Homeostasis:
Definition- maintaining stable conditions in the body. (“resting condition”)
Examples of Homeostasis: Body Temperature and Blood Sugar.
Steady State- balance between demands on body and physiological response. (“exercise”)
- Constant/ not necessarily normal
- Maintaining a pace while running.
Biological Control System: (3 Parts)-
1. Sensors and receptors- Detects changes in variables. (tells control center to increase or
decrease).
2. Control Center- Initiates a response (+/-)
- Positive Feedback- initial response increases original stimulus. (Birth)
- Negative Feedback- most control centers utilize. Reverses original stimulus in
homeostasis.
3. Effector- Changes internal environment back to normal.
The effects of exercise on homeostatic control:
- Exercise disrupts homeostasis. (decreases PH)(increases PO2 & PCO2).
Adaptation: changes in structure and function of a cell or organ system.
- Improves ability to maintain homeostasis.
Acclimation: adaptation to environmental stresses.
- Only works when adaptation occurs
- Improves function of the homeostatic system that already exists.
Hormesis: process in which a low dose of harmful stress benefits an adaptive response on the cell
or organ system.
Bioenergetics:
Definition- How humans make energy in the body.
3 macronutrients:
1. Carbohydrates(easiest way to make ATP)
2. Lipids
3. Proteins
Metabolism- how fast we break down food.
Lipolysis- Breakdown of triglycerides into glycerol and fatty acids.
Beta- Oxidation- Triglycerides---->FFA----->ACETYL COA
Coupled reaction: Energy in an exergonic reaction drives an endergonic reaction.
Enzymes: Catalysts that regulate speed of reactions.
- 2 factors that regulate enzyme activity- Temperature & PH
- Lower activation energy required.
- Activation energy = energy required to initiate chemical reactions.
, 2 Ways to make ATP:
1. Anaerobic Pathway- (No O2) Outside of mitochondria: ATP-PCR; Glycolysis
2. Aerobic Pathway- (requires O2) Inside of mitochondria: Krebs; ETC (makes a lot more
ATP.)
ATP-PC: Glycolysis:
- Sarcoplasm - Sarcoplasm
- Anaerobic - Anaerobic
- 0-15 seconds - 15 Sec- 3 mins
- Creatine Kinase - Phosphofructokinase
- Powerlifting, 1-RM - Basketball; Hockey
- ADP+PC----->ATP+C - 2 Phases: Investment & Generation
Krebs Cycle: ETC:
- Mitochondrial Matrix - Mitochondrial Membrane
- Aerobic - Aerobic
- 3-4 Mins - Greater than 3-4mins
- Isocitrate Dehydrogenase - Cytochrome Oxidase
- 5k-10k
Energy to perform exercise comes from the reaction between anaerobic and aerobic metabolism.
- Anaerobic: Short-term; high intensity
- Aerobic: Long-term; low intensity
Exercise Metabolism:
Energy Requirements at rest-
- Blood Lactate levels are low. (<1.0mmol/L)
- 0.25 L/min (absolute) “How many you are consuming”
- 3.5 ml/kg/min (relative) “weight” MORE ACCURATE!
Rest to Exercise Transition-
- ATP production increases
- Uptake of O2 increases greatly. (reaches steady state in 1-4 mins).
- When steady state is reached, ATP is taken over via oxidative phosphorylation.
Oxygen Deficit- Lag in oxygen uptake at beginning of exercise.
- Trained adults and adolescents reach SS VO2 faster than untrained.
During recovery from exercise; O2 uptake remains elevated above rest levels.
Oxygen Debt- repayment for O2 deficit at onset of exercise.
- 2 Phases:
1. Rapid Portion- resynthesis of stored PC, replenish muscle and blood O2 stores.
2. Slow Portion-
- Elevation of Heart Rate and Breathing(increases energy need)
- Elevation of body temp (increases metabolic rate)
- Elevation of Epinephrine and Norepinephrine
- Lactic acid turns to glucose
Definition- maintaining stable conditions in the body. (“resting condition”)
Examples of Homeostasis: Body Temperature and Blood Sugar.
