Anaerobic System Fatigue and Recovery

Question 1

What is fatigue?

What factors fatigue?

Answer 1

• Fatigue refers to an inability to continue exercise at a given intensity.
• Intensity and duration.
• Type of activity.
• Type of muscle contractions utilised.
• Mental state.
• Environmental conditions.

Question 2

What are the ATP-PC system fatigue factors?

And what is the impact?

Answer 2

• Accumulation of metabolic by-products (ADP & Pi)
• Fuel depletion (CP)
• Slower muscle contractions.

Question 3

What is the anaerobic system fatigue factor?

And what is the impact?

Answer 3

• Accumulation of metabolic by-products (H+ ions)
• Muscle acidity.
• Interferes with glycolytic enzyme activity (affecting muscle contractions).

Question 4

What are the aerobic system fatigue factors?

And what is the impact?

Answer 4

(90 mins)

• Fuel depletion (Glycogen).
• Blood glucose.
• Muscle glycogen.
• Thermoregulatory fatigue.
• Dehydration.
• Slower rate.
• Greater oxygen cost.
• Lower intensity.
• Greater contribution from anaerobic system.

Question 5

ATP-PC System - Fatigue

What happens when fuel depletes in this system?

Answer 5

• Once CP depletes, energy comes from the breakdown of glucose at a slower rate.
• Therefore, force and speed of contractions also decrease.

Question 6

ATP-PC System - Fatigue

What is the disadvantage of ADP and Pi?

Answer 6

• ADP and Pi reduce the muscle contractile force.

Question 7

ATP-PC System - Fatigue

What fatigue is happening in a 50 metre freestyle?

Answer 7

Physiological changes:
- CP depletes.

Physiological impact:

• Glycogen is the predominant fuel source instead of CP.
• Slower rate.

Impact on performance:
- Becomes slower (reference data).

Question 8

Anaerobic - Fatigue

What are the stages of H+ ions in the muscles?

Answer 8

Lactic acid results from the partial breakdown of glycogen.

1. H+ ions accumulate within the working muscles.
2. The muscle cell becomes acidic (lower pH).
3. Inhibits glycolytic enzymes that catalyse (speed up) the breakdown of muscle glycogen.
4. Energy for ATP resynthesis is produced at a slower rate.
5. Muscle contractions must slow down.

Question 9

Anaerobic - Fatigue

What fatigue is happening in a 200 metre freestyle?

Answer 9

Physiological changes:
- H+ ions accumulating.

Physiological impact:

• cell acidic.
• slowed glycolytic enzymes.
• rate of energy production is slowed down.

Impact on performance:
- slower.

Question 10

What is the lactate inflection point?

Answer 10

• The lactate inflection point is the final point where lactate production and removal are balanced.
• It represents the maximum intensity athletes can still be working aerobically without any build-up of lactic acid.

Question 11

What is the fate of lactic acid?

Answer 11

• Lactate shuffles allow lactate to be moved from one location to another where it is either used as a fuel, or used to create glycogen.

Question 12

When should an athlete do a passive recovery?

Answer 12

Link to fatigue factor:
- Fuel depletion (CP)

CP is rapidly restored when recovery involves total passive rest. The rate of CP restoration depends on the recovery time.

30s = 70% CP restoration. 
60s = 75% 
120s = 95%
180s = 98%
10 mins = 100%

• An athlete should do a passive recovery when their CP fuel depletes.

Question 13

When should an athlete do an active recovery?

Answer 13

Link to fatigue factor:
- Accumulation of metabolic by-products (H+ ions).

Performing an active recovery at a low intensity speeds up the removal of H+ ions by:

• maintaining a higher blood flow (greater oxygen delivery to muscles).
• muscle pump; muscles “squeeze” surrounding blood vessels, enhancing blood flow.
• Preventing venous pooling.
• An athlete should perform an active recovery when they have depleted CP stores and H+ ions accumulate within the muscles.

Question 14

What data is extracted during the Wingate 30sec test?

Answer 14

The data is used to determine an athlete’s peak anaerobic power and anaerobic capacity.