energy system

Question 1

what are the three energy systems

Answer 1

ATP–CP (anaerobic), Anaerobic Glycolysis, and Aerobic (oxidative).

Question 2

What fuels the ATP–CP system?

Answer 2

Creatine phosphate (CP).

Question 3

What fuels the anaerobic glycolysis system?

Answer 3

Glucose and glycogen (carbohydrates).

Question 4

What fuels the aerobic system?

Answer 4

Glucose, glycogen, and fats (triglycerides/free fatty acids)

Question 5

Which system resynthesises ATP at the fastest rate?

Answer 5

ATP–CP system

Question 6

Which energy system has the highest ATP yield?

Answer 6

Aerobic system (especially from fats)

Question 7

What is the rate and yield trade-off in energy systems?

Answer 7

Higher rate = lower yield; higher yield = lower rate.

Question 8

What are typical events for the ATP–CP system?

Answer 8

Maximal effort, 0–10 seconds (e.g., 100m sprint, weightlifting).

Question 9

What are typical events for anaerobic glycolysis?

Answer 9

High intensity, 10–75/90 seconds (e.g., 400m sprint, repeated efforts).

Question 10

What are typical events for the aerobic system?

Answer 10

Long duration, submaximal intensity (e.g., marathon, endurance sports).

Question 11

What is the concept of energy system interplay?

Answer 11

All systems work together but at different rates depending on intensity and duration.

Question 12

What determines ATP demand?

Answer 12

Intensity (rate of use) and duration (total yield needed).

Question 13

What’s the approximate ATP yield from 1 mole of each fuel?

Answer 13

CP: 0.7 ATP

Glucose (anaerobic): 2 ATP

Glucose (aerobic): 36–38 ATP

Fat: 100+ ATP

Question 14

Which fuel requires the most oxygen to break down?

Answer 14

Fats

Question 15

When is active or passive recovery preferred?

Answer 15

Active: Removes lactate faster (anaerobic recovery).

Passive: Replenishes CP stores (ATP–CP recovery)

Question 16

What is the ATP–CP system?

Answer 16

The energy system that rapidly resynthesises ATP using creatine phosphate (CP) without oxygen.

Question 17

What are other names for the ATP–CP system?

Answer 17

ATP–PC system, phosphate system, phosphocreatine system, phosphagen system.

Question 18

How does the ATP–CP system resynthesise ATP?

Answer 18

By breaking down CP to release energy, which joins ADP and Pi to form ATP.

Question 19

How long can the ATP–CP system sustain maximal effort?

Answer 19

Approximately 8–10 seconds

Question 20

When is the ATP–CP system the major contributor?

Answer 20

During short-duration, high-intensity activities (e.g. sprints, throws, jump

Question 21

Why does the ATP–CP system have a low yield?

Answer 21

Because CP stores in the muscle are limited and deplete rapidly.

Question 22

What happens after CP stores are depleted?

Answer 22

Other energy systems must take over as the primary suppliers of ATP.

Question 23

How long do ATP stores last at the start of exercise?

Answer 23

1–2 seconds.

Question 24

What type of recovery is best for replenishing CP stores?

Answer 24

Passive recovery.

Question 25

How much CP is restored in 30 seconds of passive recovery?

Answer 25

70%

Question 26

How much CP is restored in 3 minutes of passive recovery?

Answer 26

98%

Question 27

How much CP is restored in 10 minutes of passive recovery?

Answer 27

100%

Question 28

What is the role of EPOC in CP restoration?

Answer 28

Extra oxygen is used to recombine creatine and phosphate to restore CP.

Question 29

Example of an activity that primarily uses ATP–CP system?

Answer 29

Golf drive or 100-metre sprint.

Question 30

Why is passive recovery preferred for CP restoration?

Answer 30

Because it allows faster replenishment of CP compared to active recovery.

Question 31

What is the fuel for the anaerobic glycolysis system?

Answer 31

Muscular glycogen → glucose.

Question 32

what is the process of anaerobic glycolysis?

Answer 32

Glucose → pyruvic acid → (without oxygen) lactic acid → lactate + H⁺ + energy.

Question 33

What resynthesises ATP in anaerobic glycolysis system?

