Energy for Exercise

Question 1

define ATP

Answer 1

the only useable source of energy in the body for muscular contraction

Question 2

show the equation for the breakdown of ATP

Answer 2

ATPase

ATP ———–> ADP + phosphate + energy

Question 3

what kind of reaction is the breakdown of ATP

Answer 3

exothermic (releases energy)

Question 4

show the equation for the resynthesis of ATP

Answer 4

ADP + P + energy ——> ATP

Question 5

define coupled reaction

Answer 5

where the products of one reaction are used in another reaction

Question 6

define an exothermic reaction

Answer 6

a chemical reaction that releases energy

Question 7

define an endothermic reaction

Answer 7

a chemical reaction which absorbs energy

Question 8

write out BYEFEDS for the ATP-PC system

Answer 8

By-products = none
Yield = 1 ATP
Enzymes = creatine kinase 
Fuel = phosphocreatine 
Equations = PC (creatine kinase) -----> P + C + energy (exothermic)
                      energy + ADP + P ----> ATP (endothermic)
Duration = 2-10 seconds 
Site = sarcoplasm

Question 9

what are the advantages and disadvantages of the ATP-PC energy system

Answer 9

+ can be resynthesized quickly
+ PC stores resynthesised quickly (30 secs = 50%, 3 mins = 100%)
+ no fatiguing by-products
+ can extend duration by taking creatine supplements
+ no delay as O2 is not needed

• limited supply of PC in muscles
• only 1 mole of ATP can be resynthesised through 1 mole of PC
• PC resynthesis can only take place in the presence of O2 so intensity would have to be reduced

Question 10

show the flowchart of the anaerobic glycolytic energy system

Answer 10

Question 11

describe the advantages and disadvantages of the anaerobic glycolytic energy system

Answer 11

+ ATP resynthesises quickly as few chemical reactions
+ with sufficient O2 lactic acid converts back into glycogen in liver or into CO2 and H2O
+ used as extra burst of energy e.g. sprint finish
+ oxygen not required

• lactic acid is fatiguing
• lactic acid prevents enzymes from increasing the rate of chemical reactions
• small amount of energy can be released from glycogen under anaerobic conditions
• short duration

Question 12

show the flowchart for the aerobic energy system

Answer 12

Question 13

describe the advantages and disadvantages of the aerobic energy system

Answer 13

+ high yield of 38 ATP
+ no fatiguing by-products
+ lots of glycogen and triglyceride stores so exercise can last for a long time

• cannot be used straight away
• delay for oxygen supply to meet demand and for fatty acids and glycogen to be completely broken down
• doesn’t work at high intensities

Question 14

how does oxygen supply and fuel effect which system is used

Answer 14

O2 supply:

• if O2 is available aerobic system used
• if no O2 available then anaerobic and ATP-PC system used
• if activity is short in duration then not enough time to transport O2 to working muscles so ATP-Pc system will be used (up to 10 seconds)

fuel availability:

• pc stores = if available then use ATP-PC (cant use after 10 secs)
• glycogen = if glycogen present then anaerobic glycolytic if high intensity, if low intensity then aerobic. greater glycogen stores in muscle and liver the longer aerobic system can be used
• fats = if available then aerobic system used

Question 15

define the energy continuum

Answer 15

describes the relative contribution of each of the 3 energy systems to re-synthesise ATP according to duration and intensity

Question 16

show which energy systems represent which line of the energy continuum

Answer 16

Question 17

define intermittent exercise

Answer 17

a performer can move between any energy systems depending on the intensity and duration of the activity and fuels available

Question 18

define threshold

Answer 18

the point at which that energy system is unable to provide energy

Question 19

describe the use of recovery periods

Answer 19

• ## timeouts/ breaks between quarters/ half- times/ breaks between sets

Question 20

describe the factors that effect the contribution of energy systems

Answer 20

• position of player = goalkeeper predominantly aerobic/ midfielder anaerobic glycolytic
• tactics and strategies = man to man predominantly anaerobic glycolytic/ zonal marking more aerobic
• level of competition = high comp is anaerobic/ low comp is aerobic
• structure = field games are more aerobic due to large pitch/ court games ae higher intensity more anaerobic

Question 21

define EPOC

Answer 21

volume of O2 consumed post- exercise to return the body to its pre-exercise state

Question 22

define oxygen deficit

Answer 22

the volume of oxygen that would be required to complete the activity entirely aerobically

Question 23

draw a diagram showing how O2 consumption increases during exercise

Answer 23

Question 24

describe alactacid component of epoc

Answer 24

• replenish ATP and PC stores (4L O2 (50%= 30secs, 100%= 3 mins)
• replenish myoglobin with oxygen (1 min, 0.5L O2)

Question 25

describe the lactacid component of epoc

Answer 25

• remove lactic acid (50%=30mins, 100%-1hour)(5-8L O2)

- restore glycogen levels (consume carbohydrates)

Question 26

describe the components of lactic acid removal

Answer 26

• lactic acid is oxidised into carbon dioxide and water (65%)
• converted into glucose and then glycogen stored in muscles/ liver (25%)
• converted into protein by cori cycle in liver/ removed as sweat and urine (10%)

Question 27

explain how CO2 is removed from the body `

Answer 27

• CO2 dissolves in blood plasma which decreases blood pH this triggers chemoreceptors to stimulate CCC and RCC to elevate cardiac output and respiratory rate therefore removing CO2 via the lungs through expiration

Question 28

define OBLA

Answer 28

the point at which lactic acid begins to accumulate in the blood (4mmol.l)