Cardiorespiratory fitness as protection against the development of memory intrusions: A prospective trauma analogue study.

Intrusive and distressing memories are at the core of post-traumatic stress disorder (PTSD). Since cardiorespiratory fitness (CRF) has been linked with improved mental health, emotion regulation, and memory function, CRF may, by promoting these capabilities, protect against the development of intrusions after trauma. We investigated the CRF-intrusion relationship and its potential mediators in 115 healthy individuals, using a trauma film to induce intrusions. As potential mediators, we assessed indices of pre-trauma mental health such as heart rate variability, subjective and psychobiological peri-traumatic responses, and memory. Critically, results showed that higher CRF was related to fewer intrusions, but no mediators emerged for the CRF-intrusion relationship. These results indicate that individuals displaying higher CRF are less prone to develop traumatic memory intrusions. Future studies may want to investigate whether promoting fitness prior to possible trauma exposure can boost resilience against the development of debilitating re-experiencing symptoms of PTSD.