Energy for exercise

Question 1

What is ATP and how does it work? (Summarise ATP)

Answer 1

ATP is made up of one adenosine molecule and three phosphate groups held together by bonds of chemical energy.

ATP is readily available as it stored in muscle cells.

When a phosphate bond is broken down by ATPase energy is released.

This energy can be used to make muscles contract and provide movement to the body.

ATP is broken down in ADP + energy.

Question 2

Summarise ATP resynthesis

Answer 2

Depending on the intensity of exercise, resynthesis is achieved by three energy systems

Energy systems do not work in isolation

1. ATP-PC system
2. Glycolytic system
3. Aerobic system

Question 3

Summarise the ATP/PC system

Answer 3

Type of reaction - anaerobic

Chemical or food fuel used - phosphocreatine (PC)

Site of reaction - sarcoplasm

Controlling enzymes - creatine kinase

Energy yield - 1 mole of ATP

Specific stages of system - PC to P + C + ENEGRY (exothermic)
ENEGRY + ADP + P = ATP (endothermic)

By products formed - none

Question 4

Summarise the glycolytic system

Answer 4

Type of reaction - anaerobic

Chemical of food fuel used - glycogen/glucose

Site of reaction - sarcoplasm

Controlling enzymes - GPP, PFK, LDH

Energy yield - 2 moles of ATP

Specific stages of system - glucose undergoes anaerobic glycolysis
Pyruvic acid without o2 = lactic acid

By products formed - lactic acid

Question 5

Summarise the aerobic system

Answer 5

Type of reaction - aerobic

Chemical or food fuel used - glycogen/glucose or fat

Site of reaction - stage 1= sarcoplasm, stage 2 = matrix, stage 3 = cristae

Controlling enzymes = PFK and Acetyl-CoA

Energy yield - 38 moles of ATP

Specific stages of system - aerobic glycolysis, kerbs cycle, electron transport chain

By products formed - co2 and h2o

Question 6

What is the duration and intensity of each system?

Answer 6

ATP/PC = very high intensity for 2-10 seconds

Glycolytic system = high intensity for up to 3 mins

Aerobic system = low to moderate for 3 mins +

Question 7

State the strengths and weaknesses of the ATP/PC system

Answer 7

Strengths -

1. No delay for 02
2. PC readily available
3. Simple and rapid breakdown
4. Provides energy quickly
5. No fatiguing by - products

Weaknesses -

1. Low ATP yield and small PC stores lead to rapid fatigue after 8-10 seconds

Question 8

State the strengths and weaknesses of the glycolytic system

Answer 8

Strengths -

1. No delay for o2
2. Large fuel stores in liver, muscles and blood stream
3. Provides energy for high-intensity activities for up to 3 mins
4. Lactic acid can be recycled into fuel for further energy production

Weaknesses -

1. Fatiguing by-product lactic acid reduces pH and enzyme activity
2. Relatively low ATP yield and recovery can be lengthy

Question 9

State the strengths and weaknesses of the aerobic system

Answer 9

Strengths-

1. Large fuels
2. High ATP yield and long duration of energy production
3. No fatiguing by-products

Weaknesses -

1. Delay of oxygen delivery and complex series of reaction
2. Slow energy production limits activity to sub-maximal intensity

Question 10

Define the term EPOC

Answer 10

The volume of oxygen consumed post-exercise to return the body to a pre-exercise state

Question 11

State the 2 stages of EPOC

Answer 11

1. Fast (alactacid) component of recovery
2. Slow (lactacid) component of recovery

Question 12

State what happens in stage 1 of EPOC (fast alactacid component)

Answer 12

• phosphocreatine (PC) stores restored
• replenishment of blood and muscle oxygen

Question 13

State what happens in stage 2 of EPOC (slow lactacid component)

Answer 13

• elevated ventilation and circulation
• elevated body temperature
• removal of lactic acid

Question 14

State the implications of recovery on training

Answer 14

1. Warm up
2. Active recovery
3. Cooling aids
4. Intensity of training
5. Work : relief ratio
6. Strategies and tactics
7. Nutrition