RecruitingBehavioural interventionTreatment Optimization of Brain-injured WarfightersPrescribed sub-symptomatic adaptable exercise treatment (SAET) is a potential solution that promotes recovery needs following a TBI. SAET has been shown to benefit the mind and body in ways that decrease the severity and frequency of mild TBI (mTBI) symptoms. This study aims to validate SAET as an alternative, adaptable treatment or SMs with mTBI that focuses on reducing symptoms, improving mental health, increasing physiological functioning, and ultimately returning to duty. The objective of this study is to develop a prescribed exercise treatment program for warfighters with mTBI that can be personalized for SM's needs (i.e., medical and occupational) and is adaptable to various clinical resources (e.g., forward operating bases, rural clinics, and mTBI specialty programs). The key question raised by this study is whether SAET is more effective than a stretching control group (SCG) in reducing neurobehavioral symptoms among SMs with persistent complaints following a mTBI.