title: Markers of stress and inflammation as potential mediators of the relationship between exercise and depressive symptoms: findings from the TRAILS study.
abstract: The hypothalamic-pituitary-adrenal axis, autonomic nervous system, and immune system have been proposed to underlie the antidepressant effect of exercise. Using a population sample of 715 adolescents, we examined whether pathways from exercise to affective and somatic symptoms of depression were mediated by these putative mechanisms. Exercise (hours/week) and depressive symptoms were assessed at age 13.5 (± 0.5) and 16.1 (± 0.6). Cortisol and heart rate responses to a standardized social stress test and C-reactive protein levels were measured at age 16. Exercise was prospectively and inversely related to affective (B = -0.16, 95% CI = -0.30 to -0.03) but not somatic symptoms (B = -0.04, 95% CI = -0.21 to 0.13). Heart rate during social stress partially mediated this relationship (B = -0.03, 95% CI = -0.07 to -0.01). No other mediating effects were found. Hence, the autonomic stress system may play a role in the relationship between exercise and depressive symptoms.
authors.affiliation: Interdisciplinary Center Psychopathology and Emotion Regulation, Department of Psychiatry, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands.
authors.forename: Sanne H
authors.initials: SH
authors.lastname: Booij
authors.forename: Elisabeth H
authors.initials: EH
authors.lastname: Bos
authors.forename: Peter
authors.initials: P
authors.lastname: de Jonge
authors.forename: Albertine J
authors.initials: AJ
authors.lastname: Oldehinkel
mesh_terms: D000293:Adolescent; D001341:Autonomic Nervous System / Q000503:physiopathology; D015415:Biomarkers / Q000032:analysis; D002097:C-Reactive Protein / Q000032:analysis; D003863:Depression / Q000378:metabolism* / Q000503:physiopathology / Q000523:psychology; D015444:Exercise / Q000502:physiology / Q000523:psychology*; D005260:Female; D006339:Heart Rate / Q000502:physiology; D006801:Humans; D006854:Hydrocortisone / Q000032:analysis*; D007030:Hypothalamo-Hypophyseal System / Q000503:physiopathology; D007249:Inflammation / Q000378:metabolism* / Q000503:physiopathology / Q000523:psychology; D008297:Male; D010913:Pituitary-Adrenal System / Q000503:physiopathology; D011569:Psychiatric Status Rating Scales; D012463:Saliva / Q000737:chemistry; D013315:Stress, Psychological / Q000378:metabolism* / Q000503:physiopathology / Q000523:psychology
chemical_list: D015415:Biomarkers; D002097:C-Reactive Protein; D006854:Hydrocortisone
keywords: Adolescents; C-reactive protein; Cortisol; Depression; Heart rate; Physical activity