topic 9 - BCTT/BCBT Flashcards
what can affect cerebral circulation following concussion
concussion induced mechanical changes coupled with Nm cascade alterations
why might symptoms reappear / worsen with physical exertion
disturbed cerebral autoregualtion and CBF
what alterations are seen in NV coupling acutely following SRC
greater increase in PCAv (increased blood flow) and total activation
more nutrients are required to accomplish the same task
what may cause the abnormal regulation of CBF
altered autonomic NS function and/or altered CO2 regulation
CO2 tension in the blood = primary regulator of CBF
what is the effect on autonomic NS following concussion
altered ANS balance - reflected by higher HR during steady state exercise
primary ANS control centre (brainstem) may be damaged (rotational force to the upper cervical spine)
altered autonomic regulation believed to be due to changes in the autonomic centres in the brain and/or an uncoupling of the connections between the central ANS, the arterial baroreceptors, and the heart
what might be the mechanism of benefit of exercise on the brain
may not involve cerebrovascular disease risk due to rapid improvement
improved neuronal function / neuroplasticity likely
what type of exercise is cognitively protective
moderate aerobic exercise (60% of HR max performed 150 min/week)
associated with the greater levels of brain derived neurotrophic factor (BDNF) and improved CBF regulation
what is the role of BDNF
involved in neuron repair after injury, greater hippocampal volume, and improved spatial memory
what is the effect of physical deconditioning of the CV system due to prolonged rest
reduced CBF
what is the benefit of exercise training in those experiencing reduced CBF
restoration of autonomic balance/sensitisation of autregulatory system to gradual increase in BP with controlled exercise
beneficial for CBF control
what is the basis of exercise prescription in the BCTT
HR and BP at threshold of symptom exacerbation
what are contraindications of the BCTT
same contraindications of a cardiac stress test
beta blockers - changes vagal tone
history - unwilling, increased risk of CP disease, major depression
physical exam - neurologic/significant balance deficit
BMI - used but not accurate
what is included in the BCTT
very slow ramp incremental treadmill
1% incline per min until max 12% reached
speed increases after incline ~0.5 km/h every 1 min
each stage is 1 min
what is included in the BCBT
start at 60 bpm
resistance increased every 2 min (according to patient mass)
each stage is 2 min (takes twice as long)
- believed because it took longer to reach “physiological steady state” on a bike (NOT TRUE - no steady state after VT1)
when would a test be terminated
> 2 point symptom increase from baseline (no exercise in 7-10 range) or HR reached 90% of HR max (>180 bpm)
RPE > 18
voluntary exhaustion
