LECTURE 3: respiratory system, GI tract during exercise Flashcards
what is the purpose of respiratory muscle training (RMT)?
training of the respiratory muscles to increase respiratory muscle endurance (RME)
provide an example of a breath trainer
altitude masks: limit air that can be breathed in, making respiratory muscles work harder
what is spirometry a measure of?
pulmonary volumes and rate of expired airflow
list two spirometry tests
Forced vital capacity (FVC), Forced expiratory capacity in one second (FEV1)
describe what an FVC test measures
vital capacity, amount of air that can be forcefully exhaled after a maximal inhale
describe what an FEV1 test measures
amount of air that can be forcefully exhaled in one second after a maximal inhale
what is a normal FEV1/VC ratio?
> /= 80%
at what altitude does altitude have noticeable effects on performance?
~1500m
does altitude affect anaerobic or aerobic performance more?
aerobic: lower PO2 leads to lower O2 delivery to muscle. not anaerobic due to the low need for O2 during exercise
is VO2max higher or lower at altitude?
Lower - due to lower oxygen extraction
what factors influence the speed of adaptation to training at altitude?
previous exposure to altitude, individual variability
if oxygen saturation at sea level is close to 98/99%, what is the saturation at altitude?
85/86%
list five influences on Hb concentration
training, nutrition, altitude, gender, genetics
list two things determining shifts in the oxyhemoglobin dissociation curve
PO2 of blood, affinity of Hb for O2
is myoglobin’s affinity for O2 higher or lower than haemoglobin?
higher
does high temperature lower or raise Hb-O2 affinity and which direction does it shift the oxyhemoglobin dissociation curve?
lowers, right shift
does high pH lower or raise Hb-O2 affinity and which direction does it shift the oxyhemoglobin dissociation curve?
raises, left shift
is it more beneficial to have high or low pH at the tissue level of ciruclation?
low pH at the tissue level, this encourages Hb-O2 dissociation for O2 transport into tissue
what form is 70% of CO2 transported in in the blood
bicarbonate ions (HCO3-)
what percentage of CO2 is transported bound to Hb?
20%
does ventilation fall or rise during prolonged submax exercise in hot/humid conditions when compared to non-hot/humid?
rise
how does training reduce the ventilatory response to exercise?
changes in aerobic capacity of muscles result in lower H+ production and less afferent feedback from muscles to stimulate breathing
does the training reduction in ventilatory response to exercise involve changes to lung structure?
no
why do GI tract difficulties mostly effect endurance athletes?
greater time exercising allows for more time for the gut to play up
what percentage of endurance athletes experience GI discomfort?
> 60%
What chemical passes through the epithelial lining of the gut when exercising in the heat that shouldn’t
LPS/endotoxin
what happens to the gut epithelia to allow LPS/endotoxin to pass into the bloodstream?
permeability increases, tight junctions between cells loosen
what happens to the gut epithelia to allow LPS/endotoxin to pass into the bloodstream?
permeability increases, tight junctions between cells loosen
list three factors increasing GI disturbances in exercise
weight bearing vs non-weight bearing exercise, high intensity exercise vs low intensity, environmental conditions such as heat
