Energy Systems

what is physiology

-nutrients in food = resynthesised

-into ATP to fuel the body

Key energy nutrients

-protein

-Fats

-carbohydrates

Carbohydrates

-4 calories

-originates from fruits, vegies, grains

-carbohydrates = broken down into glucose

-glucose = stored in the liver

ATP

Adenosine Triphosphate

ATP molecule

-carbon based (carbohydrates and fats)

-universal form of energy

-muscle contraction and physiological processes

-fuel various cellular processes in the body

Resynthesize ATP

-high demand in body

-2 methods

-Anaerobic System (without oxygen)

-Aerobic System (with oxygen)

Anaerobic

-without oxygen

-occurs in the muscle

-uses present chemicals and enzymes

-short-lived physical actions

Aerobic

-with oxygen

-occurs in the mitochondria

-leads to complete breakdown of glucose

-fats and proteins = used

Metabolic pathways

-3 metabolic pathways

-Anaerobic and aerobic overlap (all activities)

-ATP-PC (Anaerobic Alactic)

-Glycolysis (Anaerobic Lactic)

-Cellular Respiration (Aerobic)

-Anaerobic Alactic

-ATP-PC

-very quick power surge

-fast and simplest pathway

-no oxygen/glucose

-10 to 15 sec duration

-important during power events

-occurs in muscle

-PC = phosphocreatine (stored in muscle and readily available)

-PC + ADP = ATP + creatine

Anaerobic Alactic Advantages

-Quick response to energy systems

-self contained (relies only on PC)

-no byproducts

-Alactic = no lactic acid

-does not involve the breakdown of glucose as an energy source

Anaerobic Alactic Disadvantages

-doesn’t last long

Anaerobic Alactic Training

-high intensity

-low frequency

-overload

-allow adequate recovery

Anaerobic Alactic Effects

-muscle hypertrophy

-Increased ATP storage

Anaerobic Lactic

-Glycolysis

-Quick longer surge of power

-breakdown of glucose

-15s to 3 min duration

-medium distance activities

-when not enough oxygen = build up lactic acid

-first step of complete breakdown of glucose

-broken down to provide ATP (11 reactions)

-glycolysis transfers energy from glucose, rejoining phosphate to ADP

-creates 2 molecules of ATP

Anaerobic Lactic Advantages

-quick response to energy systems

-self contained

-moderate capacity

-does not use oxygen

Anaerobic Lactic Disadvantages

-Lactic acid byproduct

-slow recovery (15 min - 1.5h)

Anaerobic Lactic Training

-high intensity

-overload

-adequate rest

-maintain aerobic use

Anaerobic Lactic Effects

-Increased lactic acid threshold

-increased “clearance” (moving lactate)

-increased lactic acid tolerance

-increased glycolytic enzymes

Aerobic

-cellular respiration

-long duration of power

-complete breakdown of glucose

-no lactic acid

-3 min+

-endurance sports

-occurs in mitochondria

-involves three separate pathways

• Glycolysis

• Krebs cycle

• Electron transport chain

Aerobic Advantages

-infinite duration

-mild byproducts (CO2 and O2)

-fats and proteins can be energy source

-fats = source of exercise lasing >20 min

-Protein =source of starvation (chronic)

-yields that largest ATP sum (36)

Aerobic Disadvantages

-takes time (3+ min)

-external materials required (fats, glucose, O2)

Aerobic Training

-Quantity > quality

-Increased reps

-decreased intensity

-avoid exhaustion

-diet

Aerobic Effects

-increased mitochondria

-increased energy metabolism

-increased muscle capillaries

-increased myoglycogen and VO2 Max

Glycolysis

-pyruvate = pyruvic acid (main product)

-if no oxygen stops here

-pyruvic acid = converted to lactic acid

-if oxygen then Aerobic system starts

Glycolysis + Kreb cycle

-Same as anaerobic system

-presence of oxygen = converted to Acetyl CoA instead of Lactic acid

-enters Kreb cycle (8 reactions)

-creates 2 ATP molecules

-new compounds = storing “high energy” electrons (sent to the mitochondria for ETC)

Electron Transport Chain

-final stage of cell resp

-Large amounts of ATP (34)

-CO2 and water = byproducts