when on active-duty, canadian armed forces (caf) members may be exposed to dangers and repetitive sub-concussive impacts such as explosive devices, loud gunfire, and handto-hand physical combat. these individuals are at constant risk of experiencing a variety of injuries including concussions. during a concussion, damage may occur to neural and vascular tissues that can cause physiological changes in the brain. abnormal breathing patterns may emerge, if there is damage to the brainstem or middle cerebral artery, which may reduce blood flow to the thalamus and brainstem and the respiratory control centres. therefore, the purpose of this study was to examine differences between healthy and concussed military members when completing a neurocognitive and physical task on measures of breathing function. two groups were recruited including a concussed and a healthy group. participants included males and females between the ages of 18-59 years who were active military members. healthy military members were required to have been absent of a concussion within the last 24 months. the concussed military members were required to have been diagnosed with at least 1 concussion by a medical professional within the previous 2-12 months. all participants had to have been absent of any debilitating injury or condition which would prevent them from safely engaging in physical activity or any other neurological disorder that have may altered their results and performance. although a concussion is classified as a neurological disorder, the participant must not have had any other neurological disorders. all participants were also required to be absent of any previous existing respiratory disorders. [...]