Hormonal Regulation and Response to Exercise

Vocabulary flashcards covering key hormones, organs, mechanisms, and exercise responses from Chapter 5: Hormonal Regulation and Response to Exercise.

Hormonal Regulation

The process by which hormones adjust energy supply to meet the metabolic demands of exercise.

Fast-acting Hormones

Hormones that change rapidly to match abrupt shifts in exercise intensity or duration.

ex. epinephrine, norepinephrine, insulin, glucagon

Permissive Hormones

Hormones that support or enhance the actions of fast-acting hormones during exercise

ex. cortisol, growth hormone

Catecholamines

Collective term for epinephrine and norepinephrine, released from the adrenal medulla to mobilize glucose and free fatty acids.

Epinephrine (E)

A catecholamine that rises with exercise intensity and duration, stimulating glycogen breakdown, glucose output, and lipolysis.

Norepinephrine (NE)

Catecholamine similar to epinephrine; increases with exercise, promoting fuel mobilization and cardiovascular responses.

Insulin

Pancreatic hormone that promotes glucose uptake and storage; its plasma level falls during exercise to reduce glucose storage.

Glucagon

Pancreatic hormone that stimulates hepatic glucose release and fat mobilization; rises during exercise.

Cortisol

Adrenal cortex hormone that maintains blood glucose via gluconeogenesis, protein breakdown, and fat mobilization; increases during prolonged or intense exercise.

Growth Hormone (GH)

Anterior pituitary hormone that increases with long or intense exercise, stimulating lipolysis, glucose sparing, and tissue repair.

Adrenal Medulla

Inner region of adrenal gland secreting epinephrine and norepinephrine during exercise.

Adrenal Cortex

Outer region of adrenal gland that releases cortisol to support gluconeogenesis and fat breakdown.

Pancreas (Endocrine Function)

Gland that secretes insulin and glucagon to regulate blood glucose and fuel storage or release.

Anterior Pituitary

Pituitary lobe that releases growth hormone in response to exercise, sleep, stress, or low blood glucose; it mobilizes fat and supports tissue growth

Gluconeogenesis

Formation of glucose from non-carbohydrate sources enhanced by cortisol and prolonged exercise.

ex. amino acids, glycerol, lactate

Glycogenolysis

Breakdown of liver or muscle glycogen to glucose in the liver, stimulated by epinephrine and norepinephrine.

Lipolysis

Hydrolysis of triglycerides into free fatty acids and glycerol; promoted by catecholamines, GH, and glucagon.

Hormone-Sensitive Lipase (HSL)

enzyme responsible to releasing FFAs from adipose tissue so they can be used as a fuel source its activity is inhibited by high lactate levels during intense exercise.

Free Fatty Acids (FFA)

Fatty acids released into blood during lipolysis; used for energy, especially when glucose is spared.

Training effects on catecholamine

Endurance training lowers plasma epinephrine and norepinephrine responses at the same absolute workload.

Blood Glucose Maintenance Mechanisms

liver glycogen breakdown

gluconeogenesis

fat mobilization

blocking glucose entry into cells.

Fuel Sparing

Hormonal strategy (via GH, cortisol, catecholamines) that shifts reliance from glucose to fat during exercise.

Albumin Saturation

Limitation in blood FFA transport when albumin binding sites become filled during intense exercise.

Fat Mobilization Limitation

Reduced FFA availability during heavy exercise due to lactate inhibition of HSL, decreased adipose blood flow, and albumin saturation.

Sympathetic Nervous System Regulation

Neural input that modulates insulin (↓) and glucagon (↑) secretion during exercise.