Energy systems Flashcards
Energy system interplay
All 3 ES’s work together at all times to resynthesize ATP but at different rates and level of contribution.
The role of the aerobic energy system in recovery (oxidising MB’s, resynthesing creatine).
- Forms the basis of recovery by supplying
muscles with ample oxygen to replenish
creatine stores, remove and break down
by-products (H+Ions), regulate body temp
and restore nutrient balance. - Can start this recovery as early as 30s but generally
around 1-2 mins
Understand the intensity & duration of each energy system
ATP-PC - intensity(high/very high/explosive/95% of max HR) duration(short, 1-10seconds)
Anaerobic glycolysis - intensity(high intensity/>85% of max HR) duration(intermediate duration, 10-60seconds)
Aerobic system- intensity(low/moderate/under 80% max HR) duration(long duration, 60+ seconds)
Active & Passive recovery and the advantages of both.
Active recovery anaerobic and aerobic
Consuming high GI (white bread, potato, and rice and coco-pops) within 30 minutes postgame or during because having high GI and consistent ingestion is good recovery and starts glycogen spearing and the muscles are dilated and receptive due to glycogen depletion
reduces lactic acid build-up in the muscles and it also oxidises/metabolises MB’s
Passive recovery - ATP-PC
passive recovery is a good option of recovery because it restores the PC the fastest, it replenishes 98% of the PC in 3 minutes
Understand the crossover concept in relation to fuel usage aerobically.
the crossover concept is that fat oxidation is the primary fuel at rest and during low-intensity exercise with a shift towards an increased reliance on carbohydrate oxidation at moderate to high exercise intensities. But during exercise, there is a point where the usage of fat and carbohydrates meet and crossover when the usage of both is equal
Understand the 3 mechanisms of fatigue – thermoregulatory, fuel depletion & increased
MB’s, and how/when they contribute to fatigue
thermoregulatory - aerobic system
contributes to fatigue when the core temperature changes often increase too high, above 37 degrees and cause hyperthermia and dehydration
Thermoregulatory mechanisms are increased blood flow to the skin in an attempt to increase cooling through sweat, this increase of the epidermis vasodilation reduces the amount of blood flowing to the working muscles and in a result of this, there is an decrease in O2 at the muscles which leads to an increase of h+ ions and unable for aerobic glycolysis to do its job properly therefore the athlete experiences CNS fatigue and impacts the brains ability to maintain adequate activation of muscles
fuel depletion - ATP-PC
depletion of energy fuels and substrates like ATP, CP AND glycogen that power muscular contractions
CP stores deplete rapidly and CP depletion results in ATP resynthesis reduction and therefore leads to reduction, depletion of energy or muscular fatigue. A depletion in glycogen (which varies in aerobic-based activities because of various intensities) will result in the need to use fats as a fuel source and therefore a decrease in intensity and fatigue
increased MB’s - anaerobic system
They are metabolised by-products as the result of chemical reactions within the body and are the production of energy for ATP resynthesis
Hydrogen ions are MB and once they are increased this increases muscle acidity which inhibits the action of essential glycolytic enzymes which results in a decrease in ATP resynthesis which forces a decrease in production therefore leading to fatigue
Fatigue physiology
ATP-PC - The depletion of creatine phosphate will start to get a higher contribution from the anaerobic glycolysis system which produces energy at a slower rate, therefore this will lead to a decrease in intensity
Anaerobic glycolysis - the accumulation of metabolic by-products (lactate and h+ ions) leads to an increased muscle acidity and a decrease in enzyme activity which will cause ATP resynthesis to decrease causing LIP and therefore this will lead to a decrease in intensity
aerobic system - fuel depletion of glycogen occurs after 60+mins so fat as a fuel source is utilised at a slower rate therefore this will lead to a decrease in intensity
Understand the energy system table – in particular rate & yield / Intensity & Duration
ATP-PC - rate = explosive & instantaneous (1 step), yield = extremely limited (0.7)
intensity(high/very high/explosive/95% of max HR) duration(short, 1-10seconds)
anaerobic - rate = fast (18 steps), yield = small amounts (2)
intensity(high intensity/>85% of max HR) duration(intermediate duration, 10-60seconds)
aerobic - rate = medium (120 steps) and slow (100-400 steps), yield = large amounts (36-38) and very large amounts (>100)
intensity(low/moderate/under 80% max HR) duration(long duration, 60+ seconds)
Understand the Lactate Inflection Point and be able to recognize it on a graph.
LIP is where lactate production exceeds lactate removal which is around 80% max HR
Beyond LIP, Lactate & H+Ions will continue to accumulate in the muscles
due to a lack of oxygen being present to metabolise these
MB’s. Increased H+ ions lead to increased muscle acidity. This leads to a decrease in ATP production. Therefore decreased energy is being produced. Therefore this will lead to a decreased aerobic intensity for the athlete
Why would an aerobically trained athlete have a higher LIP?
An aerobically trained athlete would have a higher LIP because they would have a greater mitochondria mass and increased capability to oxidise fat and carbohydrates at high intensities
fuel sources
ATP-PC - creatine phosphate
Anaerobic - glucose and glycogen
aerobic - glucose, glycogen, triglycerides (muscle) and free fatty acids (blood)
side notes
- the aerobic energy system is the king of recovery and is the best at metabolising by-products and replenishing the other systems
- once the aerobic system is the major contributor, it will remain so
- Rate: How quickly ATP is Resynthesised
- Yield: The total amount of ATP that is resynthesised during an exercise
bout. - ATP Demand: How much ATP is required during an activity and the
the rate at which it is expended and resynthesised - ATP-PC examples is jumping, kicking and short sprints, and 100m track sprint
An anaerobic example is repeated sprint efforts, 400m track sprint and 100m freestyle race
an aerobic example is a 10,000m run and 40km cycle track
