Physical Education unit 3 aos 2

Food fuels

carbohydrates, fats and protein.

fatigue

the inability to sustain a required exercise intensity or the point where exercise performance begins to deteriorate.

rating of perceived exhaustion

A subjective way to measure fatigue, using a numerical rating system of 1-10

thermoregulation

refers to the ability to keep the body at optimal temperature,through functions such as sweating

dehydratioin

refers to a harmful reduction in the amount of water in the body.

electrolytes

salts in the body that control membrane stability and carry electrical charges

oxygen demand

the amount of oxygen required by the body at a given time

oxygen supply

the amount of oxygen being taken in and circulated by the body systems.

oxygen deficit

the period of time in which the bodies oxygen demand is higher than the oxygen supply from its systems.

steady state

refers to when oxygen supply is equal to oxygen demand, and the aerobic system is able to fully meet the energy requirements.

oxygen debt (EPOC)

‘Excess post-exercise oxygen consumption’. This is the amount of oxygen consumed after exercise that is higher than the amount typicaly required at resting levels.

recovery

aims to return the body to pre-exercise conditions and in doing so, reverse the effects of fatigue.

active recovery

post-event exercise that maintains at a low-moderate intensity. Keeps oxygen levels high to aid in recovery.

venous pooling

accumulation of blood in a particular part of the body

Delayed onset muscle soreness (DOMS)

the soreness felt in the days following exercise that uses muscles in ways they are not used to

passive recovery

typically involves complete rest or exercise at a very low intensity (ie. walking)

hypertonic sports drinks

drinks that contain a high proportion of sugars and electrolytes

carbohydrate loading

increasing uptake of carbohydrates in the lead up to an event

lag period

Maximal exercise

physical activity that is performed at the highest possible intensity. E.g. sprinting.

contrast water therapy

involves alternating between hot and cold water to encourage vasoconstriction and vasodilation to promote blood flow and removal of metabolic by products.

Sub-maximal exercise

physical activity that is not performed at the highest possible intensity E.g. jogging/walking.

primary food fuel used at rest

Fats

glucose

carbohydrates in the blood

glycogen

carbohydrates stored in the liver and muscles

carbohydrates

the body’s prefered source of fuel during exercise

Fats

- the bodies main source of fuel at rest and during prolonged sub-maximal exercise once glycogen stores are depleted. AKA lipids/triglycerides.

Free fatty acids (FFA’s)

fats in the blood

Adipose tissue

fat stored in the body

Oxygen demand

the amount of oxygen required by the body at any given time

Oxygen availibility

the amount of oxygen that is available to be used by the muscles at a given time

Protein

mainly used for growth and repair, but can contribute to energy when carbohydrate and fat stores have been depleted.

Amino acids

protein transported in the blood

Phosphocreatine (PC)

• a chemical fuel produced naturally within the body and stored in the muscles for use.

• Adenosine triphosphate (ATP) –

a chemical compound made up of one adenosine and three phosphates. ATP provides energy for all muscular contractions.

Adenosine diphosphate (ADP)

a chemical compound made up of one adenosine and two phosphates. ADP reforms back into ATP when it is rejoined with inorganic phosphate via the energy systems.

• How does ATP produce energy?

• ATP exist in cells all throughout the human body. Energy is released when one of the phosphates splits away, changing the molecule into ADP and inorganic phosphate.

how is ATP reformed?

• ATP is reformed/resynthesised when the bodies energy systems re-join ADP with organic phosphate.

• This cycle repeats over and over to allow a continual energy supply in the body

• There are two anaerobic energy systems. These reform ATP without the presence of oxygen. They are:

• ATP-PC system

• Anaerobic Glycolysis  system

• There is one aerobic energy system. This reforms ATP with the presence of oxygen. It is the:

Aerobic system

Pyruvic acid

molecules that are produced during glycolysis. 

how is pyruvic acid produced?

Breaking down carbohydrates into energy is known as ‘glycolysis’ and it can occur aerobically (with oxygen) or anaerobically (without oxygen). 

When either type of glycolysis occurs and energy is release, the glucose is split into two pyruvic acid molecules.

by products produced by pyruvic acid?

In aerobic conditions -  pyruvic acid transforms into non-fatiguing by-products .

In anaerobic conditions - pyruvic acid transforms into fatiguing by-products

• Aerobic glycolysis

• when glycogen is broken down using oxygen. Pyruvic acid is then converted into non-fatiguing by-products.  This process occurs when using the aerobic system.

Anaerobic glycolysis

when glycogen is broken down without using oxygen. Pyruvic acid is then converted into fatiguing by-products. This process occurs when using the anaerobic glycolysis system.

ATP-PC system  

eforms ATP via the breakdown of the chemical fuel phosphocreatine (PC) stored in the muscle. It does not require oxygen, making it an anaerobic system.

Metabolic by-products

fatiguing by-products that accumulate rapidly in the muscles when using the anaerobic systems’

The anaerobic glycolysis system

reforms ATP via the break down of carbohydrates (glycogen) without the use of oxygen.

Lactate

a substance which rapidly accumulates in the blood during anaerobic glycolysis. It does NOT cause fatigue, but it accumulates at the same rate as metabolic by-products which do.’

Hydrogen ions (H+) 

a metabolic by-product which accumulates in the muscles during anaerobic glycolysis, reducing muscle acidity and inhibiting contractions.

*NOTE – accumulation of hydrogen ions is the most significant cause of  fatigue of any of the energy systems.

Lactate inflection point (LIP)

the highest exercise intensity where lactate is being produced at the same rate as it is being removed. 

how does the Aerobic system reform ATP?

reforms ATP via the break down of food fuels using oxygen.

Aerobic lipolysis

the breakdown of fats using oxygen.

aerobic system by products