exercise physiology exam 2

What is the difference between the Endocrine & nervous system?

• Endocrine: hormones released into blood to circulate to tissues ( slow systemic)

• Nervous: Neurotransmitter to relay message from one nerve to another ( fast localized)

What factors influence hormone concentration?

• Hormone secretion rate

• hormone metabolism/excretion (ex: lactate release of muscle which goes to brain or liver)

• Transport protein quantity

• Changes in plasma volume (as we sweat plasma decreases we can increase hormone activity)

In what ways does effect of hormones have on certain tissues?

• Concentration of hormone

• number of receptors on cell

• Affinity of receptors for hormones (ability to bind to receptors)

What is down regulation?

decrease number of receptors in response to high concentration hormone (resistant to hormone)

What is upregulation?

increase in number of receptors to concretion of hormones (becomes more sensitive)

What is a example of up & down regulation?

Type 2 diabetes before balance diet the cells would downregulation bc constant release hormone insulin. AFTER balance diet it would be upregulation bc receptors become more sensitive to insulin hormone.

How does hormone affect cellular/ tissue function?

1. Activation of genes to alter proteins synthesis

2. Activating second messengers in the cell via G protein

3. Altering membrane transport

How does steroid hormones activate genes to alter protein synthesis?

• can pass through membrane because they lipophilic

• gets a receptor to transport to nucleus

• binds to promoter region to make DNA to RNA

• binds to ribosome to make proteins

How does activation of second messenger hormone affect cellular function?

• hormone binds to receptor on cell membrane and via G protein

• G protein signals events inside the cell (removing or adding phosphate group)

• hormone never enters cell

How does membrane transport hormone affect cellular function?

• binds to cell’s surface

• causing changes inside of cell

• adds phosphates toe tell proteins to make glycogen while moving receptors to cell

What does the growth hormone do for the body?

• stimulate release of insulin-like growth factors (responsible for muscle growth)

• essential growth of all tissues (amino acid uptake and protein synthesis in our cells & long bone growth)

• Spares plasma glucose (opposes insulin action, reduces the use of plasma glucose, increase making of glucose, mobilizes fatty acids from adipose tissue)

• GH increase after exercise need to rebuild damage

What does growth hormone response to exercise?

• more GH produced will be in train individuals than untrained individuals

• as work rate increase so does GH bc more repair has to be done

• They longer we work the more GH we release

What does antidiuretic hormone do during exercise?

• reduce by water loss and reabsorbs water at Kidney tubules which is stimulated by high plasma osmolality ( salt con. of plasma) & low plasma volume

• ADH increases during exercise

What happens to T3 & T4 during exercise?

• increase metabolic rate

• primes the body to be more sensitive to other hormones

• responsible to oxygen drift during exercise

What happens to Calcitonin during exercise?

blocks Ca release from bone ( don’t wanna give up bone strength) and stimulates excretions by kidneys

What happens to parathyroid hormone?

when stimulates ca release from bone when Ca levels are low

Does epinephrine constriction or dilation?

Depends on the Adrenergic receptors

• ex: for A1 receptors it would vasoconstriction while in B2 receptors it would vasodilation

What happens to epinephrine & norepinephrine during exercise?

as you increase work rate and duration you release more epinephrine & norepinephrine

What happens to epinephrine as you train more?

• release less epinephrine & norepinephrine

• At maximal a trained athlete can release more epinephrine than untrained individual

is high cortisol good to have?

• yes during exercise but not long-term

• mobilizes tissues amino acids, mobilizes free fatty acids, stimulates making of glucose, and blocks entry into glucose into tissue

What happens to cortisol as we exercise?

• increase we exercise more

• goes away after exercise

Why do we about plasma glucose concentration?

helps protect the brain which uses it as its preferred source

What are four ways to protect plasma glucose concentration?

1. mobilize existing glucose from liver glycogen stores

2. mobilize FFA from adipose tissue

3. synthesize glucose from amino acids, glycerol, and lactate

4. block glucose entry into cells (anti-insulin effect)

What happens to muscle glycogen store during exercise?

as you increase intensity it decreases stores

• exercise will increase glycogen utilizes

What is epinephrine role in why glycogen is utilized in exercise?

epinephrine will tell muscle to use glycogen stores so it can used for work

if give medication blocker for epinephrine what would happen?

Ca+ drives glycogenesis which would come from muscle contractions which are independent from epinephrine

if we need to glucose utilization and cortisol decreases it what happens?

local controls in muscle would stop cortisol because we can still use glycogen driven from Ca & epinephrine

What are slow hormones for glucose regulation?

• T3 & T4

• Cortisol

• Growth hormone (decrease glucose uptake by tissue, increase FFA mobilization, increases gluconeogenesis)

What is the fasting hormone for glucose regulation?

• epinephrine & norepinephrine

• insulin

• glucagon

What happens to insulin during exercise?

Insulin would decrease

• untrained individuals would a lower insulin because epinephrine is going to release less

What happens to glucagon during exercise?

