Sports DrinksSports Drinks

Depletion of the body's carbohydrateDepletion of the body's carbohydratestores and dehydration are two factorsstores and dehydration are two factorsthat will limit prolonged exercise.that will limit prolonged exercise.

DehydrationDehydrationSweating is the way in which the body Sweating is the way in which the body maintains its core temperature at 37 maintains its core temperature at 37 degrees centigrade. This results in the loss degrees centigrade. This results in the loss of body fluid and electrolytes (minerals such of body fluid and electrolytes (minerals such as chloride, calcium, phosphate, magnesium, as chloride, calcium, phosphate, magnesium, sodium and potassium) and if unchecked will sodium and potassium) and if unchecked will lead to dehydration and eventually lead to dehydration and eventually circulatory collapse and heat stroke. The circulatory collapse and heat stroke. The effect of fluid loss on the body is as follows:effect of fluid loss on the body is as follows:

Physiological Effect Physiological Effect Kesan FisiologiKesan Fisiologi

% of body weight lost as sweat (% berat % of body weight lost as sweat (% berat badan menurun disebabkan peluh)badan menurun disebabkan peluh)

2% Impaired performance (2% Impaired performance (membantut prestasimembantut prestasi)) 4% Capacity for muscular work declines (4% Capacity for muscular work declines (kapasiti kapasiti

otot badan berfunsi menurunotot badan berfunsi menurun)) 5% Heat exhaustion (5% Heat exhaustion (keletihan kepanasan tubuhkeletihan kepanasan tubuh)) 7% Hallucinations (7% Hallucinations (hayalhayal)) 10% Circulatory collapse and heat stroke 10% Circulatory collapse and heat stroke

( ( edaran darah terjejas dan akan mengakibatkanedaran darah terjejas dan akan mengakibatkan

strokestroke))

ElectrolytesElectrolytes

Electrolytes serve three general functions in the Electrolytes serve three general functions in the body:body:

many are essential minerals many are essential minerals they control osmosis of water between body compartments they control osmosis of water between body compartments they help maintain the acid-base balance required for normal they help maintain the acid-base balance required for normal

cellular activities cellular activities The sweat that evaporates from the skin contains a variety of The sweat that evaporates from the skin contains a variety of

electrolytes. The electrolyte composition of sweat is variable but electrolytes. The electrolyte composition of sweat is variable but comprises of the following components: comprises of the following components:

Sodium Sodium Potassium Potassium Calcium Calcium Magnesium Magnesium Chloride Chloride Bicarbonate Bicarbonate Phosphate Phosphate Sulphat Sulphat

CarbohydrateCarbohydrate Carbohydrate is stored as glucose in the liver and Carbohydrate is stored as glucose in the liver and

musclesmuscles and is the most efficient source of energy as it and is the most efficient source of energy as it requires less oxygen to be burnt than either protein or requires less oxygen to be burnt than either protein or fat. The normal body stores of carbohydrate in a typical fat. The normal body stores of carbohydrate in a typical athlete are:athlete are:

70kg male athlete - Liver glycogen 90g and muscle 70kg male athlete - Liver glycogen 90g and muscle glycogen 400g glycogen 400g

60kg female athlete - Liver glycogen 70g and muscle 60kg female athlete - Liver glycogen 70g and muscle glycogen 300g glycogen 300g

During hard exercise, carbohydrate can be depleted at a During hard exercise, carbohydrate can be depleted at a rate of 3-4 grams per minute. If this is sustained for 2 rate of 3-4 grams per minute. If this is sustained for 2 hours or more, a very large fraction of the total body hours or more, a very large fraction of the total body carbohydrate stores will be exhausted and if not checked carbohydrate stores will be exhausted and if not checked will result in reduced performance. Recovery of the will result in reduced performance. Recovery of the muscle and liver glycogen stores after exercise will muscle and liver glycogen stores after exercise will normally require 24-48 hours for complete recovery.normally require 24-48 hours for complete recovery.

Glucose and GlicogenGlucose and Glicogen During exercise there is in an increased During exercise there is in an increased

uptake of blood glucose by the muscles uptake of blood glucose by the muscles and to prevent blood glucose levels falling, and to prevent blood glucose levels falling, the liver produces glucose from the liver the liver produces glucose from the liver stores and lactate.stores and lactate.

Consuming carbohydrate Consuming carbohydrate before, during before, during and after exerciseand after exercise will help prevent blood will help prevent blood glucose levels falling too low and also help glucose levels falling too low and also help maintain the body's glycogen stores. Many maintain the body's glycogen stores. Many athletes cannot consume food before or athletes cannot consume food before or during exercise and therefore a formulated during exercise and therefore a formulated drink that will provide carbohydrate is drink that will provide carbohydrate is required.required.