Steady State- balance between demands on body and physiological response. (“exercise”)
- Constant/ not necessarily normal
- Maintaining a pace while running.
Biological Control System: (3 Parts)-
1. Sensors and receptors- Detects changes in variables. (tells control center to increase or
decrease).
2. Control Center- Initiates a response (+/-)
- Positive Feedback- initial response increases original stimulus. (Birth)
- Negative Feedback- most control centers utilize. Reverses original stimulus in
homeostasis.
3. Effector- Changes internal environment back to normal.
The effects of exercise on homeostatic control:
- Exercise disrupts homeostasis. (decreases PH)(increases PO2 & PCO2).
Adaptation: changes in structure and function of a cell or organ system.
- Improves ability to maintain homeostasis.
Acclimation: adaptation to environmental stresses.
- Only works when adaptation occurs
- Improves function of the homeostatic system that already exists.
Hormesis: process in which a low dose of harmful stress benefits an adaptive response on the cell
or organ system.
Bioenergetics:
Definition- How humans make energy in the body.
3 macronutrients:
1. Carbohydrates(easiest way to make ATP)
2. Lipids
3. Proteins
Metabolism- how fast we break down food.
Lipolysis- Breakdown of triglycerides into glycerol and fatty acids.
Beta- Oxidation- Triglycerides---->FFA----->ACETYL COA
Coupled reaction: Energy in an exergonic reaction drives an endergonic reaction.
Enzymes: Catalysts that regulate speed of reactions.
- 2 factors that regulate enzyme activity- Temperature & PH
- Lower activation energy required.
- Activation energy = energy required to initiate chemical reactions.
, 2 Ways to make ATP:
1. Anaerobic Pathway- (No O2) Outside of mitochondria: ATP-PCR; Glycolysis
2. Aerobic Pathway- (requires O2) Inside of mitochondria: Krebs; ETC (makes a lot more
ATP.)
ATP-PC: Glycolysis:
- Sarcoplasm - Sarcoplasm
- Anaerobic - Anaerobic
- 0-15 seconds - 15 Sec- 3 mins
- Creatine Kinase - Phosphofructokinase
- Powerlifting, 1-RM - Basketball; Hockey
- ADP+PC----->ATP+C - 2 Phases: Investment & Generation
Krebs Cycle: ETC:
- Mitochondrial Matrix - Mitochondrial Membrane
- Aerobic - Aerobic
- 3-4 Mins - Greater than 3-4mins
- Isocitrate Dehydrogenase - Cytochrome Oxidase
- 5k-10k
Energy to perform exercise comes from the reaction between anaerobic and aerobic metabolism.
- Anaerobic: Short-term; high intensity
- Aerobic: Long-term; low intensity
Exercise Metabolism:
Energy Requirements at rest-
- Blood Lactate levels are low. (<1.0mmol/L)
- 0.25 L/min (absolute) “How many you are consuming”
- 3.5 ml/kg/min (relative) “weight” MORE ACCURATE!
Rest to Exercise Transition-
- ATP production increases
- Uptake of O2 increases greatly. (reaches steady state in 1-4 mins).
- When steady state is reached, ATP is taken over via oxidative phosphorylation.
Oxygen Deficit- Lag in oxygen uptake at beginning of exercise.
- Trained adults and adolescents reach SS VO2 faster than untrained.
During recovery from exercise; O2 uptake remains elevated above rest levels.
Oxygen Debt- repayment for O2 deficit at onset of exercise.
- 2 Phases:
1. Rapid Portion- resynthesis of stored PC, replenish muscle and blood O2 stores.
2. Slow Portion-
- Elevation of Heart Rate and Breathing(increases energy need)
- Elevation of body temp (increases metabolic rate)
- Elevation of Epinephrine and Norepinephrine
- Lactic acid turns to glucose