• glucagon will increase

• would be lower in trained individuals than untrained individuals

How does epinephrine regulate glucagon?

release of epinephrine would increase glucagon

How does epinephrine regulate insulin?

release of epinephrine would decrease insulin

If there’s less insulin how does muscle get glucose?

• body can take glucose faster during exercise

• more blood flow to deliver insulin & glucose to muscle

• greater gradient (more glucose outside than inside)

• muscle more sensitive to insulin

• ca from muscle contractions moves dormant glucose transporter to the membrane

What is are the purposes of the cirulatory system?

• Transport o2 & nutrients to tissues

• removes co2 & wastes from tissues

• regulates body temp

What does the pulmonary circuit do?

• it has deoxygenated blood which goes to the lungs

• pumps deoxygenated blood to lungs via pulmonary arteries

• returns oxygenated blood to left side of the heart via pulmonary veins

What does the systemic circuit do?

• left side of heart

• pumps oxygebated blood to whole body via arteries

• returns deoxygenated blood to right of heart via superior & inferior vena cava

What are the three layers of the heart?

• Endocardium (inner protective lining)

• myocardium (muscle contracts)

• epicardium/ pericardium (outer covering)

What do coronary arteries do for the heart?

provide oxygenated blood to heart tissues

What is a myocardial infarction?

cut of blood flow to the heart which causes necrosis

• trained individuals have a lower risk of heart attack than untrained individuals

What is heart ischemia?

decrease blood flow which causes hypoxia

whata re some features of cardiomyocytes?

• intercalated dics

• interdigtaing folds

• mechanical junctions (helps all cell contract together

• electrical junctions ( helps all cell contract together)

rely on aerobic respiration

What is the pathway that the heart contracts?

1. SA node (pacemaker of heart location in right atrium)

2. AV node (gateway to ventricles)

3. Bundle of His (forks into branches)

4. Purkinje fibers

What is sinus rhythm?

normal heartbeat triggered by the SA node

• heart is relax (diastole) most of the time

On a EKG what is the p-wave?

atria depolarizing (contracting)

On a EKG what is the QRS wave?

ventricle starts depolarizing until completeion

On a EKG what is the T wave?

ventricle in repolarization (relaxing)

If there volume increase what happens to the pressure?

pressure decreases

• liquid or air flows IN

• Gradient is always LOW TO HIGH

If there volume decrease what happens to the pressure?

pressure increases

• liquid or air flows OUT

What happens to ventricles during systole?

• volume decreases

• blood pressure increases

• pressures

• Blood pushes OUT

What happens to ventricles during systole?

• volume increase'

• blood pressure decreases

• pressure decreases

• Blood comes IN

What are the five steps of the cardiac cycle?

1. Atria and ventricle are in diastole

2. atria in systole

3. isovolumetric ventricle contraction (same volume of blood from atria)

4. ventricular systole

5. isovolumetric ventricle relaxation (during diastole)

What is MAP?

Mean arterial pressure

• Cardiac output x Total Vascular resistance

• diastole blood + .33 (systole blood pressure - diastole blood pressure)

What is cardiac output?

Heart is able to push out in a given time

How is MAP affect when heart is in failure?

MAP is low bc harder to drive blood to tissues

How is MAP affect during exercise?

higher bc the ratio is high between systole & diastole since heart is more in systole

What factors increase Blood pressure?

• increase HR

• increase Stroke volume

• increase blood volume

• increase blood viscosity

• increase peripheral resistance ( vasoconstriction)

How does the pumping cycle work in the left ventricle?

1. filling of the left ventricle (mitral valve is open, pressure is low)

2. mitral value closes (left ventricle begins contracting, pressure increases, this is end diastole volume)

3. Aortic value open due to increase pressure (equal to MAP)

4. pressure increase a little more but volume decreases

LOOK AT NOTES ON IPAD

How does the pumping cycle work in the left ventricle during exercise?

end systole will shift left because the increase of stroke volume

How does the pumping cycle work in the left ventricle after aerobic exercise?

• increase venous return (L.V. filling would be longer)

• increase stroke volume (space between E.S.V & E.D.V would be larger)

What are the components of the Fick equation?

• VO2= volume of O2 consumption

• Q = cardiac output (HR x Stroke volume)

• a= arterial O2 concentration

• V O2 = venous O2 concentration

What happens to the fick equation components during exercise?

• VO2= volume of O2 consumption (Increases)

• Q = cardiac output (HR x Stroke volume) (increases)

• a= arterial O2 concentration (same)

• V O2 = venous O2 concentration (decreases)

What happens to blood pressure during exercise?

• MAP increases

• systole increase

• diastole stays the same

What happens to stroke volume during exercise as untrained individual?

will increase until it will hit a plateau

• bc HR increase so L.V has less time to fill w/ blood

What happens to stroke volume during exercise as trained individual?

will increasing or plateau doesnt exist

• bc they have the ability to do more work

Why does does HR increase during exercise?

• parasympathetic nervous system withdrawals ACH

• sympathetic nervous system increase production of epinephrine and norepinephrine

What happens to