Chapter 5: Hormonal Responses to Exercise Flashcards
GH location of synthesis
anterior pituitary
stimulus for GH release
*exercise, sleep, stress, low BG
actions of GH
anabolic hormone, promotes muscle hypertrophy
how does GH change for prolonged exercise? graded exercise?
increased duration increases GH, increased intensity increases GH
catecholamines site of synthesis
adrenal medulla
stimulus for catecholamine release
flight or fight response
how does catecholamine levels change for prolonged exercise? graded exercise?
increased duration increases NE & Epi, increased intensity increases NE & Epi
how do levels of NE and Epi change with training?
NE & Epi decrease at the same given work rate with training
cortisol location of synthesis
adrenal cortex
stimulus for cortisol release
*exercise, stress, bone breaks
how do cortisol levels change with exercise?
increased intensity increases cortisol levels
glucagon site of synthesis
pancreas
stimulus for glucagon release
decreased BG
how do blood glucagon levels differ for trained and untrained athletes during prolonged exercise?
untrained individuals see a larger percent increase in glucagon levels (using more glycogen) whereas trained individuals do not see a percent increase in glucagon levels over time at the same intensity
insulin site of synthesis
pancreas
stimulus for insulin release
increased BG
how do NE and Epi affect the hormones secreted by the pancreas?
stimulate glucagon secretion and inhibit insulin secretion
how do insulin levels change with prolonged exercise? graded exercise?
increased duration decreases insulin, increased intensity decrease insulin
which hormones increase circulating BG
glucagon, GH, cortisol, NE/Epi
adequate glucose during exercise requires:
1) glucose release by the liver
2) glucose uptake by muscles
actions of catecholamines
1) increase glycogenolysis at the liver & muscle (muscle glycogen used first) via B1 ADR
3) stimulates glucagon release and inhibits insulin release
2) increase lipolysis in adipose tissue
actions of glucagon
1) increases glycogenolysis and gluconeogenesis at the liver
2) lipolysis in adipose tissue
actions of GH
1) gluconeogenesis in liver
2) lipolysis in adipose tissue
actions of cortisol
1) gluconeogenesis in the liver
2) lipolysis in adipose tissue