Unit 3 Area of Study 2:How does the body produce energy?

oxygen deficit

When we first begin an activity there is a period of time where oxygen demand fromt he body exceeds the oxygen supply. This occurs because the bodies cardiovascular and respitory system take some time to increase their oxygen supply to the body at the start of physical activity

steady state

steady state occurs when the oxygen sipply is equal to the oxygendemand. This can occur after about 30 seconds when the aerobic system is providing plenty of oxygen to the workin g muscles. HEart rate will remain constant as enoufh oxygen is getting delivered to the working muscles

EPOC-excessive post exercise oxygen consumption

this is when the body is taking up transporting and consuming more oxygen than what is required as i is trying to return the body to pre-exercise state

factors associating with the amount and duration of EPOC

-how elevated or how high muscle temp is

-increased use of mitochondria

-increased atp production

-restoring PC stores

-the amount of lactate and H+ ions produced during exercise

whats vo2 max

vo2 max is the maximum amount of oxygen that can be taken up, trans[prted and used by the body in one minute for the purpose of aerobic energy production

factors affecting vo2max

body size-larger person needs more 02 than smaller person

-gender-females have smaller lung volume and left ventricle decreasing tv and sv reducing oxygen uptake

-genetics-oxygen uptake varies form 25-50% due to genetics

-age-maximal oxygen uptake declines with age

whats the training status for vo2 max

aerobic training(continuous,fartlek, and long interval) will help increase oxygen uptake as chronic adaptations will occur.

acute responses for respitory system(5)

-increased respiratory rate

-increased tidal volume

-increased ventilation

-increased pulmonary diffusion

-increased oxygen uptake

acute responses to the cardiovascular system

-increased heart rate

-increased stroke volume

-increased cardiac output(HRxSV)

-increased blood pressure

-redistributiuon of blood flow to the working muscles

-increased a-vo2diff

acuteresponses for the muscular system

-increased motor unit and muscle fibre recruitment

-increased blood flow to the muscles

-increased a-vo2diff

-increased muscle temp

-increased muscle enzyme activity

-decreased muscle substrates/fuels

heart rate

CS system

number of times the heart contracts/beats per min

Once an individual begins to exercise, their heart rate increases as a response to the extra energy required by the body. The increased heart rate increases oxygen and fuel delivery to the working musvles and aids in the removal of waste products from the muscles and body

whats your anticipatory heart rate?

the heart rate rises above resting values just before the start of exercise. Occurs because the releasr of adrenaline. Benefits inclide there beig abe to have more of a supply of oxygenated blood delivered tot he working muscles due to the increased heart rate

stroke volume

cv system

the amount of blood that leaves the left ventricle of the heart per beat. Through increased stroke volume more blood is circulated aroundthe body and more oxygen is able to be delivered by the wroking muscles

increaased cardiac output

cardiac output is the total amount of blood hat leaves the elft ventricle per minute. An increase in hr and sv will resulti n an increase in cardiac output leading to more blood being circulated around th body and more oxygen is able to be delivered to the working muscles

increased blood pressure

cv system

systolic blood pressure is the pressure is the pressure in the arteries after the blood has been pumped out of th heart and diastolic blood pressure is the pressure in the arteried when the heart fills again. Exercise results in an increase in systolic blood pressure. Exercise intenstiy increases so does the cardiac output and theefore blood pressure. arteries will vasodilate to enable greater volume of blod ot be delivered at a faster rate. Resistance training results in greater increase in bloo dpressure than endurance

blood resdistributiobn

during physical activity blood is redirected from elsewhere in the body eg the stomCH TOWARDS working muscles. This results in the working muscles receiving a higher percentage of the bodys blood that they would during rest,, which results in more oxygen beign directed tot he working muscles. DUring physicl activity blood vessels dialate which helps maintain body temperature but at mx intensity blood flow to the skin decreases and the blood is directed towards the working muscles

