Hormone Regulation of Exercise Flashcards
Adrenal Medulla (Kidney)
Catecholamines
NE & EP
Increases HR, BP, Respiratory Rate
Increases Metabolic Rate, glycogenolysis; Release of FFA and glucose into blood
Aldosterone
Released by Adrenal Gland - Cortex in response to low BP or blood flow
Promotes sodium retention in kidneys and plasma volume
Antidiuretic hormone (ADH)
Released by Posterior Pituitary in response to low blood osmolarity
Promotes water conservation by plasma volume
Renin-angiotensin Mechanism
Sweat->Decreased blood flow to kidney->kidney creates renin->converts to angiotensin 1 -> converts to angiotensin II when converting enzyme is present (Na+ and Water Reabsorbed)
What does an ACE inhibitor do?
Stops Angiotensin II from being made by stopping the enzyme from working
Lower BP
Hormones Increasing Fat Metabolism
Cortisol (Stress) from adrenal cortex
Epinephrine
Norepinephrine
GH from anterior pituitary
*When CHO is low hormones accelerate fat breakdown to provide muscles with energy
Hormones from Pancreas and function
Insulin - released when hyperglycemic (plasma glucose high)
Glucagon - released when hypoglycemic
Plasma levels of glucose and insulin-exercise (Graph)
Receptors are more sensitive to insulin when exercising. More sensitive so we need less insulin.
Glucose Transporters
Glut 1 and Glut 4
Glut 1 is on sarcolemma, produces some glucose
Glut 4 is in cell muscle membrane, produces a lot of glucose. Alpha a subunit insulin receptor
Autophosphorylation of tryosin residues on the alpha a subunit
Nore and Epi act on alpha receptors, cause constriction.
What is special about the Glut 4 receptor?
Insulin or exercise can stimulate glucose release. Those with high glucose levels should use exercise as a natural remedy.
Diabetes
Metabolic Disease that affects bodies ability to use glucose; Systemic disorder
Hyperglycemia (defects in)
-insulin secretion
-Insulin action
Type 1 - complete insulin deficiency
Type 2 - (90-95%) resistance to insulin; impairment to secretion of insulin; excess glucose production by liver
Diabetes Risk Factors
Non-Modifiable: Age, Race, Family Hx
Modifiable: Obesity, hypertension, inactivity, Polycystic Ovary Syndrome, gestational diabetes
Diabetes - Diagnostic Criteria
Any positive on 2 occasions:
1. Hemoglobin A1C: Greater than or equal to 6.5%
2. Sx and causal plasma glucose: Greater than 200 mg
3. Fasting Plasma Glucose: Greater than or equal to 126 mg
4. Oral Glucose Tolerance Test: Greater than 200 mg
-Drink 75 mg of glucose in water
-2 hours after drink measure
Pre-Diabetes - Diagnosis
Impaired Oral Glucose Test: 140 to 199 mg after 2 hours after drink
Impaired Fasting Glucose: Greater than 100 mg and less than 126 mg
A1C: 5.7-6.4%
What is insulin resistance?
Associated with Pre-Diabetes Type 2
Disorder in which target tissues fail to use insulin effectively (muscles, fat and liver)
What happens during the onset of insulin resistance?
Pancreas compensates and creates more insulin
-Body has high levels of plasma glucose and insulin
Gradually capacity to create insulin fails
Timing of insulin secretion is abnormal
Screening for Diabetes
Testing for Type 2 in asymptomatic persons:
-Overweight or obese and have 1 or more RF
-Physical inactivity
-1 degree family member with diabetes
RF:
High risk race
Women with baby greater than 9 pounds or gestational D
HTN
HDL less than 35
Triglycerides greater than 250
A1C greater than 5.7%
Hx of CVD
Hypoglycemia
Too low glucose available
Most common problem
Too much insulin present
Accelerated absorption at injection site
Can occur during Ex or 4-6 hours after
Symptoms of Hypoglycemia
Sweating
Anxious
Irritable
Hunger
Dizziness
Impaired Vision
Weakness, Fatigue
Headache
Tx of Symptomatic Hypoglycemia
Less than 70 mg/dl
If symptomatic
-Ingest 15 g CHO, recheck after 15 min
-If still give additional 15 g CHO
Ex: 4 oz fruit juice
Pre-Ex Hypoglycemia (Not Symptomatic)
Glucose: Less than or equal to 100
If taking insulin or oral agent (Ex:Metforamen)
-Giver 15 g CHO w/ fat/protein
If not taking I or O,
-No need for snack, low risk
If they have a pump, self management
Post-Ex Hypoglycemia (Not Symptomatic)
Goal is to have glucose equal or above 100 mg/dl
If less and using Insulin or oral agent
-Give 15 g CHO w/ fat/protein
-If continues medical consult
Signs of Hyprglycemia
Hunger
Nausea
Excessive Thirst
Frequent Urination
Excessive Dry Skin
Drowsiness
Impaired/Blurred Vision
HI FED NE
Pre-Ex Hyperglycemia
Greater than or equal to 300mg/dl
Acute setting Type 2:
-Can exercise with caution if feeling well and hydrates
-Do not need ketones tested unless prescribed
Type 1
-Can exercise greater than 300 if no ketosis (blood or urine)
Ketone (byproduct of fat)
Fatigue and Causes
PCr depletion after 14 seconds
Glycogen depletion around 30 minutes
Accumulation of lactate and H+
-Decreases muscle pH, impairs energy production and muscle contraction
May serve as a protective mechansim
Metabolic By-Product and Fatigue
Cells buffer H+ with biarbonate around 6.4 to 7.1
pH lower than 6.9 slows glycolysis and energy production
pH reaches 6.4, stops glycolysis and results in exhaustion
Basal Metabolic Rate (BMR)
Minimum required energy for essential physiological function
~1,200-2,400 kcal/24 hr
Factors affecting BMR
Fat Free Mass
Body Surface Area
Age
Body Temperature
Stress
Thyroxine and epinephrine