Answer 33

The energy released from breaking down glucose

Question 34

What are the by-products of anaerobic glycolysis?

Answer 34

Lactate and hydrogen ions (H⁺).

Question 35

Why is H⁺ accumulation a problem?

Answer 35

It causes fatigue by reducing muscle contraction force and speed.

Question 36

what is rate

Answer 36

how fast ATP is resynthesised. It's the speed at which the energy system produces ATP. A fast rate means ATP is made quickly to meet sudden, high demands (like sprinting). Example: Anaerobic glycolysis has a fast rate — good for short bursts of effort

Question 37

what is yield

Answer 37

How much ATP is produced It's the total amount of ATP the system can produce before it fatigues or slows down. A medium yield means it doesn't produce a lot, but more than the ATP–CP system. Example: Anaerobic glycolysis has a medium yield — more than ATP–CP but much less than the aerobic system.

Question 38

when is this system the major contributor

Answer 38

10–60 seconds of high-intensity effort, especially after CP stores deplete.

Question 39

In what types of activities is this system dominant?

Answer 39

Repeated short, high-intensity efforts, sprint finishes, hill running.

Question 40

What energy systems are used in a 400-metre sprint?

Answer 40

All three, but anaerobic glycolysis is the major contributor

Question 41

When does the anaerobic glycolysis system dominate a 400m race?

Answer 41

From ~10 to ~40 seconds, after ATP–CP stores deplete.

Question 42

. What is the aerobic system’s role in the 400m sprint?

Answer 42

Provides energy in the final ~100m (~40% contribution).

Question 43

Why does power output drop at the end of a 400m sprint?

Answer 43

The aerobic system can't resynthesise ATP as fast.

Question 44

What is active recovery?

Answer 44

Low-intensity activity (50–60% MHR) after exercise to aid recovery.

Question 45

When is active recovery most useful?

Answer 45

After anaerobic or aerobic high-intensity exercise.

Question 46

Why is active recovery better than passive after anaerobic exercise?

Answer 46

It clears H⁺ and lactate faster and maintains blood flow.

Question 47

How long should active recovery last?

Answer 47

5–10 minutes.

Question 48

What does active recovery prevent?

Answer 48

Venous pooling.

Question 49

. How does active recovery help with thermoregulation?

Answer 49

It slowly reduces core body temperature.

Question 50

What is venous pooling? .

Answer 50

Blood collects in the veins of inactive muscles, reducing blood return to the heart.

Question 51

What is EPOC?

Answer 51

Excess post-exercise oxygen consumption — the oxygen needed to recover after intense exercise.

Question 52

What is the aerobic energy system?

Answer 52

A: It resynthesises ATP using oxygen and mainly carbohydrates and fats as fuel.

Question 53

What is the rate and yield of the aerobic system?

Answer 53

Slow rate; high yield.

Question 54

What fuels can the aerobic system use?

Answer 54

Carbohydrates, fats, and (in extreme cases) proteins

Question 55

What are the three stages of aerobic metabolism of carbohydrates?

Answer 55

1. Aerobic glycolysis 2. Krebs cycle 3. Electron transport chain.

Question 56

Where do stages 2 and 3 of aerobic metabolism occur?

Answer 56

In the mitochondria.

Question 57

Which fuel produces more ATP: carbohydrates or fats?

Answer 57

A: Fats produce more ATP but require more oxygen.

Question 58

When is protein used as a fuel source?

Answer 58

A: During prolonged events like ultra-marathons (5–20% contribution).

Question 59

When is the aerobic system the dominant energy system?

Answer 59

At rest, low to moderate intensity exercise, and after ~60 seconds of continuous activity.

Question 60

What is steady state?

Answer 60

When oxygen supply meets demand and heart rate plateaus during submaximal exercise.

Question 61

What is active recovery?

Answer 61

Low-intensity movement (50–60% MHR) to help remove by-products and assist recovery.

Question 62

What does active recovery help with?

Answer 62

Increases blood flow, reduces venous pooling, lowers core temp, and removes H+ ions.

Question 63

How long does recovery take after mainly aerobic exercise?

Answer 63

Usually several minutes, depending on conditions and intensity.