Hydration Flashcards
What are the three main things sports drinks contain?
Carbohydrates, electrolytes and flavour
What is the purpose of carbohydrates in sports drinks?
To provide a fuel source for the muscles and brain, as well as contributing to the flavour of the drink
What happens when carbohydrate concentration is below 8%?
Both carbohydrate and water are rapidly absorbed from the small intestine
What happens as carbohydrate concentration increases beyond 8%?
Water absorption slows
What do sports drinks use as carbohydrate sources?
Glucose, glucose polymers, sucrose and fructose
What is the total carbohydrate concentration in sports drinks?
4-8g per 100mL
What does replacing glucose with glucose polymers help?
To improve the rate at which carbohydrates and fluids empty from the stomach
Which key electrolytes do sports drinks contain?
Potassium and sodium
What is the purpose of sodium in sports drinks?
To stimulate the absorption of carbohydrates and water from the small intestine, and encouraging you to drink more and replace fluids faster
How many mmol/L of sodium are in most sports drinks?
10-25 mmol/L of sodium
What do higher levels of sodium encourage?
Better fluid retention during rehydration
What is the issue with higher levels of sodium?
The higher the levels of sodium, the less palatable the drink is
Why is flavour an important feature of a sports drink?
The more you enjoy the flavour, the more you will drink
How much of their fluid losses do most athletes replace during exercise?
Only half their fluid losses and fail to fully rehydrate
When has carbohydrate intake during exercise been shown to enhance performance?
Over 90 minutes of lower intensity exercise, prolonged periods of high-intensity exercise of over 60 minutes, high-intensity exercise and athletes who have heavy sweat losses
What type of sports are sports drinks best suited for?
Endurance and high-intensity sports
What are the three types of commercial sports drinks?
Hypotonic, isotonic and hypertonic
Describe hypotonic drinks in relation to the body’s fluids and carbohydrates?
They are less concentrated then the body’s fluids, contain little to no carbohydrates and will be absorbed at the fastest rate
What do hypotonic drinks help with?
Rapid re-hydration during or immediately after long exercise sessions
Describe isotonic drinks in relation to the body’s fluids and carbohydrates?
They have similar concentration to the body’s fluids, contain some carbohydrates and electrolytes and are absorbed quickly
What are isotonic drinks ideal for?
Re-hydration and topping up glycogen stores during or following exercise
Describe hypertonic drinks in relation to the body’s fluids and carbohydrates?
They are more concentrated than body fluids and are absorbed slowly
What are hypertonic drinks not ideal for?
Re-hydration because of their high carbohydrate content
What are hypertonic drinks suitable for?
Replenishing fuel stores to aid recovery and should be taken with isotonic or hypotonic drinks
What does sports water contain and what is it suitable for?
A lower carbohydrate and electrolyte content, suitable for moderate exercise of less than an hour
What is the issue with cordials, soft drinks and juices?
They are too high in carbohydrates and too low in electrolytes for ideal fluid replacement
What does carbonation in soft drink do?
Decreases voluntary fluid intake
What is the absorption of water like and what is it suitable for?
Water is absorbed as quickly as sports drinks and is suitable for low intensity or short duration exercise
What is the problem with energy drinks?
Carbohydrate concentration is generally too high in energy drinks
