Self-control, as well as physical and psychological dedication, is crucial to combating exercise addiction. Avoidance of addictive substances is also helpful. With an unknown end date for this pandemic, exercising in moderation is highly recommended to boost immunity and reduce the risks of illness (Chamorro-Viña et al., 2013; Nielsen, 2013; Schwellnus et al., 2016). However, exercise or sports activities should regain the elements of play and fun and not be seen as a must-do. Recognising the four phases of exercise addiction is helpful for early identification and for guiding treatment.

Author Contributions

M.A.L developed the idea and wrote the manuscript.

Disclosure statement

The author declares that the research was conducted in the absence of any commercial or financial relationship that could be construed as a potential conflict of interest.