title: Resting vagal control and resilience as predictors of cardiovascular allostasis in peacekeepers.
abstract: The body's adaptive reaction to a stressful event, an allostatic response, involves vigorous physiological engagement with and efficient recovery from stress. Our aim was to investigate the influence of individual predispositions on cardiac responses to and recovery from a standardized psychosocial stress task (Trier Social Stress Task) in peacekeepers. We hypothesized that those individuals with higher trait resilience and those with higher resting vagal control would be more likely to present an allostatic response: a vigorous cardiac response to stress (i.e., reduction in interbeat intervals and heart rate variability (HRV)) coupled with a significant cardiac recovery in the aftermath. Fifty male military personnel with a mean age of 25.4 years (SD ± 5.99) were evaluated after returning from a peacekeeping mission. Electrocardiogram recordings were made throughout the experimental session, which consisted five conditions: basal, speech preparation, speech delivery, arithmetic task, and recovery. Mean interbeat intervals and HRV were calculated for each condition. An Ego-Resilience Scale and resting vagal control assessed individual predispositions. Stress tasks reduced interbeat intervals (tachycardia) and HRV in comparison with basal, with return to basal in the aftermath (p < 0.001, for all comparisons). Resilience and resting vagal control correlated positively with cardiac parameters for both stress reactivity and recovery (r ≥ 0.29; p < 0.05). In conclusion, peacekeepers showing higher trait resilience and those with higher resting vagal control presented a more adaptive allostatic reaction characterized by vigorous cardiac response to stress (i.e., tachycardia and vagal withdrawal) and efficient cardiac recovery after stress cessation.
authors: Departamento de Ciências Biológicas, Universidade Federal de Ouro Preto, Ouro Preto, MG, Brazil. souzaggl@gmail.com
authors: Gabriela Guerra Leal
authors: GG
authors: Souza
authors: Ludmila Naves
authors: LN
authors: Magalhães
authors: Thiago Amorim Ribeiro Da
authors: TA
authors: Cruz
authors: Ana Carolina Ferraz
authors: AC
authors: Mendonça-De-Souza
authors: Antônio Fernando A
authors: AF
authors: Duarte
authors: Nastassja L
authors: NL
authors: Fischer
authors: Wanderson F
authors: WF
authors: Souza
authors: Evandro Da Silva F
authors: Eda S
authors: Coutinho
authors: Jaime
authors: J
authors: Vila
authors: Sonia
authors: S
authors: Gleiser
authors: Ivan
authors: I
authors: Figueira
authors: Eliane
authors: E
authors: Volchan
mesh_terms: D000328:Adult; D052636:Allostasis / Q000502:physiology*; D001938:Brazil / Q000208:ethnology; D002320:Cardiovascular Physiological Phenomena; D006205:Haiti; D006339:Heart Rate / Q000502:physiology; D006801:Humans; D008297:Male; D008889:Military Personnel / Q000523:psychology*; D055500:Resilience, Psychological; D013315:Stress, Psychological / Q000503:physiopathology*; D014630:Vagus Nerve / Q000502:physiology