Flashcards in Exercise Deck (51)
Why are the categories of physical activities we are engaged in?
everyday activity, especially manual jobs
What is VO2 max?
The maximal oxygen consumption measured during incremental exercise
What is VO2 max a good indicator of?
physical aerobic capacity
How much oxygen is dissipate with heat?
80%, only 20% goes into doing the exercise
Which major artery is the first to get constricted upon intense exercise
What are the vasodilators involved in heat dissipation
metabolic vasodilators from contracting muscles
NO from endothelium
ATP from unsaturated hemoglobin
Why is postural hypertension common post-exercise?
because the MAP is sharply decreased due to muscular vasodilation. BP cannot keep up
How do we avoid postural hypertension after exercise
raise the legs and hydrate
Why do athletes have a slower heart rate?
Because the stroke volume is higher
T/F the period of systole gets extended in an athlete
False, the diastole increases and slows down the HR
Why do athletes use EPO?
although exercise increases blood volume, it also dilutes RBC. EPO can increase RBC amount and increase O2 carrying capacity and CO
T/F Trained muscles have increased capillary recruitment
True, hence the total delivery of oxygen is enhanced
T/F Oxygen saturation is usually not as efficient at the lung when exercising
False, although pulmonary blood flow is faster, the max saturation can still be achieved in most people
T/F O2 plays a role in ventilation control
How does heat impair exercise capacity
electrolyte imbalance due to excess sweat
blood diverted to skin rather than muscles
How is type I fibre different to type II fibre
type I - higher endurance, higher oxygen capacity
type II - higher force and power output, fatigue prone
T/F You can't change the amount of type II fibres you have
False, it's just extremely difficult, but it's much easier the other way around
Why is the initial increase in muscle strength so quick with resistance exercise
You are increasing the amount of nerve innervation and motor unit recruitment
What are the mitochondrial adaptation with exercise?
increased mitochondrial density and oxidative enzymes
reduced CHO use and lactate production
increased fat oxidation
improved insulin action
Which glucose channel is upregulated on muscles with exercise?
What happens when athletes "hit the wall"
run out of carbohydrate and only rely on fat
Which fuel do we use during sprints
Which fuel do we use in endurance exercise?
aerobic metabolism of fat or carbohydrate
At what intensity is fat oxidation most efficient
~50% max intensity (VO2 Max)
Why do we use more carbohydrate when we grow older?
because the exercise we do is relatively higher in intensity
What is fatigue
inability to maintain the required or expected force or power output
When is fatigue pathological
when it manifests at rest
What are the feedback signals from the muscles to CNS
running out of ATP
build up of H+ and RoS
What do we look for on the ECG when putting a cardiac patient on the treadmill for exercise diagnosis