Exam 2 Flashcards
neuroendocrine system
endocrine system releases hormones into blood to circulate to tissues
the nervous system uses neurotransmitters to relay messages from one nerve to another
types of hormones
amino acid derivatives
peptide/protein
steroids
Insulin
fast acting hormone
uptake and storage of glucose and FFA
insulin during exercise
insulin in plasma concentration decreases during exercise
decreased insulin response following exercise
glucagon
fast acting hormone
mobilization of glucose and FFA fuels
glucagon during exercise
glucagon in plasma concentration increases during exercise
decreased response following training
insulin and glucagon secretion influenced by…
…catecholamines
absorption of a meal (what happens with insulin and glucagon)
increased insulin, decreased glucagon
increased storage of glycogen, fat and protein
decreased plasma glucose, amino acids, and fatty acids
during fasting and exercise (what happens with insulin and glucagon)
decreased insulin, increased glucagon
increased hydrolysis of glycogen, fat, and protein
increased gluconeogenesis
increased plasma glucose, amino acids, and fatty acids
trained vs untrained glucagon concentration
as one gets trained, glucagon concentration no longer increases during exercise because NE and E can mobilize faster
only untrained individuals rely on glucagon and insulin (on top of NE and E)
hormone-substrate interaction
- FFA mobilization dependent on hormone-sensitive lipase (HSL)
- FFA mobilization decreases during heavy exercise
- due to high levels of lactic acid (promotes resynthesis of triglycerides) the more lactic acid in the system the more FFA reduces
- elevated H+ concentration inhibits HSL
- inadequate blood flow to adipose tissue
- insufficient albumin to transport FFA in plasma
2 adjustments of blood flow during exercise
- increased cardiac output
- redistribution of blood flow of inactive organs to active muscle
pulmonary circuit
- right side of heart
- deox blood to lungs via pulmonary arteries
- ox blood to left side of heart via pulmonary veins
systemic circuit
- left side of the heart
- ox blood to body via arteries
- deox blood to right side of heart via veins
pericardium
- rigid sac around heart that keeps it in place and limits expansion
- athletes have expanded pericardium
cardiac muscle vs skeletal muscle (nuclei, energy system, structure)
- cardiac single nucleus in each fiber, skeletal multiple nuclei
- cardiac primarily aerobic, skeletal aerobic and anaerobic
- both striated but cardiac shorter, skeletal longer
Exercise training and the heart
regular exercise reduces incidence of heart attack and improves survival from heart attacks due to accumulation of oxidative stress from exercise developing antioxidant capacity in heart
Systole
- contraction phase
- ejection of blood
Diastole
- relaxation phase
- filling with blood
diastole and systole at rest and exercise
at rest diastole is longer than systole
during exercise both shorten, diastole decreases time a lot more
Pressure changes in diastole
- pressure in ventricles is low, filing with blood from atria
pressure changes in systole
- pressure in ventricles rises, blood ejected in pulmonary and systemic circulation
heart sounds
- first: closing of AV valves
- second: closing of aortic and pulmonary valves
blood pressure expressed as
systolic/ diastolic
120/80
- beginning of Koroskoff sound is systolic, sound disappearing is diastolic