Hormonal Control During Exercise

1.What is the endocrine system’s job? 2.Do Male and female have different hormones?

1.What is the main difference between steroid and non-steroid hormones? How does this effect their function?

Use the pink highlighter, highlight pieces that you think are the main ideas or important points of the article. Using the blue highlighter, highlight words that you do not understand. If you understand it all then highlight the words that look like our vocab.

1.What specific hormone does your article cover? What is the hormone being used for or what is it causing? 2.Does it talk about any benefits or side effects of this hormone? If so what are they? 3.Do you agree with the article, do you find it distasteful, or give me your overall opinion of this article. 4.What would you like to know more about from this article? What did it leave you hanging on? 5.Write a decent summary, to share with the class, that explains what your article is about.

1.What are some of the different jobs that hormones have? 2.What is homeostasis? How do hormones help maintain this? ClipClip

1.Which hormone did you pick? Why? 2.What is the main function of your hormone and where is it secreted?

1.After watching this clip, give me your honest opinion on if you think this is ok or not. Why?

1.What are some effects or jobs the endocrine system takes on when you exercise?

1.Name the glands shown in the picture. A B D C E

On 7 you can just name the different glands

1.Estrogen 2.Calcitonin 3.Melatonin 4.Epinephrine 5.Renin 6.Insulin 7.Glucagon 8.Growth Hormone 9.Testosterone

The Endocrine System A communication system –Nervous system = electrical communication –Endocrine system = chemical communication Slower responding, longer lasting than nervous system Maintains homeostasis via hormones –Chemicals that control and regulate cell/organ activity –Act on target cells

The Endocrine System Coordinates integration of physiological systems during rest and exercise Maintains homeostasis during exercise –Controls substrate metabolism –Regulates fluid, electrolyte balance

Figure 4.1

Hormones: Steroid Hormones Lipid soluble, diffuse through membranes Secreted by four major glands –Adrenal cortex (cortisol, aldosterone) –Ovaries (estrogen, progesterone) –Testes (testosterone) –Placenta (estrogen, progesterone)

Hormones: Nonsteroid Hormones Not lipid soluble, cannot cross membranes Divided into two groups –Protein/peptide hormones Most nonsteroid hormones –Amino acid-derived hormones

Hormone Secretion Secreted in bursts –Plasma concentrations fluctuate over minutes/hours –Concentrations also fluctuate over days/weeks Secretion regulated by negative feedback –Hormone release causes change in body –High level of downstream change  secretion –Low level of downstream change  secretion –Example: home thermostat

Hormone Activity Plasma concentration can be poor indicator of hormone activity –Cells change sensitivity to hormones –Number of receptors on cell surface can change Downregulation:  number of receptors during high plasma concentration = desensitization Upregulation:  number of receptors during high plasma concentration = sensitization

Hormone Receptors Hormones limit scope of their effects by using hormone-specific receptors No receptor on cell surface = no hormone effect –Hormone only affects tissues with specific receptor –Hormone exerts effects after binding with receptor –Typical cell has 2,000 to 10,000 receptors Hormone binds to receptor: hormone– receptor complex

Steroid Hormone Actions Lipid soluble (can cross cell membranes) Steroid hormone receptors found inside cell, in cytoplasm or nucleus Hormone–receptor complex enters nucleus –Binds to DNA, direct gene activation

Figure 4.2

Nonsteroid Hormone Actions Not lipid soluble (cannot cross cell membrane) Receptors on cell membrane  second messengers –Carry out hormone effects –Intensify strength of hormone signal Common second messengers –Cyclic adenosine monophosphate (cAMP)

Figure 4.3

1.What are some chemical processes taking place during exercise. What happens in your body during exercise?

