12. Low stress system activity and high peripheral inflammation in female competitive ballroom dancers

Abstract

Chronic stress has been linked with detrimental health effects. The present study aimed to investigate consequences of repeated strong stress system activation without habituation on stress system and inflammatory status in highly experienced competitive ballroom dancers. Ballroom dancing served as a model for repeated, non-habituating social-evaluative and physical stress. We recruited 20 highly experienced young ballroom dancers and 20 controls of both sexes. Participants collected five saliva samples throughout an ordinary day (no competitive activities) to assess cortisol (cort) and alpha-amylase (sAA) levels as markers of the activity of the hypothalamic–pituitary–adrenal (HPA) axis and the sympathetic nervous system, respectively. Further, participants provided a blood sample to determine basal interleukin- (IL-) 6 levels. ANOVAs revealed significant lower cort and sAA daily output in dancers compared to controls (cort: p = .007; sAA: p = .015) while there was no effect of sex or a group by sex interaction (all p > .400). Regarding IL-6, we found a significant group by sex interaction with highest levels in female dancers ( p = .021). Results show that dancers exhibit a dampened diurnal HPA axis and sympathetic activity while their inflammatory activity is enhanced. This indicates a reduced ability of stress systems to adequately control inflammatory activity which might be of pathological relevance. Future studies will show whether these alterations are predictive of negative health outcomes, even in young athletes.