Increaaed respitory rate

r system

respitory rate refers to the number of breaths taken in per minute when physical activity begins, respitory rate increases resulting in more air entering our lungs resulting in more oxygen

increased tidal volume

tidal volume is the amount of air inhaled in a single breath. As physical activity begins, tiday volume increases, allowing more oxygen to be taken in to the lungs. TV plateaus at higher intesnsity meaning after this point any further increase in total ventilation is a result of an increased respitory rate

increased ventilation

ventilation is the total amount of air inhaled per minute. V=tvxrr and increase in either one of these will result in increased bentilation meaning air is able to enter the lungs where it can be diffused and transported via the blood to the working muscles

increaseds pulmonary diffusion

exercise increases the rate of exchange. PUlmonary diffusion(more diffusion at the lungs) increases and mor 02 ia siffused into the bloodstream and is delivered to the heart to be pumped to working muscles. GAsses such as oxygen and carbon dioxidealways more from areas of high concerntration to low concerntration. Upon insiration, ocygen concerntration is high so it moves from the alveoli into the blood stream to be taken to the muscles

carbon dioxide in the venou blood is high so it diffuses into the alveoli to be exhaled.

whar does increased pulmondary diffusion mean

greater amount of 02 is diffused from the alveoli to the capillaries at the lungs to be transported to the muscles to b used for aerobic energy production. It also means that greater amounts of xo2 nd waste products can be diffused from the capillaries to the alveoli to be breathed out. This enables the athlete to work at a higher intensity for longer

increaed motor unit and muscle fibre recruitment

when exercise begins, an increase in motor unit recruitment must take place, more mnuscle fibresa re activated. The nervous system increases the number of motor units recruited and the speed of motor units recruited which increases force power and strength

increased arteriovenous oxygen difference

avo2diff is the difference in concerntration of the oxygen levels between blood in the arteries compared to the blood in th eveins. Avo2 diff represents the amount of 02 extracted from the blood and consumed by muscle tissues/avodiff is larger than at rest

increaed muscle temperature

resynthesis of ATP results in increased muscle and core temperature. Metabolic activities increase core and muscle temperture-heat is a by-product of aeroic energy production. If athletes core temperature increeases, EPOC lasts for longer and takes longer to get back to pre exercise state.

increased muscle enzyme activity

oxydative enzymes-assists in metabolising triglycerides, glycogen speeding up the rate of ATP with oxygen

glycolyti enzymes-speeds up the rate that glycogen is broken down and increases speed of ATP resynthesis

ATPASE-speeds up breakdown of stored PC

creatine kinase-speeds up the breakdown of PC

increased oxygen use

the muscle cells extrct and use more oxygen from the blood because of the increased demand for ATP

decreased muscle substrates(Fuels)

all substrates/fuel storesdeplete with increeased intensirt

at max intensity the substrate that will deplete more rapidly is PC

at sub max intensity the substrate that will deplete more rapidly is glycogen

at rest the substrate that will deplete more rapidly is triglycerides intermuscular

adensoinetriphosphate(ATP)

atp is the only source of energy for muscular contractions. It consists of one adenosine moleule attached to three phosphate molecules. When one oft he phosphate molecules brreaks away, the enrgy stored in the bonds that connect molecules can be used in muscular contraction.

A small part of atp is stored in the muscles(2-3secs)after that it must be continually rebuilt from adp to atp so it can then break apart again to provide energy.

All 3 energy systems require some sort of fuel to produce atp

whata re carbohydrates broken down into

broken down into glucose and stored as glycogen

fats are broken down and stored into

stored as tryglycerides and then broken down into free fatty acids

prodominent food source during rest,sub and max intensity

rest-fats

sub max-carbohydrates contribute 2/3 to the fuel source

max-glycogen is the main food source

carbohydrates are th emain food source because they take less oxygen to produce the same amount of energy in comparison to fats

Atp-pc system

atp-pc system produces a very small amout of atp at a very fast rate. When a muscle conttracts it first uses the small amount of ATP already present in the muscle cell. As ATP levels drop,cretine phosphate in them uscles donate its phosphate group to ADP rapidly regenerating ATP.this regenerates atp for roughly 7-8 more seconds. however, pc depletes quickly and requires several minutes to full replenish