Hormonal Regulation of Metabolism During Exercise Major endocrine glands responsible for metabolic regulation –Anterior pituitary gland –Thyroid gland –Adrenal gland –Pancreas Hormones released by these glands affect metabolism of carbohydrate and fat during exercise

Endocrine Regulation of Metabolism: Anterior Pituitary Gland Pituitary gland attached to hypothalamus Tow main lobes: anterior and posterior Secretes hormones in response to hypothalamic hormones –Exercise  secretion of all anterior pituitary hormones

Endocrine Regulation of Metabolism: Anterior Pituitary Gland Releases growth hormone (GH) –Builds tissues, organs –Promotes muscle growth (hypertrophy) –Stimulates fat metabolism GH release proportional to exercise intensity

Endocrine Regulation of Metabolism: Pancreas Insulin: lowers blood glucose –Counters hyperglycemia, opposes glucagon –  Glucose transport into cells –  Synthesis of glycogen, protein, fat – Inhibits gluconeogenesis Glucagon: raises blood glucose –Counters hypoglycemia, opposes insulin –  Glycogenolysis, gluconeogenesis

Regulation of Carbohydrate Metabolism During Exercise Glucose must be available to tissues Glycogenolysis (glycogen  glucose) Gluconeogenesis (FFAs, protein  glucose)

Regulation of Carbohydrate Metabolism During Exercise Adequate glucose during exercise requires –Glucose release by liver –Glucose uptake by muscles Hormones that  circulating glucose –Glucagon –Epinephrine Amount of glucose released from liver depends on exercise intensity; duration

Regulation of Carbohydrate Metabolism During Exercise As exercise intensity increases –Muscle glycogen used before liver glycogen As exercise duration increases –More liver glycogen utilized

Regulation of Fat Metabolism During Exercise FFA mobilization and fat metabolism critical to endurance exercise performance –Glycogen depleted, need fat substrates –In response, hormones accelerate fat breakdown (lipolysis) Triglycerides  FFAs + glycerol –Fat stored as triglycerides in adipose tissue –Broken down into FFAs, transported to muscle

Hormonal Regulation of Fluid and Electrolytes During Exercise During exercise, plasma volume , causing –  Plasma water content via sweating –  Heart strain,  blood pressure Hormones correct fluid imbalances

Hormonal Regulation of Fluid and Electrolytes: Posterior Pituitary Posterior pituitary –Secretes antidiuretic hormone (ADH) ADH involved with exercise –  Water reabsorption at kidneys –Less water in urine

Hormonal Regulation of Fluid and Electrolytes: Posterior Pituitary Stimuli for ADH release –  Plasma volume = hemoconcentration ADH released, increasing water retention by kidneys Minimizes water loss, severe dehydration

Figure 4.6

Hormonal Regulation of Fluid and Electrolytes: Adrenal Cortex Adrenal cortex –Secretes aldosterone Aldosterone effects –  Na + retention by kidneys –  Na + retention   water retention via osmosis –  Na + retention   K + excretion

Hormonal Regulation of Fluid and Electrolytes: Adrenal Cortex Stimuli for aldosterone release –  Plasma Na + –  Blood volume, blood pressure –  Plasma K +

Figure 4.8

Hormonal Regulation of Fluid and Electrolytes: Osmolality Osmolality –Measure of concentration of dissolved particles (proteins, ions, etc.) in body fluid compartments –Normal value: ~300 mOsm/kg Osmolality and osmosis –If compartment osmolality , water drawn in –If compartment osmolality , water drawn out

Hormonal Regulation of Fluid and Electrolytes: Osmolality Aldosterone and osmosis –Na + retention   osmolality –  Osmolality   water retention –Where Na + moves, water follows Osmotic water movement minimizes loss of plasma volume, maintains blood pressure

Hormonal Regulation of Fluid and Electrolytes: Osmolality ADH, aldosterone effects persist for 12 to 48 h after exercise Prolonged Na + retention  abnormally high [Na + ] after exercise –Water follows Na + –Prolonged rehydration effects

1.Estrogen 2.Calcitonin 3.Melatonin 4.Epinephrine 5.Renin 6.Insulin 7.Glucagon 8.Growth Hormone 9.Testosterone

1.How are aldosterone and ADH similar? How are they different? 2.What is the main job of Insulin?