energy for exercise

describe the structure of ATP

it is made up of one adenosine molecule and 3 phosphate molecules which are held together by high energy bonds

describe the breakdown of ATP

• it is an exothermic reaction (releases energy)

• the enzyme ATPase acts upon the last phosphate bond of ATP, causing it to split

• the remaining elements are ADP, 2 phosphate molecules and energy

describe the resynthesis of ATP

• in order for ATP to be resynthesized, energy is required from one of the three systems (ATP-PC, Glycolytic or Aerobic system)

• this reaction is reversible and endothermic (uses energy)

explain why ATP plays a major role in the performance of a smash in Badminton (2 marks)

• it requires very high intensity exercise immediately

• this energy can come from the breakdown of ATP (using ATPase) to produce ADP, 2 phosphate molecules and energy

• the energy lasts for 3 seconds

identify the intensity, duration and an example of the ATP-PC system

intensity - very high (maximal)
duration - 2 - 10seconds

example - 100m sprint

identify the intensity, duration and an example of the glycolytic system

intensity - high

duration - 10seconds - 3 mins

example - 800m run

identify the intensity, duration and an example of the aerobic system

intensity - low-moderate (sub-maximal)

duration - 3mins +

example - marathon

describe when a footballer would use each of their energy systems

ATP-PC - when shooting, as it is high intensity and short duration

glycolytic - when playing a high press, as it is high intensity for up to 3 mins

aerobic - during half-time or when setting up a wall, as it is low to moderate intensity and can last several minutes

describe the ATP-PC system

• provides energy for very high intensity (maximal) and short duration (8-10secs) exercise

• for example, sprinting to take an interception in netball

• when ATP levels fall, ADP levels increase, resulting in the release of the enzyme creatine kinase

• this enzyme catalyses the endothermic reaction of PC into P + C + energy

• this occurs in the muscle sarcoplasm

• the energy from this breakdown is use to resynthesize ADP + P into ATP

• 1PC:1ATP

• there are no fatiguing by products from this reaction

describe the glycolytic system

• provides energy for high intensity, moderate duration (10seconds - 3mins) exercise

• glycogen is broken down into glucose by the enzyme GPP

• glucose is broken down into pyruvic acid by the enzyme PFK

• enough energy is released to resynthesize 2ATP

• in the absence of sufficient oxygen, the enzyme LDH, converts pyruvic acid into lactic acid (this all takes place in the muscle sarcoplasm)

• lactic acid decreases the PH which denatures enzymes, slowing down and eventually stopping glycolysis and ATP resynthesis

• this results in muscle fatigue and pain

• this is an anaerobic reaction

• e.g. when running 800m

name the three stages of the aerobic system

• aerobic glycolysis

• the Krebs cycle

• the electron transport chain

describe aerobic glycolysis (stage 1)

• takes place in the muscle sarcoplasm

• glycogen is broken down into glucose by the enzyme GPP

• glucose is broken down into pyruvic acid by the enzyme PFK

• enough energy is released to resynthesize 2ATP

• as oxygen is present, pyruvic acid combines with COA to produce Acetyl COA

• Acetyl COA then enters the mitochondria where stage 2 (the Krebs cycle) takes place

• this system is for low/moderate intensity, (sub-maximal) exercise with a duration of 3mins - 2hours

• e.g. when running a marathon

describe the Krebs cycle (stage 2)

• it takes place in the matrix of the mitochondria

• Acetyl COA combines with oxaloacetic acid to form citric acid which is oxidised in the Krebs cycle

• carbon dioxide is produced and removed (breathed out)

• hydrogen atoms are produced (oxidation) and removed in stage 3 (the electron transport chain)

• enough energy is produced to resynthesize 2ATP

• lastly, there is the regeneration of oxaloacetic acid