In a previous study, we developed and evaluated a pilot predeployment stress inoculation training (SIT) program designed to teach relaxation breathing skills to minimize negative mental health consequences of combat stress. This study extends the investigation of the effectiveness of a SIT program of relaxation breathing on perceived stress symptoms and other mental health outcomes in a longitudinal randomized controlled trial. Heart rate variability was used to test the effect of SIT in reducing autonomic arousal in response to simulated combat-related stressors. Soldiers were randomized into SIT versus control groups at baseline and followed for 1 to 2 years. SIT did not have an overall effect on perceived stress scores or posttraumatic stress disorder symptoms when controlling for covariates. Consistent with previous findings in which SIT mitigated the risk of posttraumatic stress disorder in those without baseline mental health problems, the current study showed that SIT may prevent hyperarousal symptoms, among mentally healthy military personnel who are not otherwise interested in learning stress-control techniques, but was not supported as a general predeployment mental health prevention strategy. A heart rate variability increase in response to relaxation breathing training suggests further research is warranted into mental health effects of self-regulation techniques. (PsycINFO Database Record (c) 2018 APA, all rights reserved)
