Water Flashcards
How much of our body is composed of water?
50-60%
Why is water important?
- Regulates body temperature
- Removes waste-lactic acid (Slow stage EPOC)
- Transports nutrients, glucose, and oxygen via blood plasma
- Moistens the air passages for expiration
Why is water important during exercise? (9 point slide)
- Exercise=exothermic=heat +energy
- Sweating occurs to prevent overheating
- Loss of water causes a drop in blood volume
- Blood viscosity increases
- Venous return decreases
- Stroke volume decreases
- Heart rate increases
- Blood flow to skin is reduced (vasoconstriction) to prevent further sweating (water loss)
- Core body temp increases, leading to fatigue/heat exhaustion.
How does the loss of fluid affect performance?
- Decreasing aerobic performance
- Decreased reaction time -> loss of electrolytes
- Decreased concentration
- Decreased decision making
- Heat stroke
What are electrolytes?
Salts and minerals found in the blood plasma
What is the function of electrolytes?
- Vital for proper functioning of cells
- Key for electrical transmission of nerve impulses that control muscle contraction (all or none law, spatial summation, motor units etc)
What are the 3 most important electrolytes?
- Sodium
- Calcium
- Iron
How are electrolytes lost?
Through sweating
What does the loss of electrolytes lead to?
- Muscle weakness
- Muscle cramps
- Impaired decision making and drowsiness
- Abnormal heart rhythm due to cardiac interference
Why does drinking plain water stimulate more water loss, affecting sodium levels?
As plain water does not contain electrolytes or carbohydrates, providing no energy supply or electrolytic balance
How much water should be drank prior to an event?
- 400-600ml of fluid 2 hours before
- 200-300ml of fluid 15 mins before
- Meal or snack high in carbs 2-4 hours before
What should you drink during an event?
Powerade or lucozade sport little and often! As they contain glucose and electrolytes
What/when should you drink following an event?
- Rehydrate immediately!
- Electrolyte drink
- Eat a carbohydrate meal 2 hours after play as it opens up a carbowindow; restore glycogen levels in slow stage of EPOC