Depression and stress in German competitive athletes: From basic research to preventive interventions for adolescent athletes

Depression is a common mental health disorder among competitive athletes that can have detrimental consequences including performance-decline, premature career-dropout, and even suicide. Athletes have been found to be as susceptible to depressive symptoms as non-athletes, and stress has repeatedly been linked to depression in the context of competitive sports. Based on the serious potential consequences of depression in competitive sports, the present dissertation explores depression and stress, and factors associated therewith, in German competitive athletes.

An overview of the current body of literature reveals that existing prevalence studies on depression report a broad range of prevalence rates and inconsistent findings regarding the association between depressive symptomatology and demographic variables (e.g., age, level of sport performance). Several of the existing prevalence studies are further characterized by methodological limitations, such as small and unrepresentative sample sizes, and the disregard of the adolescent athlete population. With the intention of addressing the aforementioned limitations of, and research gaps in, prior studies, the aim of study I of this dissertation is the investigation of the prevalence of depressive symptoms in a comprehensive sample of German competitive athletes. A special focus is placed on the examination of the association between the demographic variables age, gender, and level of sport performance and the prevalence of depressive symptomatology. Study I reveals that of 1,799 German competitive athletes, 13.4% were screened positively for depression and 10.2% for impairments in psychological well-being. Adolescent age, female gender, and junior national team status were identified as risk factors for depressive symptoms.

For the general population, empirical support for the relationship between depression, stress, and back pain is extensive. Despite the fact that back pain is a widespread issue in competitive sports with adverse performance and (mental) health outcomes for athletes, the relationship between the factor back pain and the psychosocial variables depression and stress has hardly received any scientific attention in competitive sports. To close this research gap, study II of this dissertation investigates the relationship between depression, stress, and back pain in German competitive athletes. Study II reveals that depression and stress are associated with back pain parameters in a population of 154 competitive athletes with back pain. In particular, stress could be linked to pain intensity and depression to pain-related disability.

A multitude of empirical findings supports the assumption that adolescence is a sensitive period for the experience of stress and stress-related mental (e.g., depression) and physical (e.g., back pain) health outcomes. In order to transfer knowledge derived from empirical findings and theoretical frameworks to the applied work with competitive athletes, the aim of study III is to develop, implement, and evaluate a theory-based stress-prevention intervention for 92 adolescent soccer players through a randomized controlled trial. The intervention was evaluated on its effectiveness regarding stress, coping, and depression parameters and on its perceived usefulness according to the athletes. No intervention effects on stress, coping, and depression emerged. Notwithstanding, the athletes perceived the stress-prevention intervention to be useful, especially with regard to the improvement of their performance and well-being.

This dissertation provides new insights into depression, stress, and factors associated therewith in competitive sports by means of basic research via cross-sectional designs (study I and study II) and a longitudinal preventive intervention study (study III). Considering the average prevalence rate across all three studies, every 10th German competitive athlete was screened positively for depressive symptoms. This observed prevalence rate of depressive symptoms in competitive athletes is akin to the prevalence rate detected in the general German population. This dissertation further indicates that adolescent athletes seem to be more vulnerable to depressive symptomatology than other age groups. Forthcoming studies should consider investigating the mechanisms of stress and stress-related conditions in competitive sports to improve the understanding of their etiology and to deduce effective preventive interventions for the context of competitive sports in general, and for the adolescent athlete population in particular.