Causes of Fatigue Flashcards
What are the three acceptable causes of fatigue?
- Depletion of Fuel
- Accumulation of metabolic by-products
- Elevated Core Body Temperature
Which two fuels are reffered to for depletion of fuels?
- PC Stores
- Glycogen Stores
After how long do PC stores deplete, and which system does it affect?
After approximately 10 seconds of high intensity exercise. Affects ATP-PC energy system.
After how long do Glycogen stores deplete, and which system does it affect?
After approximately 90 minutes of high intensity activity.
Which energy system does glycogen depletion affect.
Aerobic Glycolysis Energy System
After glycogen depletion, aerobic energy system relies on which fuel for energy?
Triglycerides
Why does an athlete’s intensity drop when they hit the wall?
- They deplete their glycogen stores, and rely on their triglyceride stores
- Triglycerides require more oxygen for breakdown
- Triglyceride breakdown is a complex reaction
- Therefore, rate of ATP synthesis is slower, leading to decrease in intensity.
What is an important metabolic bi-product?
Accumulation of Hydrogen Ions
What system causes accumulation of Hydrogen Ions?
Anaerobic Glycolysis System
What does accumulation of Hydrogen Ions cause?
- Decrease in muscle pH levels
- Increase in muscle acidosis
- Inhibits enzyme activity
- Decreases rate of ATP resynthesis, results in lower intensity
What is a by-product of the Aerobic ATP resynthesis?
Heat Energy
What is the body’s core body temperature?
37 degrees C
What is the name of the process when body regulates rise in core body temperature?
Thermoregulation
What is Vasodilation and Vasoconstriction?
- Vasodilation - Expansion of blood vessels
- Vasoconstriction - Constriction of blood vessels
What is Stroke Volume?
The amount of blood the heart can pump out in a single beat
What is blood viscosity?
The thickening of blood and it’s resistance to flowing.
Explain in simple dot-points the steps involved in thermoregulation
- Redistribution of blood flow
- Sweating
- Reduction in stroke volume due to viscosity
Each dot-point will have it’s own flashacrd later
Explain the redistribution of blood flow in body in terms of Elevated Core Body Temperature
- Blood is redistributed away from muscles and to the skin
- Blood vessels vasoconstrict to muscles and vasoldilate to skin
- Means less blood going to muscles will result in less oxygen, leading to lower intensity
Explain sweating in terms of Elevated Core Body Temperature
- Blood taken to skin’s surface will cause sweating
- Sweat will be produced mainly by water from blood plasma
- Decrease in water levels in blood will increase viscosity
- Evaporation of sweat on skin will enable cooling
Explain reduction of stroke volume due to blood viscosity in terms of Elevated Core Body Temperature
- Due to increased viscosity of blood, it is harder for heart to pump blood
- Therefore stroke volume will lower
- This will result in less blood being pumped = less oxygen reaching muscles = lowering intensity
What does multifactorial causes of fatigue mean?
Many causes of fatigue
