Unit 9

Question 1

Define fatigue in sports.

Answer 1

A reversible, exercise-induced decline in performance.

Question 2

Outline the different types of fatigue.

Answer 2

Peripheral fatigue—develops rapidly and is caused by reduced muscle cell force
Central (or mental) fatigue—develops during prolonged exercise and is caused by impaired function of the central nervous system.”

Question 3

Distinguish between high-intensity and endurance activities.

Answer 3

High-intensity exercise →
- vigorous bout of intense activity that may last for less than a second, or as long as 1–2 minutes
- Ex. some types of interval training, plyometrics
- Sources of energy: anaerobic processes

Endurance activities →
- Prolonged sessions of low-intensity activity [minutes to hours]
- Ex. leisure cycling or jogging
- Sources of energy: aerobic processes

Question 4

Discuss causes of fatigue in different types of activity or exercise.

Answer 4

Factors: age, level of fitness and the specific type of activity

Peripheral fatigue caused by:
- Depletion of energy sources [creatine phosphate and ATP]
- Increase in levels of the products of exercise [lactate and hydrogen ions]

EX:
- Depletion of muscle and liver glycogen reserves
- Reduction in Ca2+release
- Depletion of acetylcholine
- Dehydration
- Electrolyte loss
- Overheating

Central (mental) fatigue → failure of neural transmission

Question 5

Discuss recovery from fatigue after sports.

Answer 5

Excess post-exercise oxygen consumption (EPOC) for: - Restoration of muscle creatine phosphate stores
- Removal of lactic acid
- Replenishment of myoglobin stores
- Replacement of muscle and liver glycogen stores