Lecture 21 and 22 Flashcards
Hormones
many hormones impact multiple tissue types and ….
have diverse effects
some hormones are both …. and ….
both catabolic and anabolic
what type of hormones tend to act faster
peptide and amine hormones
what type of hormones tend to act slower
steroid
in the big picture, prolonged or sustained competitive exercise will have what impact hormones
increase several catabolic hormones and suppress insulin
in the big picture, activating many motor units tends to cause what for hormones
cause more anabolic hormone profile, in exercise and recovery
are steroid hormones water soluble or insoluble
water insoluble
are peptide and amine hormones water soluble or insoluble
water soluble
when are peptide and amine hormones made
made in advance
how do steroid hormones work
steroid hormones enter cells and bind at the nucleus
how do peptide hormones work
attach at the cell surface
use second messengers
what are second messengers
intracellular compound that increases in concentration with binding of a hormone to its receptor and smplifies the cellular response
hormones change the rates of specific reactions in target cells by changing the rates of :
- transport across membrane e.g insulin
- secretory activity e.g GHRH
- enzyme activity e.g HSL
- protein synthesis e.g testosterone
how does hormone concentration in blood affect the rate of secretion
if there is more in the circulation, this will remove the stimulus to secrete it
hormone concentration in the blood can affect the rate of inactivation or
excretion
hormone concentration in the blood can effect the quantity of what
quantity of transport protein (for steroids)
what affects hormone receptor interactions
- blood hormone levels
- number of target cell receptors
- affinity of binding
at rest you have a larger …. volume and you are secreting more what into the circulation
at rest you have a larger plasma volume and are secreting more insulin into the circulation
in exercise there is a change in what factors that can change the cells sensitivity to hormone
- change in secretion
- change in plasma volume
- change metabolism / clearance
- change in receptor sensitivity
- change in receptor density
during rest how is the release of insulin controlled and why is this changed during exercise
by negative feedback, changed in exercise as exercise is a stressor
during exercise there is greater activation of what nervous systems
SNS and PNS
during exercise what nervous stimulation is increased on the medulla
SNS stimulation
what glands are associated with catabolic or stress situations (exercsise)
adrenal glands = stress hormones
what glands are associated with anabolic states (recovery)
gonads = sex hormones
what is the speed of the catecholamine response to exercise
vital , FAST response
what are the effects of the catecholamine response to exercise
- CV pressor responses
- increased substrate mobilsation
- facilitates other catabolic hormones
- immune mobilisation
which catecholamine increases the most during the progression towards VO2 max
noradrenaline, also small increase in adrenaline
what is the cardiovascular effect of catecholamines
increased blood pressure and redistribution
what happens to the catecholamine response at a given absolute intensity after training for awhile
decreased catecholamine response at given absolute intensity
what happens to the catecholamine response at a given relative intensity after training for awhile
same response
after training for awhile what will happen to the amount of growth hormone released and why
you have an adaptation to exercise, better cardiovascular capacity, less stress and can access fuels easier
so growth hormone isn’t released as much after training
in what way does adrenaline increase with exercise intensity
increases disproportionally with exercise intensity
adrenaline and free calcium will increase what in the muscle
increase glycogenolysis in muscle
what has a massive effect on glycogen depletion
exercise intensity
mobilisation of free fatty acids spares what at moderate exercise intensities
spares glycogen
mobilisation of free fatty acids is strong in what exercise
moderate or prolonged
when is there less free fatty acid mobilisation during exercise
with increased CHO feeding
why is there a decrease in fatty acid mobilisation in heavy exercise despite strong hormonal drive for free fatty acid mobilisation
- decreased blood flow to adipose tissue
- increased acidity (promotes resynthesis of triglycerides, and inhibits HSL)
during heavy or prolonged exercise where energy is decreased what effect will cortisol released from the adrenal cortex have
- increased free fatty acids (lipolysis)
- increased amino acids (used for gluconeogenesis)
- decreased glucose uptake
two ways that cortisol is controlled during exercise
negative feedback control
feedforward control
insulin is anabolic and suppressed by what
suppressed by catecholamines
glucose uptake by muscle is what times faster in exercise
7-20x faster
insulin decreases during exercise, but why is glucose uptake increased during exercise
increased GLUT4 activity and increased insulin sensitivity
higher intensity exercise has more powerful effects on hormones but what is this response blunted by
aerobic fitness (relative intensity of exercise)
CHO availability ( before and during exercise)
fitness allows for much reduced hormone responses to what
to same absolute exercise intensity
