Endocrine Response to Exercise Flashcards
Major Endocrine Organs
Pituitary, thyroid, parathyroid, adrenal, pineal, and thymus glands
Secondary organs containing areas of endocrine tissue
Pancreas, gonads, hypothalamus, adipose tissue
Types of hormones
Steroid-derived hormones
Amine and polypeptide hormones
Factors determining plasma hormone levels
Quantity synthesized in the host gland
Rate of either catabolism or secretion into the blood
Quantity of transport proteins present
Plasma volumes
Hormonal gland stimulation
ACTH released into blood; adrenal cortex secretes glucocorticoids; glucocorticoids influence several target organs
Humoral gland stimulation
Capillary blood contains high glucose Insulin secreted by pancreas Target cells absorb more glucose from blood Capillary blood drops glucose levels Low blood sugar inhibits insulin
Neural gland stimation
Preganglionic sympathetic nerve stimulates adrenal medulla; adrenal medulla secretes catecholamines into blood
Ant. Pituitary gland hormones
GH, ACTH, FSH, LH, Testosterone
Post. Pituitary hormones
ADH
Adrenal gland hormones
Cortisol, epinephrine, norepinephrine
Pancreas hormones
Insulin, glucagon
Growth hormone
Promotes cell division and proliferation
Slows carb breakdown, burns fats
Physical activity extends its action
Antidiuretic Hormone
Increases contraction of smooth muscle and reabsorption of water by kidneys
Physical activity stimulates release
Adrenal Cortex hormones
Glucocorticoids
Adrenal Medulla hormones
Epinephrine; Norepinephrine
Epinephrine
Increase Q, increase blood sugar and glycogen breakdown
Remains unchanged below 60% VO2 max
Norephinephrine
Constricts blood vessels; increased in activities exceeding 50% VO2 max
Insulin
Stores glyogen and promotes glucose entry in cells, also involved with protein synthesis
Glucagon
Increases blood glucose levels
Endurance training affect on endocrine system
Magnitude of hormonal response decreases due to increased efficiency
Maximal exercise training affect on endocrine system
Identical or higher hormonal response than untrained subjet
Hormonal factors in muscle size and function
- Changes in hepatic and extrahepatic hormone clearance rates
- Differential rates of hormone secretion
- Altered receptor site activation via neurohormonal control
Short term Immune response to training
Moderate exercise: Boosts for several hours
Exhaustive exercise: Depresses immune system
Long term Immune response to training
Aerobic training positively affects natural immune functions
Enhanced function of cytotoxic immune response
Diminished age related decrease in T-cell function and associated cytokine production