Fluid absorptionFluid absorption

There are two main factors that affect the speed at There are two main factors that affect the speed at which fluid from a drink gets into the body:which fluid from a drink gets into the body:

the speed at which it is emptied from the stomach the speed at which it is emptied from the stomach the rate at which it is absorbed through the walls of the rate at which it is absorbed through the walls of

the small intestine.the small intestine. The higher the carbohydrate levels in a drink the The higher the carbohydrate levels in a drink the

slower the rate of stomach emptying. slower the rate of stomach emptying. Isotonic drinksIsotonic drinks with a carbohydrate level of between 6 and 8% are with a carbohydrate level of between 6 and 8% are emptied from the stomach at a rate similar to water. emptied from the stomach at a rate similar to water. Electrolytes, especially Electrolytes, especially sodium and potassiumsodium and potassium, in a , in a drink will reduce urine output, enable the fluid to drink will reduce urine output, enable the fluid to empty quickly from the stomach, promote absorption empty quickly from the stomach, promote absorption from the intestine and encourage fluid retention.from the intestine and encourage fluid retention.

Sports DrinksSports Drinks

There are three types of Sports drink There are three types of Sports drink all of which contain various levels of all of which contain various levels of fluid, fluid, electrolytes and carbohydrateelectrolytes and carbohydrate..

TypeContentTypeContent Isotonic Fluid,Isotonic Fluid, electrolytes and 6-8% electrolytes and 6-8%

carbohydratecarbohydrate Hypotonic FluidsHypotonic Fluids, electrolytes and a , electrolytes and a

low level of carbohydratelow level of carbohydrate Hypertonic Hypertonic High level of High level of

carbohydratecarbohydrate

OsmolalityOsmolality The osmolality of a fluid is a measure of the number The osmolality of a fluid is a measure of the number

of particles in a solution. In a drink these particles of particles in a solution. In a drink these particles will comprise of carbohydrate, electrolytes, will comprise of carbohydrate, electrolytes, sweeteners and preservatives. In blood plasma the sweeteners and preservatives. In blood plasma the particles will comprise of sodium, proteins and particles will comprise of sodium, proteins and glucose. Blood has an osmolality of glucose. Blood has an osmolality of 280-330mOsm/kg. Drinks with an osmolality of 270-280-330mOsm/kg. Drinks with an osmolality of 270-330mOsm/kg are said to be in balance with the 330mOsm/kg are said to be in balance with the body's fluid and are called Isotonic. Hypotonic fluids body's fluid and are called Isotonic. Hypotonic fluids have fewer particles than blood and Hypertonic have have fewer particles than blood and Hypertonic have more particles than blood.more particles than blood.

Consuming fluids with a low osmolality, e.g. water, Consuming fluids with a low osmolality, e.g. water, results in a fall in the blood plasma osmolality and results in a fall in the blood plasma osmolality and reduces the drive to drink well before sufficient fluid reduces the drive to drink well before sufficient fluid has been consumed to replace losses. osmolalityhas been consumed to replace losses. osmolality

Which is most suitable?Which is most suitable?

IsotonicIsotonic - quickly replaces fluids lost by - quickly replaces fluids lost by sweating and supplies a boost of carbohydrate. sweating and supplies a boost of carbohydrate.

This drink is the choice for most athletes - This drink is the choice for most athletes - middle and long distance running or team middle and long distance running or team sports. sports.

Glucose Glucose is the body's preferred source of energy is the body's preferred source of energy therefore it may be appropriate to consume therefore it may be appropriate to consume Isotonic drinks where the carbohydrate source is Isotonic drinks where the carbohydrate source is glucose in a concentration of 6% to 8% - e.g. glucose in a concentration of 6% to 8% - e.g. 100 Plus / Glucose drink with pinch of salt.100 Plus / Glucose drink with pinch of salt.

VO2 MaxVO2 Max Fitness can be measured by the volume of oxygen you Fitness can be measured by the volume of oxygen you

can consume while exercising at your maximum can consume while exercising at your maximum capacity. VO2 max is the maximum amount of oxygen capacity. VO2 max is the maximum amount of oxygen in milliliters, one can use in one minute per kilogram of in milliliters, one can use in one minute per kilogram of body weight. body weight.

Those who are fit have higher VO2 max values and can Those who are fit have higher VO2 max values and can exercise more intensely than those who are not as well exercise more intensely than those who are not as well conditioned. Numerous studies show that you can conditioned. Numerous studies show that you can increase your VO2 max by working out at an intensity increase your VO2 max by working out at an intensity that raises your heart rate to between 65 and 85% of its that raises your heart rate to between 65 and 85% of its maximum for at least 20 minutes three to five times a maximum for at least 20 minutes three to five times a week.week.

A mean value of VO2 max for male athletes is about 3.5 A mean value of VO2 max for male athletes is about 3.5 litres/minute and for female athletes it is about 2.7 litres/minute and for female athletes it is about 2.7 litres/minute.litres/minute.