Aerobic Fatigue and Recovery

Question 1

What happens to the fuel in the aerobic system when an athlete starts to fatigue?

Answer 1

1. Muscle glycogen depletes.
2. Increased reliance on fats.
3. Fats have a greater oxygen cost, more complex process to break down.
4. Energy is produced at a slower rate.
5. Muscle contractions must slow down.

Question 2

What fatigue happens in a triathlon?

Note; swim = 18-20 mins, cycle = 64-66 mins.

Answer 2

The run begins at around the 86 minute mark.

Physiological changes:
- Glycogen depletes.

Physiological impact:
- Glycogen was preferred fuel, then fats becomes preferred fuel = slower rate of ATP..

Impact on performance:
- Athlete must slow down.

Question 3

What are the factors of thermoregulatory fatigue?

Answer 3

• Heat is a metabolic by-product of endurance activities.
• Common for body’s temp to rise when prolonged exercise and conditions of heat.

Factors:

• Elevated core body temp.
• Redistribution of blood to skin.
• Increased rate of dehydration.
• Decreased plasma levels.
• Increased blood pressure
• Electrolyte imbalance.
• Nervous fatigue.

Question 4

What happens when thermoregulatory fatigue occurs in our body?

Answer 4

1. Elevated body temp.
2. Body redistributes a higher % of cardiac output to the skin’s surface.
3. Body cools down via evaporation.

4. Increased rates of dehydration. 
Then either:
- Decreased plasma levels. 
- Increased blood pressure. 
- Nervous fatigue.

Question 5

What fatigue factors occur at particular fluid loss percentages?

Answer 5

2% = increase in core body temp.

4% = increased aerobic ability and muscular endurance.

5% = increased muscular strength and anaerobic power.

6% = muscle spasms and cramping.

8% = chance of heat stroke, excessive high core body temp.

Question 6

What happens when the body gets central nervous fatigue?

Answer 6

When fatigue is detected by the brain, weaker neural signals are sent. This will impact performance by reducing the force and speeds of contractions.

Question 7

What happens to an athlete with thermoregulatory fatigue in a long tennis match? (90 mins).

Answer 7

Physiological changes:
- increased body temp.

Physiological impacts:
- redistribute blood from muscles, fluid loss.

Impact on performance:

• increased muscle force.
• increased anaerobic contribution.

Question 8

When should athletes consume high GI carbs?

Answer 8

Link to fatigue factor:
- Fuel depletion (Glycogen).

Consumption of high GI carbs are recommended as quickly as possible during recovery to restore glycogen in the muscle. (best within 1 hour post-exercise).

Question 9

What happens to H+ when oxygen is present?

Answer 9

Converted to water (H2O).