The influence of concussion on cardio-autonomic function during cognition before and after exercise

Abstract

In an average day of a student-athlete, they must endure the cognitive demand of classes, physical stress of practice, and then end the day studying and doing homework for the next day. Cardio-autonomic regulation is an integral process linking the neurologic and cardiological systems, that responds and adapts to these changing environmental stressors to maintain overall effective functioning. The adaptation of the cardio-autonomic system to environmental stressors is often impaired in people who have experienced a concussion. The aim of the current study, was to assess cardio-autonomic function in a group of athletes with and without a history of sports-related concussion (SRC) in an experimental paradigm designed to mimic an average day of a studentathlete. Heart-rate variability (HRV) was assessed in a group of adolescent athletes with a history of diagnosed concussion (n = 16) and healthy matched controls (n = 19) (1) at rest (2) during a switch task paradigm and (3) during a switch task paradigm following a 20-minute bout of aerobic exercise at ~70% of their theoretical max heart rate. Results of the preliminary investigation revealed that individuals with a history of SRC exhibited alterations in HRV at rest, that were exacerbated by the cognitive load of the switch task. However, following the bout of aerobic exercise, HRV normalized in the individuals with a history of SRC. These results continue to demonstrate cardio-autonomic dysregulation following a SRC. It also indicates the potential therapeutic benefit of aerobic exercise in mediating these cardio-autonomic abnormalities.