Abstract
Regular physical activity can support long-term health maintenance, e.g., by reducing inflammatory markers such as C-reactive protein (CRP) levels. However, excessive physical activity can promote the development of both mental and physical illness as well. From a psychological perspective, excessive exercise can lead to the development of exercise addiction (EA) and athlete burnout (AB). However, EA and AB have been rarely investigated so far and it is still unknown whether they are associated with risk factors for physical diseases such as increased CRP levels. In our study, we investigated whether EA and AB in endurance athletes are associated with CRP concentrations. Furthermore, sex differences and prevalence rates of EA were investigated. Ninety-five endurance athletes participated (54.7% female, mean age = 31.8 ± 15.02 years). CRP levels were assessed by means of Dried Blood Spots. For EA and AB assessment, the Exercise Addiction Inventory (EAI) and the Athlete Burnout Questionnaire (ABQ) were used. Exercise addiction was negatively associated with CRP in men. No associations were found for women. None of the ABQ subscales (physical and emotional exhaustion, devaluation of sports, and reduced sense of accomplishment) was associated with CRP levels or with EA. Prevalence of EA was 4.2%. More than 80% of the participants were at risk for EA development. Our results suggest that EA is not necessarily associated with a higher risk for physical diseases through inflammatory pathways. However, EA is a serious mental illness that is widespread in athletes, at least at a subclinical level.
Highlights
Regular physical activity (PA) usually has a positive connotation and is widely associated with promoting mental and physical health (Alfermann and Stoll, 1997; Graf et al, 2004; Stoll and Ziemainz, 2012)
Four (4.2%, 2 male, 2 female) of the participants were classified as exercise addicted, who met the criterion of an Exercise Addiction Inventory (EAI) score ≥24
C-reactive protein (CRP) levels were significantly different between the three EAI groups [F(2,92) = 3.72, p = 0.028; Figure 1B]
Summary
Regular physical activity (PA) usually has a positive connotation and is widely associated with promoting mental and physical health (Alfermann and Stoll, 1997; Graf et al, 2004; Stoll and Ziemainz, 2012). Exercise addiction is—just like other addictions—accompanied by withdrawal symptoms if too long breaks are taken, tolerance development, and loss of control (Breuer and Kleinert, 2009; Ziemainz et al, 2013; Stoll, 2017). Regardless of competition ambitions, there is an inner constraint to do sports. It is mainly discussed whether EA should be classified as an addiction in the sense of a substanceindependent dependency, an obsessive-compulsive disorder, or an impulse control disorder. Especially substance dependencies, have been found to be related with an increase in inflammatory markers such as C-reactive protein (CRP; Reece, 2012; Costello et al, 2013). The associations between substanceindependent addictions (such as EA) and CRP levels are not yet fully understood
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
