energy systems
DESCRIPTION
Energy Systems. Energy Systems for Exercise. Energy Systems. Immediate energy ATP-PC Short-term energy Lactic acid system Long-term energy Aerobic system. ATP-PCr System. ultra-short duration (< 6 seconds) high intensity require an immediate and rapid supply of energy 100-m sprint - PowerPoint PPT PresentationTRANSCRIPT
Energy Systems
Energy Systems for Exercise
Energy Systems Energy Systems
Immediate energy ATP-PC
Short-term energy Lactic acid system
Long-term energy Aerobic system
ATP-PCr System ATP-PCr System
ultra-short duration (< 6 seconds)
high intensity require an immediate and
rapid supply of energy 100-m sprint 25-m swim Smashing a tennis serve Thrusting a heavy weight
upwards
Lactic Acid SystemLactic Acid System
During performances of short duration and high intensity that require rapid energy transfer that exceeds that supplied by phosphagens 400-m sprint 100-m swim Multi-sprint sports
Anything up to 3 minutes Lactate is the by product “Lactic acid system’
Lactate Shuttling
Pyruvate Acetyl CoA
Citric acid cycle Oxidation =
removal + energy
Lactic Acid System Lactic Acid System
Blood lactate removal Gluconeogenesis-
conversion to glucose through Cori cycle in the liver
Oxidation to pyruvate Fuels citric acid cycle
Lactate Threshold
The exercise intensity prior to the abrupt increase in blood lactate A.k.a onset of blood
lactate accumulation (OBLA)
Lactate / Lactic AcidLactate / Lactic Acid
Terms: LACTATE AND LACTIC ACID Lactate production and accumulation in
muscle coincides with, rather than causing acidosis
DOMS incorrectly attributed to lactate build-up
Caused by damage to muscles not the pain from damaged muscle cells, but from
the reinforcement process- adding new sarcomeres (the segments in the muscle fibrils)
reinforcement process causes the cells to swell and put pressure on nerves and arteries, causing DOMS.
Aerobic Energy SystemAerobic Energy System
Duration > 2/3 minutes Lipids
Lipolysis Beta oxidation Kreb’s cycle
Carbs Glycolysis Pyruvate Acetyl CoA Krebs cycle (citric acid cycle or tricarboxylic acid cycle) Electron transport chain
Energy requirements at rest
Almost 100% energy comes from aerobic metabolism
Therefore blood lactate levels are steady and low (<1.0 millimoles p/L)
7- kg young adult consumes 0.25 L O2 p/min
Transition to Exercise
O2 consumption
Recovery
O2 consumption remains elevated
O2 Dept = payment for O2 deficit
Vo2 Max
Determines cardiovascular fitness
O2 uptake increases with intensity of exercise up until a certain point
ml/kg/minute Factors influencing:
Delivery uptake
Muscle Fibre Types
Type 1 = Slow twitch Generates energy aerobically For endurance exercise
Type 2 = fast twitch 2a- some aerobic power = anaerobic 2b-predominantly anaerobic
Generates energy anaerobically For short intense exercise
Implications
Recovery from exercise
Remove lactate Re-oxygenation muscle myoglobin Replace
Muscle glycogen PCr Lipid levels
Active recovery
Movement at a lower intensity/ submax performed immediately after exercise
Assists with oxidation of lactate (Lactate shuttling)
But may impair
glycogen synthesis
Passive recovery
Lie down complete inactivity
Theory is that this ‘frees’ oxygen for the recovery process
Which is best?
Research inconclusive Depends on exercise to recover from Steady rate exercise
PCr stores not depleted Lactate levels not increased Depends on post exercise glucose intake
Intense/Non-Steady rate exercise Large O2 deficit
Lactate Removal
Exercise Recovery
Passive
Active Passive
Training the Energy Systems
Training the ATP-PC system
4 to 7 seconds of high intensity work at near peak velocity are required e.g. 3 × 10 × 30 metres with recovery of 30
seconds/repetition and 5 minutes/set. 15 × 60 metres with 60 seconds recovery 20 × 20 metres shuttle runs with 45
seconds recovery
Training the anaerobic lactate system
5 to 8 × 300 metres fast - 45 seconds recovery - until pace significantly slows
150 metre intervals at 400 metre pace - 20 seconds recovery - until pace significantly slows
8 × 300 metres - 3 minutes recovery (lactate recovery training)
Training aerobic systems
4 to 6 × 2 to 5 minute runs - 2 to 5 minutes recovery
20 × 200m - 30 seconds recovery 10 × 400m - 60 to 90 seconds
recovery 5 to 10 kilometre runs
Chronic Adaptations to Training
Metabolic pathway Adaptation Consequence
Mitochondrialrespiration
Small May improve recovery
Glycogen Concentration Fuel for glycolysis
Glycolysis Activity ofphosphorylase
Rate of glycolysis
Activity of PFK Rate of glycolysis
ATP Small Tolerance of intenseexercise
Metabolic pathway Adaptation Consequence
Creatinephosphate
Small Capacity to rapidlyregenerate ATP
Buffering capacity Capacity Delays fatigue fromacidosis ATP from glycolysis
Summary
Immediate energyATP-PC Short-term energy Lactic acid system Long-term energy Aerobic system Dynamic balance Training Recovery