Key result
Acute concussion was associated with a significantly lower heart rate at exercise onset and greater perceived exertion compared to the recovered state.
Why the study?
Does acute concussion alter heart rate and perceived exertion during graded treadmill exercise compared to post-recovery and healthy controls?
Observational
Does acute concussion alter heart rate and perceived exertion during graded treadmill exercise compared to post-recovery and healthy controls?
Acute concussion impairs the autonomic transition from parasympathetic to sympathetic control at the onset of exercise, resulting in lower initial heart rate and higher perceived exertion.
May warrant modified exercise protocols after acute concussion; leaves open prospective validation of monitoring utility.
OBJECTIVE: Research suggests that one physiological effect of concussion is a disruption in regulation of autonomic nervous system control that affects the balance between parasympathetic and sympathetic output. While changes in heart rate after concussion have been observed, the nature of the heart rate change during progressive exercise has not been well evaluated in acutely symptomatic patients. Additionally, little is known about the relationship between HR and RPE in this population. METHODS: We compared changes in heart rate and perceived effort during graded treadmill exertion in recently concussed patients to elucidate the effect of brain injury on cardiovascular response to exercise. Resting HR, HR on exercise initiation, and changes in HR and RPE during the Buffalo Concussion Treadmill Test (BCTT) were compared on two test visits: When patients were symptomatic (acute) and after recovery. Results were compared with the test-retest results obtained from a control group consisting of healthy, non-concussed individuals. RESULTS: Patients had a significantly lower HR at onset of exercise when acutely concussed as compared to when recovered and reported greater perceived exertion at every exercise intensity level when symptomatic, despite exercising at lower workloads, than when recovered. Sympathetic response to increased exertion was not affected by concussion - HR increased in response to exercise at a comparable rate in both tests. These differences observed in response to exercise between the first BCTT and follow-up evaluation in initially concussed patients were not present in non-concussed individuals. CONCLUSION: Our results suggest that during the acute phase after concussion, acutely concussed patients demonstrated an impaired ability to shift from parasympathetic to sympathetic control over heart rate at the onset of exercise. Changes in the autonomic nervous system after concussion may be more complex than previously reported. Continued evaluation of autonomic regulatory effects in the acute phase after concussion is warranted.
No takes yet. Share an insight, caveat, or question.
Hinds et al. (2016) conducted an observational in Concussion. Acute concussion vs. Recovered state and healthy non-concussed controls was evaluated on Changes in heart rate and perceived effort during graded treadmill exertion. Acute concussion was associated with a significantly lower heart rate at exercise onset and greater perceived exertion compared to the recovered state.
Synapse has enriched 5 closely related papers on similar clinical questions. Consider them for comparative context: